Useful Properties of
er
ac
es
es
ROBE ROBERT RT KERN KERN Hoff Hoffma mann nn La Roch Roch Inc. Inc.
It is im orta orta
to reco recogn gniz izee-th that at
ipin ipin
ofte ofte acco accoun unts ts
mini minimu mu numb number er ofst ofstep eps. s. ro id ba ic esig esig info info mati mation on an es enti ential al data data equi equipm pmen en in hydr hydrau auli li syst system ems. s. Expl Explai ain, n, as requ requir ired ed th un amen amenta ta rela relati tion on hips hips uler uler er oull oull an Da cy to appl applie ie hydr hydrau auli lics cs Furt Furthe herm rmor ore, e, spec specif ific ic refe refere renc nces es \Vil \VilIb Ib made made to desi design gn data data if no show show with within in thes thesea eart rtic icle les. s.Th Thes ese~ e~rt rtic icle les, s, th acco accomp mpan anyi ying ng data data an l'e, l'e,fe fere renc nces es will engi engine neer er ju no ente enteri ring ng this this fiel fiel el to thos thos np th this this firs firs inst instal allm lmen ent. t. Th this this seri series es
nl
ewto ewto ia
defi defini niti tion ons, s, nome nomenc ncla latu ture re luid luid
il
co si ered ered
Dens Densit itie ies: s: Liqu Liquid id
expr expres esse se in lh/f lh/ft" t" [5a]. Fo exam exampl ple, e, th dens densit it of wate wate is P 6 0 w 62.37 62.37 Ib/ft Ib/ft at 60°F 60°F Pres Pressu sure re ha no prac practi tica ca effe effect ct on liqu liquid id dens densit ity. y. HowHowever ever incr increa easi sing ng temp temper erat atur ures es will will caus caus liqu liquid id to expa expand nd lo .\ :te io in th temp temper erat atur ur chan change ge in pipe pipe syst system em This This expa expans nsio io acto acto is P 6 P , where te pera peratu ture re ence ence th olum olum lo rate rate tu where is volu volume me flow flowra rate te at 60°F 60°F 58
DECEMBER
1974/C /CHE HEMI MICA CA 23, 1974
ENGI ENGINE NEER ERIN ING> G>
Pipi Piping ng-d -des esig ig te
calc calcul ulat atio ions ns sh ul io lt
made made at flow flowin in ti
Specif Specific ic volume volume ft3jlb. ty
ec
al
=:
ljp,
la
at
c, and
at (1)
P601/P60W
S60
en in
th
al lu in redu reduce ce pres pressu sure re an redu reduce ce temp temper erat atur ure. e. Example ar ia an ro Tabl Tabl we find find that that th crit critic ical al pres pressu sure re
iv P/P60to
where If if
is th dens densit it
en itie ities: s: Vapo Vapo
of liqu liquid id at flow flowin in temp temper erat atur ure. e.
an
Ga
PV =: RTz, where is abso absolu lute te ress ressur ure, e, lb/f lb/ft' t''; '; spec specif ific ic volu volume, me, ft lIb; lIb; univ univer ersa sa ga cons consta tant nt (ft) (ft)(l (lb) b)j( j(lb lbXO XOR) R) an =: I) Sinc 1,544jM, wher ga (u uall uall Sinc wher th mole molecu cula la weig weight ht =: 144P', where P' lute lute pres pres ure, ure, psia psia an lI la be ewri ewritt tten en as
Tz
density,
p,
1O.72Tz
rt
.e
is
(3)
1,544T/M
as: ---, ---,
l.
is
(4)
lb/ft"
AsEq. (4 show show ga dens densit itie ie depe depend nd on pres pres ur an temp temper erat at re Henc Hence, e, fo purp purpos oses es of calc calcul ulat atio io pipe pipe in te es ly this this cula cula iz
Spec Specif ific ic volu volume me is th reci reci roca roca of ensi ensity ty ft /Ib. /Ib. high high temp temper erat atur ures es an pres pressu sure re ga es do no foll follow ow cl sely sely th idea idea as law, law, an :j:. 1. Th nume numeri ri CHEMIC CHEMICAL AL
ENGINE ENGINEERI ERING/ NG/DEC DECEMB EMBER ER
23, 1974
59
Pipi Piping ng-d -des esig ig te
calc calcul ulat atio ions ns sh ul io lt
made made at flow flowin in ti
Specif Specific ic volume volume ft3jlb. ty
ec
al
=:
ljp,
la
at
c, and
at (1)
P601/P60W
S60
en in
th
al lu in redu reduce ce pres pressu sure re an redu reduce ce temp temper erat atur ure. e. Example ar ia an ro Tabl Tabl we find find that that th crit critic ical al pres pressu sure re
iv P/P60to
where If if
is th dens densit it
en itie ities: s: Vapo Vapo
of liqu liquid id at flow flowin in temp temper erat atur ure. e.
an
Ga
PV =: RTz, where is abso absolu lute te ress ressur ure, e, lb/f lb/ft' t''; '; spec specif ific ic volu volume, me, ft lIb; lIb; univ univer ersa sa ga cons consta tant nt (ft) (ft)(l (lb) b)j( j(lb lbXO XOR) R) an =: I) Sinc 1,544jM, wher ga (u uall uall Sinc wher th mole molecu cula la weig weight ht =: 144P', where P' lute lute pres pres ure, ure, psia psia an lI la be ewri ewritt tten en as
Tz
density,
p,
1O.72Tz
rt
.e
is
(3)
1,544T/M
as: ---, ---,
l.
is
(4)
lb/ft"
AsEq. (4 show show ga dens densit itie ie depe depend nd on pres pres ur an temp temper erat at re Henc Hence, e, fo purp purpos oses es of calc calcul ulat atio io pipe pipe in te es ly this this cula cula iz
Spec Specif ific ic volu volume me is th reci reci roca roca of ensi ensity ty ft /Ib. /Ib. high high temp temper erat atur ures es an pres pressu sure re ga es do no foll follow ow cl sely sely th idea idea as law, law, an :j:. 1. Th nume numeri ri CHEMIC CHEMICAL AL
ENGINE ENGINEERI ERING/ NG/DEC DECEMB EMBER ER
23, 1974
59
COMPRESSIBILITY
critical critical temperature, temperature, ia an 548°R 548°R resp respec ecti tive vely ly We then then calc calcul ulat at redu reduce ce pres pres sure 450/1,073 T/Te perature TR 760/548 .3 find find that that .9 or thes thes valu values es rela relate te th S60g' P60y'
P60a'
un er th
am
co diti diti ns
My
(5)
IIIIUlIIUIJWllllmIUllIlUIUIIIllUJIIIIIIIIIUIlIIIIUlilUlllnml!llJIIIUUlUllllllUIiIWIU!IUUIUIItIIIUHIlIIllIUIIlIlIllII1t1l!l l Ulllnml!llJIIIUUlUllllllUIiIWIU!IUUIUIItIIIUHIlIIllIUIIlIlIllII1t1l!l!tllIIlflt ! tllIIlfltll1llllllllll l l1llllllllll
S p ~ ~ ilil i H e a t Molecular
a t 6 0 ° F . Pressure. Psia /c
I lili IlIl i
f(
so
Temperature.
Acetylene Ai Ammonia
17.03
1.31
Benzene
78.11
1.12
70.91
1.36
64.52
1.19
73
1.657
C a rb rb o n d io io x id id e C a rb rb o n m o n o xi xi d Chlorine
th
y,
le
th flow flowin in temp temper erat atur ur
Ethane
a'
at an pres pressu su e, th rela relati ti
is
where is th dens densit it of th ga at flow flowin in temp temper erat atur ur an pres pressu sure re Th de sity sity of air, air, P60a' is0.0 64 lb/f lb/ft" t" an th mole moleccular ular weig weight ht is 28.9 28.97. 7. Dens Densit itie ie an spec specif ific ic grav gravit itie ie [2,4,5a).
Hydrogen
2.02
Methane M e th th y l a lc lc o h o M e t h y l c h lo lo r id id e N a tu tu r a g a s' s' : Nitrogen
1.40
28.02
Oxygen
49
22
73
27
Propane Propylene
Mixt Mixtur ures es
liqu liquid id-v -vap apor or mixt mixtur ur occu occupi pies es
93
E t h y l c h lo lo r id id e Ethylene
(6)
Dens Densit itie ies: s: Liqui Liquidd-Va Vapo po
E t hy hy l a lc lc o ho ho l
W a te te r v ap ap o
of volu volume me th
=Approximate
1.33
18.02 vaue
Sourc Source: e: "Engi "Engineerin n eerin
ba
on av ag
composition,
Data Data Book-1 Book-195 957," 7," 7thed., Natura Natura Gasol Gasoline ine Supply Supply Men's Men's
Assn.
volume 60
it
occupies,
give give it dens densit ity: y: P v
W/V
lllllllHIIlIllIUtllUlllllll1I1lIHlUHlI!1llllltllllllUllIItlUllllllltllllttlttt!tlllltltlUHlttltllll!IIl1/lHUllIIllllmlllltllUl!!ltlUllIlIHlIWlIIlIllltllllHi
D EC EC E B E
2 3 1 97 97 4/ 4/ CH CH E I CA CA L
E NG NG IN IN EE EE RI RI N
PHASE an
vapo fo
ma eria unde goin
system-Fig.2
1111111111111
ible
Similarly, fo th liquid part Wl+vjV densit will be th mixtur densit becomes: Hv
WzlV Th Since " 1 + 1 1
mixtur
lb/ft"
(Wjp )'
ca represen th weig
(7),
ture. Example water, comp nent
(Wjpl)
PI
(7)
of fluid,
1. crease densit significantl reduce th static head back pres ur in ertica pipe 2. it constant ei ht flowrate an mall amou vaporization th olum flowgreatl increa es In tu n, this increa es pipe resi tanc ignificantly uc
ei ht
Thermodynami 495 lb/h, an of steam, Wv ar el mixe an flowin co currentl in 11 psia "F,
By ub tituting into Eq (4
find that stea
ensity
is: 0.23 Ib/ft3
18(110) 10.72(344 460)1
Properties
outine calculations fo piping an comp nent sizis ly it useful to recogniz he ph sica change take lace in lo if li id it il le iz ly pres ur eduction ca increa piping an componen resistances.
[5a),
By ubstit ti th Pl
Men's
11I1I11I11ll1I1II
RING
is /It. th appr priate values into Eq (7), it 500 (495/55.56)
(5/0.23)
16.3
ENGINEERING/DECEMBER
ta
lb/ft"
is ll 1%)of vaporization greatly reduce liqui density Hence, ig aw at CHEMICAL
is
23, 1974
il graduall np tu
es in is ll vaporize th liquid in
hile it pressu ts
an 61
1IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIImlllllllllllllllllllliUlIIIIIIIIIUlllllilmmlllllllllllllllllllllllllllli1IIIIIIIIIIIImmlllllllllUlil!II1mlllllllllWIIIIIIIIIJI
Typica Sections of Stea
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Tables-Table II
Typica Liquid Velocities in Stee Pipelines-Tabl II
ds Pressure Absolute.
Pressure
'.
Temperature.
Hea of th
a te n H ea t o f
t.
Liquid.
Evaporation.
Gage.
Psia
Psig
of
Btu/lb
Btu/lb
110.0
95.3
334.79
305.8
883.1
111.0
96.3
335.46
306.5
882.5
112.0
97.3
336.12
07
882.0
124.0
109.3
343.74
315.2
875.8
125.0
110.3
344.35
315.8
875.3
126.0
111.3
344.95
316.4
874.8
127.0
112.3
345.55
317.1
874.3
l P
. I
2 or l
dL
FIlS
3 to 1
0 to 2
Velocity. FtlS
Velocity. FtlS
Water Pum
to
s uc ti o
t0
2t 4t
B o i e r f ee d S lo p e
4t
sewe
H y d r o ca r b o n l iq u i d s Pressure Absolute.
'.
Pressure
Saturated
Gage. P.
Temperature. t, of
Psia
PSig
400.0
385.3
--
444.60
76 h. 1 .2 45 .
449.40
p s Di
00
70
21
3.
to
D i sc h ar g e l ea d s (short) 3t
49
1 .3 07 .
1 .3 63 .
1 ,4 17 .
V is c o u o il s P u m p s u ct io n ,
00
h.
1 ,2 42 .
1 ,3 05 .
1 ,3 62 .
1 ,4 16 .
h.
1 ,2 39 .
1 ,3 04 .
1 ,3 61 .
1 ,4 15 .
454.03
440.0
( N o r m a l v i sc o s it ie s )
T o t a l T e m p e ra t u re . of
M e d iu m v is c os it y Ta an
2. to
ue oi
0.
44
0 .7 5 3t
Drains
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
IIIUm llllltlllUilUIlmllllllllllllllll llHIII1I1IU IIlIIIHillUilltlllllllli1U1U IIUnltllllUIIIIlIIIIIIIUlillIU tlllllllll llllflllll lllllHlllllllllll illtllll1l
Ty t, il au
tu in th th te perature an th volu
in of apor
superheated. At higher constant pressure th boilin temperatur il ig er an le heat il required to aporiz th li id th critic oi (see ig 2) th de itie critical temperature, th substanc ju ab ve it is co idered apor
Ve
S a tu ra t e
Vapo
S u pe rh ea te d V a po r o r G a s H i g h P r e ss u r e
Nominal Pipe Size
Velocity. FIlS
V e lo c i ty . F i l
Velocity. FIlS
In or
as
ss
3t
is considered liquid
20
Btu/lb). Thermodynami properties fo variou substances have ee establishe an ar availa le ar of typi al ag
ci gh
o 1
o 1
o 1
o 2 an
th el
ze an
ne de
00 an
70 he
[1,5b R eb o e r d ow n c om e ( l q u d )
Flashin he
R e bo i e r r is e ( li qu i
Liqui li ui
is fl ib
O v e rh e a
in near it saturation poin (als il t)
C om pr es so r
s uc t o n
C o m p re s so r
d is c h ar ge .
nl
greate th pressure difference th greate th vaporiza
s t a m u rb in e
O bt ai n s on i
nt
62
th li ui
32
v/,
p o n t a t s i n ce r
o r c ri ti ca l
v,
ropertie
25
20
0.5v/,
R e li e v a lv e , d is c ha r ge . vave
00
50to 35
as Re
phas flowproblem Th quantity of vaporize liquid ca
a n d v ap or )
c o nd e ns e r
v el oc it y
Vet
from:
68yk(P'
/p),
Itls.
I I I I U l l l i l l f t l l H H l l l l t l l l l l l l l U U l U I I J l l l I I I I I I I I I H l I I I I I I I U H l I l t l J l I I I I I I I J I l 1 l 1 l l l r m t l l l 1 l l 1 I t I l l t u l 1 1 l l l l 1 l 1 l 1 l l 1 l l l 1 1 l 1 1 l l t 1 t l l l l l l t l l l l l l l ll l l l l U l I l I l l l I l I l I I l
D E E MB E
2 3 1 97 4/ CH E I CA L
E N I NE ER I
1111111
111111111111
111111111111
have .aders.
VISCOSITY
FilS
Example
07
F.
045
0100 075
5.69 lb/h
0200
WI
:0250
satu ated
to
wa er
to
Specific
l.5v/
v/,
ea
IIIIIIUIIIIIIII1I
ERING
IN
63
..
and
I m l ! ! ! l l l l U l I l t l l l l l l l l l ! ! !1 !1 1 1 1 1 1 1 1 1 1 l 1 1 1 1 1 l 1 l l l l t l l l H l I l 1 l t l l l H l U l I I 1 I 1 I I 1 I I 1 1 I I 1 I I I I I U I I I I I H l l l l l l 1 t 1 l 1 l t 1 l lH l l l l t l l U l l U l 1 l l l l l l l H I I U l I l H I I I I U l I I I Il I I I I I 1 I 1
Maxi Maximu mu
Velo Veloci citi ties es To Prev Preven en Eros Erosio io M a x i m u m V e l oc oc i ty ty .
at cons constan tan pres pressu sure re At cons constan tan pres pressu sure, re, where b. ta mp an
:::::
b.h/
tu
FIlS
. L iq iq u
c ar ar bo bo nn- s e e
PV
p ip ip e
RT, where
c/c
P h e no no lili c w a t e C o nc nc en en trtr at at e
s u f ur ur i
C o o i ng ng -t-t ow ow e r
a ci ci d
12
w a te te r
S a l w a te te r C a lclc iu iu m c h o riri d Ca
od
b riri n
>5
ol me
A q ue ue ou ou s a m in in e ( m on on o - o r d ie ie th th a no no la la m in in e
10
W e t p he he no no l
60
L iq iq u
p la la s
v ap ap o o r u bb bb er er - n e
p ip ip e
10
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
al co an em quantity expo expone nent nt Data Data fo and in hand handbo book ok [2,3 [2,3,4 ,4,5 ,5cj cj
Fl
tu e)
lo
ar avai availa labl bl
The in engi engine neer er
io
Velocity-A id ipel ipel el it io le ee velo veloci city ty is calc calcul ulat ated ed at give give cros crosss-se sect ctio io flowrate: ft/s wher wher ql.f4, ft/s ft3/S, and Fo liqu liquid id-f -flow low calcu calcula latio tions ns 0.408(
Fo vapo vaporr-fl flow ow or gas-f gas-flo lo
an
li ag stea steady dy
(8)
£i2)
calcu calculat latio ions ns
0 . 0 5 0 9 W/(d P)
(9)
where is velo velocit city, y, ft/s ft/s is volu volume me flow flowra rate te gpm. gpm. is weig weight ht flow flowra rate te lb/h lb/h is inte intern rnal al diam diamet eter er .o pipe pipe is ga dens densit it at flow flowin in temp temper erat atur ur an re sure sure lb/f lb/ft. t. Th rela relati tion onsh ship ip betw betwee ee volu volume me flow flowra rate te (Q gpm) an weig weight ht flow flowra rate te (w (Qp/7.48)60
8Q 0.125(W/p)
p/
P60w'
500QS. 500Q, it Pi;ow 62.37 62.37 lb/ft." lb/ft." Th init initia ia pipe pipe diam diamet eter er ca be esti estima mate te by choo choosi sing ng reas reason onab able le velo veloci city ty fo spec specif ific ic type type of pipe pipeli line ne Thus Thus fo liqu liquid id line lines: s: in
(10)
0 . 5 0 9 W/( up), in
(II)
0.408(Q/u).
Tabl Tabl II give give prac practi tica ca velo veloci citi ties es fo 'liq 'liqui ui line lines, s, an Tabl Tabl IV fo vapo vapo line lines. s. alue alue of and ar tabul tabulat ated ed in pipe pipe manu manufa fact ctur urer er cata catalo logs gs [5f} ll
ch ca ed th mu ed Ta li e. Viscosity-Viscosity liqu liquid id or ga flow flows. s. me in tance ance of flui fluids ds With With incr increa easi sing ng temp temper erat atur ures es liqu liquid id vi cosi cosity ty decr decrea ease se an ga visc viscos osit it incr increa ease ses. s. Fo meas measur urin in visc viscos osit ity, y, many many Engl Englis is an metr metric ic unit unit el ie en be used used conv conven enie ient nt conv conver er io cale cale betw betwee ee th vari vari it es
FLOW
64
ai
ig
MB
3 , 1 97 97 4/ 4/ C
MI
IN
IN
(12)
piS
where and
is
isco isco it
in cent centis isto toke ke
f1
/s. is f1
[5d].
,nol ,nolds ds
re
umbe umbe
Fric Fricti tion on Fa to
re
rp
fl
is la
ic (Fig.4c). eyno eynold ld
numb number er
RELATIVE roug roughn hnes es an fric fricti tion on fact factor or char chartt-Fi Fig. g.
Re
.t
s,
0)
1)
ld
re
he st-
-isiits vill an-
FRICTION
fact factor or fo an
yp of comm commer erci cial al pipe pipe unde unde an cond condit itio io
ING H E I CA CA L
E NG NG I E E I N / D C E
ER
2 3, 3, 19 19 7
of flui flui
flow flow Fig. Fig.
65
is dime dimens nsio ionl nles es comb combin inat atio io of pipe pipe diam diamet eter er velo veloci city ty DUP/fLe' dens densit it an visc viscos osit ity. y. Re where fL bsol bsolut ut visc viscos os Ib /(ft-s)(ft2). Prac Practi tica ca formu formula la for calc calcul ulat atin in Re are: Re
50.6(Q/d)(p/Jl)
6.31
Nominal
Friction
Nominal
Friction
P ipip e S iziz e
Factor
P ipip e S iziz e
Factor,
In
where we gh flow flow b/h; b/h; is nter nterna na di me er of pipe pipe n. is dens densit ity, y, lb/f lb/f and viscos osit ity, y, cp fL is visc esis esis nc flui flui ot on depe depend nd on he type type of flow flow Rela Relati tive ve roug roughn hnes es is €/ where he bsol bsolut ut roug roughhne (i.e (i.e., ., th dept dept of he unev unev nn ss of th in erna erna pipe pipe wall wall), ), an and shou should ld be easu easure re wi he sa di ensi ension on unit unit Valu Valu fo rela rela iv roug roughn hn ss be ob aine aine from from
obta obta ne
I l I 1 I B U I l U I I 1 1 1 I U l 1 1 t 1 1 1 l l l U I ! I I I tJtJ I I I 1 I I 1 l U l 1 1 1 1 l l 1 1 l lU I I I I H I I l I l l l l l l m l t l l l l l U I I I I I I 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I I l I I l U l I l l lU 1 J l m I U H I I U I 1 I I I I I I I I I I I I I I H U I l l I
from from Fig. Fig. 6, fo vari variou ou flow flow ondi onditi tion ons. s. 2,00 2, 000, 0, th fric fricti tion on Re
64/ Re he Re .;;;; 4,00 4,000, 0, th fric fricti tion on fact factor or is unpr unpred edic icta tabl ble. e. Fric Fricti tion on fact factor or
In
W,
0.0205
10
0.0136
0.0195
12
0.0132
0.0178
14
0.0125
16
0.0122
0.016
18
0.012
0.0152
20
0.0118
24
0.0116
11l1I1lJlIUIIlIHUllllllllllllllllllllll l llllllllllllllllll l llllllllllltlltllll l ltlltlllllllJlll1HltlIIIIII l llJlll1HltlIIIIIIIIIIIUUlllmlmm1 I IIIIUUlllmlmm1 1111111IU IlIUlUIIJIUI!I!llIlmlllllllJllIlIllil J llIlIllillmmJIIIIIUIHlI l mmJIIIIIUIHlI
manufacturers [51]. th re om enda endati tion on ards nstituteo
of he Amer Amer an Na iona iona
pipi piping ng an comp compon onen ents ts Prac Practi tica ca form formul ulas as will will be give give fo liqu liquid id-l -lin in an vapo vaporr-li line ne sizi sizing ng fo whic whic th dens densit it
Acknowledgements
Re
ns
ig 6, th flowis flowis in th rans ransit it on urbu urbu nt one. one. er th fr tion tion fa or vari varies es wi he eyno eyno ds nu ber. ber. Th nd th fr ctio ctio fact factor or re ains ains onst onst nt with with in re sing sing Reyn Reynol olds ds numb number er ec us gl ss nd pl st mate materi rial al have have smoo smooth th pipe pipe re at ve roug roughn hnes es or pipe pipe di
et r. Henc Henc
tand tand
xt
L. F.
here here is on
References
[5e].
diam diam te
in
il repl repl ce he onst onst nt re at ve-r ve-rou ough gh ns
borderline
Re
Fr tion tion fa or in he to al
3. "A.P "A.P.! .! C.
na
., "C emca
e er er s
,"
turb turbul ulen en
Example
B-S, (I)
1=
th fr ct on fa to mu
be ob aine aine
from from Rober Rober Ker is
neer neer in th
diag diagra rams ms ar used used in calc calcul ulat atio ions ns wher wher th pipe pipe mate materi rial al
eros erosio ion, n, th fric fricti tion on fact factor or shou should ld be incr increa ease se by safe safety ty fa or Fo team team onde ondens ns te ooli ooling ng ater ater al wate water, r, size size nd th
xpec xpecte tedl dlif if
of he ns al atio ation. n.
engi engine neer erin in
numberof numberof articles articles in thes fields ha taug taught ht seve severa ra cour course se fo desi design gn of proc proces es pipi pipi g. plan plan u t g ra p i c i pi pi n a n f lo lo w s, bo in he U. ci Engl Englan an an th
and th laylays ys ys ut
lo U.S. U.S. Mr Kern Kern ha
an M.S. in mech mechan anic ical al
he 66
senior senior designengi designengi
corp corpor orat at
depar departm tmen en of Hoffm Hoffman annn- La Roche Roche Inc.. Nutl Nutley ey NJ 0711 07110. 0. He is spespecialis cialis in hydra hydrauli ulicc-sys system tem design design si
engi engine neer erin in
Budapest.
E MB MB E
3, 19 4/
E MI MI C
IN
RI
:~ases in pipelinesundersteady-flowcon\ns.,
/'
ft
ROBERTKERN,Hoffman- La Roch Inc.':'
manufacturers' literature an
in ec thos acting agains th flow ar
in ha dbooks
at
in em ti il ap ly tica formulas fo izin th components of such sy tems when handling liquid an vapors
.l
'5:,F
Eule 's Deriva io
egative:
Pd
d l sin
in
an
ea Pressure,
mass, dm, En li me em ia ma
id is en
in
is dA. and aralle to it directio
of motion Fl
dp), and
(p
-_
p. to show
dl,
b. Differential Quantity Enlarged
ei
dp dA
~"., sin IX sin IX. force, hich is th flui 's re istanc acting agains th io 0.) Perpendicularl to th X-axis, ct th al each other, i.e. 2: dm (i.e., cos IX), er en ic to ir io lo Chern. Eng"
CHEMICA
(1)
dm__
in
pressure, (p
iv
Dec. 23 1974
p.
66.
ENGINEERING JANUARY 6, 1975
dz
FORCES acting on ifferentia
as in fl id-Fig 115
Point, .1
Ip P1
2g
zo al
pe
DISTRIBUTION
length, dl, is dz
dl sin ex, (2)
'iF
-:iF
adm; W i g ; an acceleration is th velo tional constant: do dt Concity difference dv, sequently, '2,F (W g)(dvldt). Sinc th weight.o flui is it ol me ulti lied de ity: 'iF
(3)
dA dl(plg)(dvldt
pd
where dlrd:
c . P ip in g T ur n
(5)
dz
relati ns ip
fl id lo
as develope
by
ga li es
er
iq id re ur losses ar mall
pi elin late in this arti le 2. Wher en it cannot be co idered co tant pressure differ ntia is izable betwee is
Bernoulli'
energy dist ibutio Fig.
tw
hi
oi ts of th la
Equation
constant yields Bernoulli'
equation dz
Pl)
(z2 -Zl)
(2 in
ipelin
pressure differ
it constant diameter el city uall VI Th fi st fact chan es
th componen fo th velocity-hea no becomes:
head differences, respectively Eq (6 is used fo investi-
difference (7)
designer's standpoint Head loss expens re ure- ea tatic-he differ nce. Th tatic-head if erence ca ositiv egative. negative static-hea difference th pressure-hea differ th h£ ractical esig ork, Eq (7 ca ra el be ul ille 1.
greate than th re istanc
116
or calculatin
Fig. graphicall illustrate Bernoulli' energy distri utio in la te pi elin it tw additi na factor
1.
an th
affect
gating energy distribution
uler
basi ways
line
PIPE elevatio
o wn wa r
to lo
Do no us up velocity head fo pipe resistance
2. Commercial pipe ar manufa tu ed in increments of size (i.e., pipe diameter). Consequently th calculated s am e di Eq (7 becomes:
o,
po (8)
h an d po nd pipeline Resistance should be calculated fo al alternativ
he di of du sure: Zz ng ns do Zl' of low,th st ti he adds pr ssur to th luid
of flow
on Zl
Zz
calculations. .r>.
of
pe ne
g en e
sr,
tlPa
tlP
where /:"P is'fhe /:"P pr dr ue si nc /:"P is th excess pr ssur drop ug q u m en t n d o m o n pipe system ls introduces additional resist nces that
FLOW
10
/:,.P
resistances, th overall tlP.
/:"P
tlP
dist ibutio tlP
tlP
tlP
where
/:"P
and
ur dr ue si nc pi om on is pressure drop du to resistance in equipment.
/:"P
/:"P
qu C(2gh)
«v-».
(1
an be
of liquidthrough pipe or orifice-Fig.
liZ,
Flow coeffici nt or piping an pipe components ar bt om xp da or ns s, or nt usua constant is When sizing pipes, th lo coef icient, K, is proportional to th rictio acto .j', an pipe length, diameter, D: K==JL/D
"f
qu
he
om of he
nt
(11)
(Che n. En .,
ho
z.
or
of
pipe wall liquid leve move down very slowly
nd it velo it
VI'
atmosphe ic at th liquid su fa nd th bottom outlet PI and, consequently O.For convenience, we will ur nd bo op hL thes actors into account, th Bernoull relation reduce to
Taking q. 6) (9)
nc
ot vi
ua
q. lettin hL
th
Formulas
convenient unit
by
gl sh
surement. We il begi by converting Eq
10 to pressure drop
/:"P, I:lP
ui
To ge pressure drop / : " P ,
ps or
(fL/D)(u /2g)(p/144)
I:lP
(12)
( h L P ) / 14 4
uc ng
pe
om (13)
(10)
Ku /2g
CHEMICAL ENGINEERING/JANUAR
used by design rs manu actu er
ns
nt on
ou anc coefficient, K, an
Practical
.w
6,1975
117
velocity.asa volumetric flowrate Q, gpm, we substitute (13). These 0.408(Q/d D==d/12,arid substitutions.now yield:
IfIlHtlllU1111111111111111111111111tJ1ll1111l11\\1Ulllm1l1111111111UIII!IllUjlllllluml!lIllllllllllUIIIIIltlt11 l11ll11l11l11l1l1l1Ulmll\\IIIIIIIIllJJl11l1Ullllll
Resistance sist
90
in
of Elbows quiv le
ip
ee le
E lb ow s
N o m i na l
90
long
B en d
111,
pipe ength; t;
..J.L
is densit lb/ft";
Fl( Vi~
co 10 ft
11 3.
3.
13
D.PlOO
O.0216fp(Q2/d
),
psi/IOO ft
(15)
q. (1 ca be ex ress in term of sp ific gravit by substituting 62.37
10.5 15
an fa
(16)
21 24
10
Ex
at th flowin
2.
2Y
Sp De
is friction factor is is volumetric flow
an volumetric flowrate must be expresse temperature.
Through
Branch
4.
Sp'
(14)
Flow·
R= 10
In
ft
SUl
14
16
25
62.37 lb/ft", is
21
60 F.
nc
th
pe ific ravi
at
in
22 39
16
26
21
26
29
24
29
q. (1
12
Fo or
5 ° e lb ow s a n b e d s e st im a 50 o f t ab ul a e d 80 returns, double th tabulate values
16 ar th most onveni nt or
lc la
manufacturers' catalogs. Example
32 60
an
in'') line
(J.D.
38
60
v al ue s
P60
(=321°F.
1IlIIIllHllIl\IIlI lI!1II11II IIIIl11\\\1 111l1111 1H!llUlI1 111lIUlltU IUlIIIlI1 l111[llUllllllllll!U\llllllIlllJlllJIII11Ill1l1111 11111n UlUIlII IIII\1U lllml\\l1l11l11 t1
I\lllltllllllt11111l111l1ll11lIlllill11lUUllllI1UI1l!IHI!\UIIUII!lI1111IllUIIII1U!l1mIII1\UlIlU!n!!tII11lIlUlII IUlllltlItI1!UI1IU\l11\l111l1llIlUUlllmlml\\\tllt\lIt1I1lIlII\UIlU\lI\U11U1II11I11Ut\IlIUH11111UU11I1IIHIlIIIII IUJIIIU1tJIIUUmUllIIUI11IllUllUIIllIl1III1I11l1ItlltllllllllllU\H11!J11l11l\111l11mlllllU1U1II1lIllU
is Globe.
ce
in
ivalen
Pipe
Check Straight·
~o
In
Straight·
60
2.75
70
3.
90
4.
Flow·
tI Op
2.
2.25
tl
C o ck '
Ball
~o
1.75
2%
ft T h re e· W a
Gate.
111,
le gt
F u ll y O p e n .
B ev e o r P lu g S e
N o m i na l
ip
ti
20
is
30 35
38
12
36
12
12
23
12
10
95
15 14
14
15
90
13
12
14
14
38
15 22
18
18 20
24
29
24 l os e
v al v s ,
va
30 38 40 17
20
17 18
it
45 50
21
20
64
25
78 lt
pipe area 80
UI1IU\\1III1I1U11111I\\1IUlIUtlJIIIIIII1l11l1111lH1IJIllUIlIIIUlUIIIIIIlIHIIIIIIlIIlIlUlIUlIIIIlIIl!IIllIIllI1I 1I1lUlUIUllIIlIIIIIlIIIIll1tl1U1llUllUllIIllIIlliUtlIIIIIlIllII111\!l\IUlIIII1ll11l\l\IIII1II1Il11Ullllllllllll llllllllllI1l11111l111\11UllllUUlIlIllUIIIIlItIllUl1l1lllltlllulmu\lIIumI1ll1ImUlllUllIJllIlIlIlIllIIlIlIlIlIll l
118
ti
Ii
17
12
(.
.,·-.:JANUARY6, 1975/CHEMICA
ENGINEERIN
r m I U I I U l l I I l l l l l l l I l l U l l J l l ! l l U U l I I I I I I l I t t I U U U I f J U I I l I l I U ] I U l U l l l l l l rm I l I l I t l U l l l U l I l l I I l I I l U l I l I l I l I U l l l l lJ l l l l l r m J l l l l t l l l l l l lm m l l l l l l l l l U l I U i
summarized as
Resistance
Specific gravit at 60'F S60 51/62.37 0.82 Specific gravit at 321°F: S 3 2 1 a, 1.' Densit at 321°F: 62.37(0.72) 44. Ib/ft Expansion factor 0.82/0.72 1.14 S60/S Flowrate at 321°F: 900(1.14) 1,026 gpm Qso/E Viscosity: 1.'
Wenow calculat th Re nold numb conditions:
of Ecce
(Resistanc
In
d,Ejd,
d,
Re
50.6(44.9/0.3)(1,026/6.065)
Re
1. 81X lO
ic
ft)
d,--dz
dz=t:::: d,
Sizes,
Yz
50.6(p/p.)(Q/d)
Co ce
in equivalent pipe length
Nominal
th flowin
Re
ic an
d,8
0.
0.
0.
0.
1.
1.
1.
0.
);,
y, 1Y Re
of seri s, nd hence, 0.0154. (Flow al in th ransitiona tu bu en on .) Substituting th ppropriate values into q. 16 ie ds t,p 100
1.35(0.0154)(0.72)(1.026)2/8,206
t,p100
1.92 psi!
1. 1);,
1.
1);,
3.
1. .4
2.
2.
3.
in (f4)
O.l25(W/p)
nt
t,p
nd
where I1P drop psi/IO q. 17 that (l) (P
po nt
th m.
hi
onve sion
q. 17 be omes
MlOO
0.OO0336(j/p)(W2/d
15 9.
(18)
I1PlO
ft
P2)/2,
(17)
0.OO000336L(j/p)(W2/d
10 ft
12
ields:
is pressure 12
vi where
is th dens ty
19
12
14
12 6.
th beginnin
nd
14
22
14
22
14
27
17
23
17
15
15
15
15
13
13
25
25
0.4P becaus energy losses du to accelera tio'" ',a J.ddens ty va iation an be neglecte up to this 10
ur tion ar done by consid ring ha th line is divide into
14 10
course wi be diff rent in each segmen 0.IP If ve ag values of al ul ted. ithe th do nstrea or upst ea ca .b used
12 18
densit
14 16
Example
12
4.02 in
1,05 in") ga 10,750 lb h; mo lecula weight 16; temperature, 172°F; pres sure, 12 psig an viscosity, fl 0.0145 cp
14
20
16 18 18
24
densit at lowing conditions
nd th
pipe an ar
is
ea
ER
C he rn . E ng .
12
iction factor
Dec. 23
1974
it
he qu components
le
le
he
iv le
le
he
le
J l J l l U I U I I I U l I l U U U I I I l I U I I U / l l l l U U l H l I l l J I W m l m l l l H l l l l t / J I U J U l l l U l I l J I I I I I I J lI I J l I I U I l U l I I I I I 1 l I I I l U l U 1 1 I I 1 I I U I I I I I I I I U J I I I I I I U I I / l l m l l l l l l l l i m
119
AR
Ph,;:
;ealQ4,;;;U
, . P .4 M
)4
t_S#_
@ l4 , . . ,g;;S;
44P_.W?A
Q4iZ
Qt - 4J ! 4 .
;"
4t.A
U l l 1 1 1 l U l l U l l ! l l 1 1 1 1 l l l l tl l l l l l l l l 1 1 1 1 1 1 U U I I I I I 1 \ 1 1 1 ! 1 1 m U I I I I I I I l I l l l 1 1 1 1 1 1 U 1 t t l l 1 l 1 l 1 l l l tIt l t l \ l I l 1 1 ! m l \ n !
Resistance
lIlUnlmllll\1I1 !11~hlJ" lIl1ift'uu~tltlI11\11lfl1
ve,;tic~r
Horizo al an
Resistance
in equivale
pipe le gt
ff)
Resistance
y:_:
f= 0.23
Coefficient
1.
Nom ina
---,
P ip e S iz e .
--r=:
---.
0.
1. :y
2. 4
1.
0.75
3,5
1.75
is comput d. th Clxerallp essu os "i lose to an less than the. availabl:e pressure difference betwee tw points in pipeline select size is accept fo th give flow conditions In pipeline calculations it is convenient to obtain pres Multiplying tlP100 by tlPlO th equivalent length of pipe an fittings (L, ft) betwee tw po nt ie ds th ov rall pressu loss t::.P
t::.P lO (L/100),
(19)
psi
Th equivalent-pipe-length concep is th quickest an most convenient method fo calculatin overal pressure
3
111,
5.
15 20
16
10
36
29
18 12
48
th tw ends of th piping component. Si es re assume to be identical. of he nc ng from Tables to IV he b l h av e Example
pr
15 12
78
60
39
19
70
44
22
78
50
25
as sketched here
34 13
42
85
1 t l 1 1 l 1 l 1 U 1 1 1 t 1 1 1 U I ! U I \ I l U l l l l l m l l l tl U l 1 U I I I I U l l H l t n l U l l1 U l I l l l t lt l l l l 1 1 l l! l U I I I I lI l 1 ! ! 1 1 1 1 l I I 1 H l l l lt I l l l l l l l l l l l l l t l I U I I U I !\ \ ! ! ! u I 1 l IU I I H l I U l l l l I1 1 1 1 1
A l d im e n o n
temperatur
ng re in abso ut units: MP'
ha
1 0. 72 T
16(127 10.72(460
14.7) 172)1
0.334
Ib/ft3
Reynolds number Re
6.31 W/ d,.,.
Re
(6.31)(10,750)/(4.026)(0.0145)
ft.
that th pressure drop fo th 100- oo length of th pipe tlP 100 1.92 psi. From able I, dete mine th quiv lent pipe length de
th
re
U s e l o ne -r ad iu s e lb o w s
Re
ou we get:
sy
Actual length
78 ft
o ng -r ad iu s
e lb ow s
f lo w- th ro ug h
t ee s
60
158 ft
en
th friction factor
is he
ft
20 ft
0.0166.
we obtain:
1.92(158/100)
04
on th resistance coefficient, K, K=fL/D,
nt
t::.P
t::.P lOO
0.000336(0.0166/0.334)[(10,750)2/1,058]
t::.P 100
1.82 psi/IO
ft
ng
O v er al l P re ss u r l os s
give se of flow onditions,
nd th overal pressure loss
itting an othe ance of luid lo 3, 97 with orifices an
120
,, JA
omponent ontributin to th resist an be accurately added, vi flow nozzles, RY 6,
9 75 /
me E MI C
E N I NE E I N
CHEIII
aximum
iffe en ia
ss
an
si
.f
in
in
eas
rp es ozzles
Flow
€)
e. ea tems must provid equall important,
te lo pipe diameter of ufficien size and, suitable configuratio fo th piping amin amet in at to th sizing of orifices an flownozzles in piping systems. th lo irede uate traight-ru flow device
of piping before an afte th
ipin
ific
izin
Jan. 6,1975,
Ku
p. 117) to ex ress th
flow velocity as (1)
Pr vision fo orific taps separato chambers it to l ll
trai htenin
vane in
an en
te
where
Vf!K
C, th orific flow coefficient. (Chern Eng. Dec. 23 1974, p. 64), we find th velocity-of-flow formulas (2)
twee
pair of flange
thick) Minimu la
ig ly
Usually, this orific is
orific bore is usuall in If required an ar ll ific ap
la
es la
th
to
in lo
2. fluid, th pressure difference betwee
0.0509
stainles
/(ct;,p)
portiona to
where passin throug if tw
19.67Cd~VJJ;_
(4)
157.66C~v1l;7
(5)
W,
give orific bore (do, th tl id th
th
es L' ft.
(4)
th inle an outlet
meet your author se . cn em . E ng . . Dec 23,·1974 p:66.
selectin th orific bore an metering range, or fo sizing ipe, th followin change ar nece sary 1. os orific ma ometer recordin an transmit ting instruments) ar calibrated to in icat th ressur F EB RU AR V 3 , 1 97 5/ CH E I CA L
E NG IN E R IN G
OR FICE mounts be ween pair of flanges-Fig.
ES UR
is ib io
lo
orific
un Fi
°F in Thus hrop
(h",/12)PGOto'
Valu
or:
ro fo th
fi orific
flow coefficient,
C, ar
st blishe
NR (6)
Fo
liquid
Re
hI,
fi
(7)
(h",/12)(l/S)
re in NR
(d
),
i.e.
do/d
or
hI
pipe. In practica
and do
applications Re
(5 yields 5.68fj2Cdy(Vh:;/VS)
(8)
359.43f12CdiVh::P
(9)
100,00 ar capacity coefficients For f3
0.7, f 3 2 C
is: (3 Eq
For (3
8) by S/SGO
fluid-flow
0.75, (32C
calculations.)
(32C,
0.339, and: 926di(Vh:;/VS)
(10)
121.87dh/h,:;p·
(11)
0.406, and: 2.31d~(Vh':;-/VS)
(12)
145.93diVh:P
(13)
h1
Fi t,
fi b.
or b.
E NG I E E I N / FE B U A
3 ,1 97 5
(h /12)(62.37/144),
0.0361hw'
re H E I CA L
valu
fo
NRc>
(d,,) to do
00,000 th
re 73
..
acro th orific plate. As th high-velocit je from th orific impinges upon th slower downstream fluid, some of th jet' kineti energy converts back to pressure Thus th es an th
Nomenclature do
d,
0.7, th of th orific pressure differential ti er ak lo
permanen loss is 52 Second, hw ia
or measurin at maximu measurin iq id
ra ge greate than th calculated deflection flow At orma lo th de lectio houl
range. Practica instrument calibrations rang ea
id ti ic iq id ad stream of th orific ca overcome possible vaporization Liquid-vapor mixtures cann be eliabl measured with differential-pressure producin restrictions.
en
te
ft
Differential
S6
lo
in
Specific e ig h
id f 1 w ra te , l b/ h
f3 f32C
P,;o
Ca it Viscosity, cp it iq
lo
it
lb/ft"
p(;O",
FU
larger flow capacities If th availabl
ce
in di charge an (9 reveal thre adjustment
ic
psi
hw
fi
ar
tiPo
p,
in
ie
hL hw
to orific flow capacities
1. Increase Line asin li entire straight-run of orific piping is th mo expensiv tm th is te ce to ac
er ec mi manomete with al ca th me ma
pressure difference
mp high de lectio mi ht no ti ty th i-
to fice. Th formulas fo estimating orific deflection from Eq
dia.,
ip iz is ly ip diameters, an increa of tw pipe-sizes is also po sible. ny increase in pipe diameter should be closel followed
2. Change Manomete Range-An change in manomed an ered es al
Vh::
..,fh,;
ig
3. Change
0..0
<1
10
'>-
'>-
f-
f-
yp),
/(dif3
0.00278
standard 60°F (S60/ S)2.]
in 1-
.. (j
'" ru
ro
::
OJ
0..
0.2
da/d,
it ca ty ie {PC, in If orific pressure differential an th percentage of permall ea me at
Le us design an orific installati fo it 3-i Schedule 3.068 in, d1 9.413) pump-discharge line Flow 50 lb/ft", 0.8, fL 1.3 0.7. fPC 0.339. te ey er th appropriat values into NRC
Re
FE
sele
est, rei, 6.P,
Ratio-Any
OJ
iil
On
(15)
.9
(j
Eq.
2.1: cak
'/z
[I instrument deflection is calculated fo liquid-flo calibration, hw ti ed
Sin exc ges
50.6(Q/d,)(p/p,) 50.6(160/3.068)(50/1.3)
9 75 /
MI
101,500
lo
1113
in inle indi adv con 600/, orif defl doe sun for
IN
IN
in pensation. to replac than th thin flat-plate orifice. To replac flow ti lo nozzle ca handle li uids it high vi co itie an luid it om ntrained olid he ar uitabl fo high-pressur an high-temperature services fo saturated steam, an fo high-velocit flui measurements Thei applicatio migh be useful at existing installation wher ip izes ar to mall fo quare-edge rifice Fl w-no zl capacity an ipin ar size in th am wa asthe components of orificesby usin Eq (8), (9), (14) an (15) as applicable than Reynold NOZZLE
0,00
alue
sually attained ly
it ou diffic lty.
number
mounts betwee
Si ce th calculated
btaine from Fig. 3. Fo feasibilit in ma ufactu ing, commercial size of flow nozzle ar limited. Th follow
flanges"':'Fig.
eynold number is considerably in
le
Vh;;;
7.9 inl/
0.176(1601 v'Q.8i/(0.339)(9.413) hw
62.4 in.
hw
electe is 10 in dol d. Since calculated: tiPo
th manomete
ca comput
rang
do as 0.7(3.068) or
0.0361(62.4)
relation to ti
0.70 52
ti
f:.P
0.52(2.25)
1.17 psi.
(100/62) 1.17
Betwee line-siz flanges,
of actual ti for:
1.88 psi
flow nozzle is held in plac ll
advantag
of
it flow nozzle istha it flow coefficien (and
ic deflection th flow nozzle requires smalle rati than oe an rifice late onse uently th erma en re te le
iz IN
19
STRAIGHT-RUN
eeds fo
orific
pipi g-Fig.
75
CE R E FR E SH E R
Vena Contract
Taps dia,
varies wit
ld
Radius Taps:
Corner Taps
dia,
r-2Y:.pipe cli".-l>I-""'----__;_-8
pipe di
---------1
pipe dia•.
Line Taps
in
averag
ratios an
capacity coefficients f 3 2 C
can
Orific Coefficients [1 ha publishe pi
{J {J2C
ipin
esig
or
perimenters. Th American Ga Assn (AGA)-American
an
ip
Co figu atio
on
ential-pressure flow-measuring element. of th orifice. Th straight length increase with increasing rati (i.e., ld ). ni before he orif ce is ffec ed by pipe onfiguration nd oc ng re Th straight-lengt requirements afte th orific also increase with increasing ension us five time th pipe di eter fo al ratios,
standard arrange-
on required straight length of piping fo orifices flow nozzle an venturies. ld rati of 0.7. Practica GA-ASM ch dule fo orifice-piping arrangements usuall fall into on of thes onfigurations. Th dimens on ho in Fig. re ls suitable fo ratios sm le ha 0.7.
Economy 01
ipin
.ayout
rge-diam te piping it heav al th ckness or fo expens ve al oy piping Occasional quip en oc tions, pipe connections, an predetermine distance ca also intluenc orifice-piping dimensions Th minimu straight-lengt requirements ar only possible if th do
calibrated piping minimu
dimensiona
requirements
Ga flow emoval space
.!
u,
f-
U'-type control-valv
orific
assembly
bore L iq ui d
fi
lo
in to
fo vapors
ll le gt
of inte co
ecti
ol
give th
malles
eflectio
Accessibilit
inst umen
in. ecte
Separa~or Chamber
to
rifices. ft
un
tUbi g. Fig.
i ni mi z
.•
an it in te ed th di ferential-pres ur cell This in tr ment is mounte in th proximit of th orific flange (Fig 7) in an accessible location. Differential-pre sure cell an manometers sh ul be locate relative to orific flange so that interconnectin
~ t ~ ~ . 2 . . · . · t : : r !f-------l ':, Meta pipe (thin wall)
ca
Pipeline Multiple-Tube
Straightenin
ed ca le im affect trouble-free instrument operation.
is
Vane
la at ea ab clos to th orific an contro valve. Spac requiremen is ar Tr mi te an trollers should be accessible
Th
traight-length requirements enable th developmo in ma
.Cover
straightenin ea rack abou .5 two th ir if an ar id (o in tw levels in yard piping th minimu horizontal
vibration. Wher only metering flange an taps ar provided an only occasional flow indication is needed access by port able ladder is ufficient. Locall mounte indicating an measurin flowmeters ar mo frequently in pected If necessary, permanen at ac id is te ar instrument fo measurin flow in rocess feed lines, produc lines, an utilit lines.
it
as in le
an
en
th
ts
present. Th same flow conditions ma also be develope with straightenin vanes, whic requir shorte straight
li co function an
et
id
le tr
henc
ep ts ll am ir measurements will be inaccurate
vane an only slightly correcte
if er
li ly ex
in th shor at er
la in
ci ib ti ca ta th tr enin vane preceded by an elbo Manufacturer of thes ic ca ec en ll ti ct ce at an me il iv th ASME schedule [1]. 3, 1 9 7 5 tube
pito tube an rotatmeters,
References I.
p re nk le , R . . , P ip in g A rr an g m en t f o A c e pt a l e F lo w M et e Accuracy, Trails. ASME, 67 34 (1945) l, American Ga Assn., Arlington, Va., 1963
Chem Eng.
sufficient. Locall mounte
indicating recordin
an
tran mit-
constant
wher
(",,Ie,,. 0.0509 W/(d p)
p.64:
0.0509 W(vp), in."
mp al
it er ca lca an at es ar ls ai le lo ly mo ly mo te
it
i n Ibn/(ft-s).
(9) (11)
f~
'I\l . . , , , .
e"
Ar>.,'
ipin
I!OI
layout st ea li e-fl
associated inst umen
co
an
co
itio s, ec io s. ,~~
~~
ROBERT KERN Hoffmann-L
or meas ri
accurate
lo
fl
in roce
mete in
line
Roch
Inc.
us co ider
ig or th job. (Chern Eng.,
th
ti venturi, it velocity increase an pressure decreases. Th resultin differential pressure is proportional to th flow at nd is used fo lo mete in
in
72),
enturi
pito tubes, fl
tube an
temperat re an hi h-pres re services ompa ed it ot er entu mete s, it co is lo ha hort ve al length nd hi re ure- ec ve characteri tics This
rota eter
en ur Flow Me er
ic entu
is ve
small; an in
ll-d si ne
fl shed intermittently in.
much ig er ca acit
izes rang
fr
to
yste s, venid
ha dl
vailable
ra
in ustria
applications
he lo
pressure
ra ge (10 to 1; some even
20 to 1) than orifices (4 to 1).
erly:
om th ll
ta dpoi
pi in
esig
mu
esol
ve tu
is no as se itiv
to irre ularitie
in th velocity
th di ch rg
coef icient tays
th flow data 2.
configuratio withou additional pipe length an fittings Th alculati roce ures ield th iameters fo th inle pi an throat of th vent ri anufacture s' cata
ratios.
of ventur [1].
sectio an throat metering accuracy is scarcely by upstream flowdisturbances. Both ar availabl in from to in. Fo high-pressur an high-temperature services previously describe meters ar also availabl as welded
Co me cial
en ur
eter
Th ventur meter' (Fig 1)consist of shor cylindrica sectio having high-pressur connection an inle cone
id
·T
lo
an
be au
meetyour author se
Chern. Eng. Dec. 23, 1974, p. 66,
161
CE REFRESHE
Inle
.•
cone-...,
L o w- pr es su r
H i gh ·p re s su r
ta
ta
a. Ventur Nozzle
b. Short-Form Ventur
Low-pressure
c. Long-For
b. Welded
R ef . 1 ]
Ventur
DAL
f lo w tube ha
high pressu
Sizing proced re
fo
differential Fig.
enturi
eter (o an di ferc re
.t series (Chern Eng., umer ca va ue fo
he flow coefficients differ an
e, th
orifices. al R ef . 1 ]
d. Flanqad-Insert Ventur
Liquid
at flowin temperature:
..;Ih,;
(1
S), gp
5.68/32Cdf.(
ic
0.176(Q·vs)i(dif3 C),
in
(2)
Vapors or gase at flowin conditions ec an
359.43f32Cdf.
V'h,;
ec Th an
differen ia
v'h;;Ji,
0 . 0 0 2 7 8 W/(dif3
yp), in
(4
pressure across ve turi
eters, I:.P
re .P
(h /12)(62.37/144)
ps
0.0361h
zi
(5
co
en
venturi. 162
id
M AR C
3 , 1 97 5 C H M IC A
th,; most > 1 , .
EN
E ER iN G
Nomenclature ri i am e Gravitationa constant 32.2 ft/s om lo
do
hw (K,/v)
S60
f3
diameter of pipe Capacity coefficient fo venturi Flui densit at flowin onditions, Ib/f iqui densit at 60°F Ib/f it 62 b/
j32C
Pressure Distributio
P60
Alon Venturi Tube
Capacity coefficien for Annubar Differential pressure across ventur meter, ps Volume flowrate at flowin temperature, gp Specific gravit of liquid at flowin temperatur Sp cifi gravit of liquid at 60 Weight flowrate lb/h
P60w
0.7 0.6 o,
f3
Th
0.5
maximu
f3
0.4
?: 0.3 'u ro ro
cal-upflow or -downflow: or inclined position providin
0.2
as horizontal.
0.1 Dall flo
ta
tube
0.3
0.6 Ratio,
0.7
le ig
ee
dpld1
(3
Permanen Pressure Loss Throug
Ventur Meters
'" Short-form ventur tube ventur nozzle 80 \---,...".,-+---120
te with f3 ia eter is adequate
Straig te in
(3
(3
L o n q - t o r r n venturi,short-form
venturi,venturinozzle (320 Flanged·inlet,enturi
(32C
Dallflow tubs
(32C
0.12
0.2
0.67
0.148 0.2
40 4.
33
240
EE
straig
un equa
vane ca reduce th re uire
up trea
Chern. Eng 8) Configuratio of th do nstrea piping ha no effect metering accuracy Reducers elbo ca be la ge
/MAR H3
valves locate 320 17.9
8.94 10.9
PRESSURE drop an sizin dat for venturis-Fig EN
0.63
f3
f3
id
0364 0.44
"In, of wate
CHEM CA
it
0.51 0.63
Typica Manomete Ranges for Venturi Meters
..fhw
it
ly
eva
0.35 0.45 0.5710.69 0.75
ld
en
io it ratio,
ld
Ratio an Capacity Constants (3 C, F9 Commercia Venturi Meters
Averag value, ( 3 , =
ta
pipe configuration. Upstream straight-run requirements in ti
Dall flow tube 90
Ratio,
ll
1975
io
ca abov
th grade.
lu et
e,
co nections in addition to th pres ure- ensi
ta s.
ll '63
'" High-pressure __ connection" , li lt " ' " ""Flow irecti
".
Pip wal
Q)
+-'
Q)
J.
J.
-- On
or Tw Elbows in Same Plan
::0 Q)
.9
io""""
·6
.~
,... """"
..,...
::l
J"
Static pressure "./hole
'0
--
-1
rltL.----
\1Ur---
L~wpre.ssure--4il-
4~~-+--~+-~~~~ 2~~-+--~~-r.~~T-~-+--~+--i
O~~~--~~~~--'_~~--~~-J 0.2
B.
0.3
Ref: [2
Re
UPSTREAM straight-run
op ning
ilot
nd valv
Pito Tube
b. Double·Venturi Pito Tube
21
fo ventur meters-Fig
should be
cessible
th pipe in pito tube must be precisel lo te an av ag velo it maxi um ve ocit poin an orie te in th di ec wpa
ubes
if
me su emen
ue to thes cond tion
must provid ir
difler ntia pr ssur
onventiona
pito tube Fig. 5)
Be ause of th sing e, sm ll im ac hole th pito tube 164
ga lines) xc llen or me su in high velo ities, av hrgh·c pa it
flow having VCf) ng nd easy
smal ventur is added. Th double-venturi
IiIfflmgeilien'
MARCH 3, 1il75/CHEMICAI.. E N G I N E E R I N G
I l i l l lU l U l U l I l i u m l l U l l I l I lU l W t m t l U l l I I l l I I J Il U J J I I U l l l l l l J U l I l l l l U u u u n U U l I l I l Il I l l l l1 I J I U I I I I I I I U l l i H I l I I IH l H l l l l l l I I I I II I I I l l I I I I U l I I I U I I I I I I Il I i I l I I I W I U l I I J l ! I I I J I U l l I l J l lU I I I I I I I 1 I 1 1 J U I I I J l l I U I I I I H I I I I IU I l l I l I l f I l I I l I lI J I I I I I I l I l J I I I U l l l U l l l f l l l l l l f l I l I l fH I I I I I I I I I J ! U U U U I I I I I I I I I I I I I I I! l 1 1 l 1 1 l l 1 1 l m l l u / u / U I I I
aigh
engt
Requiremen
fo An ubar Flow Elemen s- able Upstream of Flow Elemen Without Straightening
Vane In Pipeline
With ASME Straightening as Las Approach-Turn), Pipe Dia.
Pipe
Configurations
in sa
Pipe Dia.
Di
Downstream of Flow Element, Pipe Dia.
:3
plan ow
wo planes Redu,cer or increaser Fully-open gate or ball valv Partially-open valves Glob valv Note Contro valves should be locate
afte flow element.
1111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111 1111111111111111"11111111111111111111111111111111111111111111 11111
ential et ee
th high-pre sure impact hole an
anom te
ef ec ions or
ro th an factur rs 2C ity coefficient ub
av be
Fo ro
eliminat
impact hole (h h- re sure four
ac
le
itot
Th
he
he fl
le
nt ca be nstalled deep be
ra
ith-
be an itot-ven for orific de es
at s,
ca ac
th n'r a eragin
it
ide) facing th fl do ns ream
ub
tu
direc-
(low-pre
w.
1,200° [3]. Form as fo izin nn bars ar imilar he rifice form la an fact re [3 pr ides ca ac ty co efficien as (K/,v)' wh~re Kg ge etrica cons an F; is velocity distri tion fa tor, Fo rans tional an otal turbulen flow F; )' 0.82 Th capacity coefficient, is analogous C. to th orific capacity constant ipelines wher turbulen fl xist change pipe size of th metering sectio is rarely necessary-s-an
PiP'7nlmF!tF!r ing taps"
Static pressure ta
-, '\
<,
Flow .U
Throat insert
Recrossed\ pressure nozzle Do~nstream
ANNUBA
tube
mete is an averagin
CHEMICAL ENGINEERING/MARC
pito tube..,...Fig. 3, 1975
MP
ub
handle flow in either direct on-F g. 165
then only fo extremel
lo
or extremel
hi
fl wrates
selected Permanen
pressure loss is negligible at Th foll wi able list om representative va ue fo variou pipe sizes:
No minal, In
Lo s s ,
(Kl,')
0.82
h",
.6 to 0.62 0.66 to 0_ to 0.75 to 0.78
to lY
1% to
to to
to to
<%
Instrument deflection at flowin conditions fo liquids:
Fo instrume
ca ibra io
at
stan ar
Noting position of float-head edge
(6)
in
h w = - [ 0 . 1 7 6 Q v 's / (K ' ! " v) d i) 2 ,
referred to capacity scal on glas tube give flowrate readin
liquid-flow S) Instrument deflection at flowin conditions fo vapors an gases: (0.002 78 W/(KuFv)di
hw
ifferent al pres ur t::.P
Straight-lengt
ob aine
60
P ]2 ,
...... .. Metering float
(7)
from
I nl e f l a t s t
0 _ 0 3 6 1 h w ; ps
(8)
requirements fo 'pipin design as rec-
-Inlet
connection
Ref: [5
Th flow-sensing tu (F~g.7) co si ts of shor ho sng ec ion, an symmetrica an tapere hroa sect on avin flow re tric io in he ce ter. Th throat sect on er
am ra
re
en
ti
tays co stant. In co tras
constant-restric io
an th pressure difference across th restrictio prop rt onal to flow Th ro ameter cons st of apered eterin
e.
es
e-
become ub wi
ca C(2gh)1I2. Exac formulas fo sizing this impact tube
re Appl cati ns fo th impact fl
tu
ra ge from wi ce
Straight-lengt requirements fo this device are; pipe diameter up trea 0diameter pstrea afte throt-
Rotameters
Inro ameter he area restrict on varies prop rt on to flowrate an th pressure difference across th restric16
re libriu
when th pressure difference across th float, plus an
In ai an wa er er ice, th viscosit effect of he 1u on th rota eter re ai ractical cons an Th ma es poss bl he us of standard capacity able fo such flow treams Standard sizing char s, tables correc io facor fo an fluid, ta le correction fact rs fo pres ur an temperature, selectio guides fo type of rotameters etc. ar availabl in manufacturers' literature [5]. Hence, rota eter ca cu ations ar eldo ma pr ce en ineers. cr Rota eter er
ar
especially suitable fo vi cous iq id wr
it
t}
lt
ti
P ip o
PIPING
arrangements fo installing
rotamete having alternativ
-[g~ ti
C o nf ig ur at io n
taps ar simple an economical-Fig
co em
a pe ,
rr er a br a
ew ca ibrate
S uc h an ac
to show (a fl id elocit
an
at
(b percen ag
con-
at fe er racy Straight length of piping is no required Dependin ip co figuration an rotame er design al erna iv .t provid simple an economical piping..arrangements ro er ck In cl an rm ro ameters, by as gl be alve no necessar Locate th flow-regulatin glob valv to th rotamete (a before e te r rv
houl be access bl an th operatin aisle. ex et %of rotameter. Rota eter calibrat on av ifferentia ranges
th rotamete
scal visi le from
as
fl fl
es
th
itti
ar usua ly nonadjus able an 0-50 0-10 0-150, -200 an
th flow signal
contro valves
References 1. Engineerin
ROTAMETER-ORIFICE
168
measures larg flowrates-Fig.
10
Informatio on Ventur Mete Tubes, BI Div. Ne York A i B ra k C o. , P ro v d en ce , R I 2. Instructions fo Pitot-Ventur Flow Element, Taylor Instrument Cos. Rochester, NY 3. "Technical Manual-Annubar,"ETliot1nstrumen Div. Dietric Stand80302. r. l o T ub e D i . , B et hl eh em , P A 1 8 0 1 6 . 5 . " Va ri a l e A te a l o e te r a nd bo o , " V ol . I -I II , F is c e r Porter Co., Warminster PA 189.74.
ControlValves
rmulas
nd
stalla io
rocedure
fo se ec in
ROBERT KERN Hoffmann
an usin
La Roch
ontr
valves or luids.
Inc.
tr proces operatio
handling flui streams. Hence, we must il it en is to meet proces conditions an to ensure proper installation th
ti lo lu valves enerally contro valves it rotating axes ar suitable fora wide rang of flow-control applications
Ch ra teri tics ls
tr
On majo grou of contro
co
ported Flow-control characteristic
al es esembles th
lobe
thei flow characteristic Quic
in
lv
Valv Pl gs
ir
pening
depend on th shap
are: single disk (for high tempera-
at linear flow characteri tics an shor te movement inea Flow-A plug ha linear flow characteristic th lift Equa
ercentage-
lt ur acro an orific othe flow-sen in element. Th single-porte contro valv (Fig 1)find us wher io to lo
capacity valv than th single seated ne of th same ize. th seated valv cannot shut of tightly. Th valv accessories, an
conditions
To meet your author se Chem. eng., Dec. 23 1974 p. 66.
CHEMICAL ENGINEERING/APRIL 14,197
twee
thos descri ed
pl
as equal- ercentag io t-
an facturer
provid
diagrams
'A lu having linear-flo characte istics is commonly specifie fo liquid-level control. Th equal-pe ce ta ll 85
Single-Sea contoure
Double-Sea (Equal-percentage ported plug fail open)'
(Equal-percentage plug fail closed
va
fl
available; or wher
ressur drop acro c-
(als
called
sp
-F
th contro valv te is ic
ce ta
control. Actuator
Alternative Actuator an Plug
perators
Butterfly Valve
te is cs
al
positioner
valves av th actuator side mounte ecause es ax e. ct in th in ac valv axle Th valv housin .and th operator's yoke ar ll
th actu ti
Bal Valve
separate at
Camfle
Valv
available. Safet
Requirement ROTARY actuator moves flap plug
valv ca be in cl sedo 86
or
open position Thes alternativ APRI 14 1975/CHEMICA
is
ENGINEERIN
Lubricator fo valve-stem packin bo
Finned Bonnet (For temperatures higher than 40
Bellows Bonnet (Sea betwee valv an packin bo in toxi service)
Extensio Bonne (Fo cryogeni temperatures F)
Sid Mounted
Cas Mounted
Pneumati Positioner (Or transmitted.
ACCESSORIE
ex en
(F
im to (Restricts stem movement
usefulness of contro valves by prov ding fo extrem
po it on ar acco plis ed by reversin at
an
Handwheels ma al pe atio at startu or ai failure)
unusua conditions-F g.
th seat ring an orderly. shutdown procedures
On concer of he esigne is to se ec alve that wi fail-saf in th even of nstrumen -a fail re In princi le contro valv fail af if te perature an pres ur valv become inactive Fo example, fuel-oil co trol valves heater urners fa (i most cases) shou fa open to av id verheating he ee co ro cl ed ea boi er fa ls cl sed. Refl x-drum va or outlet an reflux pu ch at compressor bypass lines, an reciprocating-machin by pa li es fa open an usuall th feed-control valv fail closed Generally, designer of flow system should consul process, instru CHEMICAL ENGINEERING/APRIL 14,1975
Capacity Coefficients of Valves Valv flow coef icie t, C" dime si ns of th alve an th smoo hnes es Manufacturer
give th followin
c,
Q(
of urfaces. ai
definition
VSivlJ»
6P::::::
Capaci
in exes fo th
ut erfl
va ve ar also give
CE REFRESHE •••
Nomenclature
c,
fT
C"
position
," D/d Expansio
factor
M ol ec ul a
e ig h
Absolute
pressure
"so/p
ia
t:..P
r,
i f e re n i a
psia
p re s u re ,
ps
psia
reducers
p/ Sao
v,
Absolute temperature, S o i c v el oc it y f t/ s iscosity
LO
hara teri ti
of orte
or cont ur
cp
60°F lb/ft" 60°F 62.3 Ib/ft
P6 Ps
lu -Fig
PSOw
60°F
Subscripts
Upstream condition
Control-valv
coefficients for single and double-seate
Do nstrea
conditio
.
Calculate Flo Coefficient, Cve-When sizing contro valves flowcoefficient is calculated with normal design io te in gp om
c;
Q(
VS;y"M)
downstream pressure,
av ta io
an be susp ted.
exceeds C v e . flo
betwee
coefficient, or: Cv/C
I'
he brasiv flui is pres nt Critical Flo Factor C, he pressu
vaporizati ca be onsi er ro conditio di mete of th do nstrea he riteri
where: gr di nt
ro
onside ubcritical th va or pressu of th iqui il no ge ighe ha th lo st pr ssur poin ac os th ontrol va ve po pres ur is he pr ssur temperature. Tables of thermodynami properties of liquids give corr spondi satu ted-liqu ressur an temperatures.)
or subc it ca an
the
he va ve or this ip il usua ly
it ca
lo
in iquids
t:..P
C/(t:..P.)
(I)
s»
q( t:..P.)
(2)
s»
(3)
VP1/Pc)P.
and P, is th itic ressur psia I Fo simplicity t.P prov de O.5P he sizi ormu fo itic flow is
th
"c
article.
trifug 88
and
0.5 to 0.8
C v c / C ratios bu th plug willl:>~closer to th full open or ul lose po itio nder hese onditions, we lo he mportant ad an ag limit operabilit of th process.
or
upstream an downstream pressures,
pump Critic
lo
occu ac os
pressure-
A P R I L 14, 1975/CHEMICAL ENGINEERING
IIII11HunlmUlIllIIlI!l1!UllllllUlmnUUlIIUlllllmumnllUlIIlIIUlIUlIlIlIIlIIlIUlIlIlIlIlIUllIlIlIIlJII11111111111111111111111111111111111111111 11111111111
lo
lo iz
Single-Seat"
efficien
il as ic reache th soni velocity
C"
Double-Seat"
v.
.0/. 12
9. 1%
nois an
it ft/~.
68Vk(~'/p),
(5)
vibration.
are respectively:
1%
/:'P
11
75
ti
0.5C,zPl
(6)
O.sqP
(7)
av id C, value.
45
Th critical flow factor 1,160 1,620 2,000 16 Thes values have been obtained fo Masoneilan 10.000-serie (eithe equal-percentage or V-port plug valves having full-capacit trim bu also appl to simila valves of othe manufacturer [2]. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
is
dimensionles
number
C,
betwee
th control-valv
coefficien unde 'critica con-
facturers literature. V a l B et w e P ip e R ed uc e s -F lo w
it
correctio factor, R. In critical flow th correction factor is Crr, whic replaces lc io rr size. r1 rr and av values smalle than Numerical es th in li te in Letus ariz la in contro valves fo liquid an ga services unde di ferent flow conditions [1].
Liquid Servic S ub c i t c a
F lo w - Fo r
coefficien is: (8)
if
position,
it
replaces /:'P(min)
ar P: PI
ve
(Q/C )2S,
psi
(9) ",
plug position betwee expression is I::.P
where CvclCv
0. to 0.8,.a convenient
Cvc/C
(CvclCv)C
ta
S,psi
ct
(10)
at ).
la
ci
am
is
flow is (II)
Cr ca CHEM CA
ENGINEER NG/APR
14 1975
F lo w -I f 89
U l l I I lJ l l I I l ! ! l m ! l! I r 1 l 1 l1 1 U l l l n l l m l l l l f l l / l lU l m : U l I l I Il l I lI l I I l !l l I lI l n l lI l I l lI l I l U I I I I I I I J I I I I I 1 I I 1 1 I I 1 I ! I I I I I I I I I I I I I I I I I I I I I I I I I I U I I I I I I I I I I I I I I U J I U U I I I I I I I I I I I I I I I I I I I I I I I I U I I I I I I I I I I I I I I I I I I I I I I I I I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 , , 1 1
l-
r . .
lv
lo
fi
li
le Double-Seat*
ingle-Seat* Condition C ri ti ca l
V-Port
f lo w
1 _
C ri ti ca l
c;
f lo w
nt
be
r -
(d
S ub cr it i a l
0.98
C{
f lo w
V-Port
0.98
or 0.85*
0.94
0.86
0.86
0.94
0.96 0.94
1.5
=:::
Equal-Percentage
Old
pipe reducers ._._-_.Thes values have been obtained fo Masoneilan 10,OOO-serie plug valves having tull-capactt a ct o f o f lo w t o o pe n ' Fa ct o
trim bu also appl to simila valves of othe manufacturer
[2].
f o f lo w t o c lo se .
1 1 1 1 I 1 1 I I1 I I 1 I I1 I 1 I 1 I 1 I I1 I I 1 I 1 I I 1 I1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 ! 1 I 1 I1 I 1 I I1 I I 1 I I1 I I 1 I1 I I 1 I 1 I 1 I1 I 1 1 I I 1 I 1 I I1 I I 1 I1 I 1 I 1 I1 I I 1 I 1 I 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ' " 1 1 1 1 1 1
size th simpli ie becomes:
calculated control-valv
c.;
i\
(QIC,)(
coefficien
.re tl
(i.e.,
condition:
P,,)
provided P , , : 2 0.51'1'.
Th calculated control-valv flow il be ::':;
where ::"P or critical flow
coefficien fo subcritica
11.65y3P(P
provided th.a t::,p he ,p O. C/p 1O.13C,P1
If th valv is locate
betwee (IIR2).
lv el ithi
to th or pi
wo
ize.
ls
Computation
n.sc/p!.
LI
b/
(14)
educers, multiply
Replace
(14).
cien ratio CveIC.,
Let 1 13 ,0 0
V;;; pi
llustrate
(13)
P2)Pl
c, with
fT
in
iv 0. to 0.8. Th operatin
it lv in sizing valves fo critical flow ma
hase Flow
it
c;
44.8
y'Xl>(=(.]=+=(=.z==)-
where PI and th 'phase densities respectively tu 90
(16)
O.SC/P (For calculatin t::,p th de sities in two-phase. flow ee Pa of this series Chem Eng. ec 23 1974, pp 60-61. Exampl
----.~--==
ve
63.3 ~l'fJ]
I!C
ic
pc
io
1'1)'
(15)
),
te 14
75
CE REFRESHER•. I U l m l l J l U l U l U l U l J \ l l l I I l I l I U ! I I l l I l l I Im l l l l l l l l l l l l m m m l l l l l l l l l l l l l l l l l l l l m l l l l l l l l l l U l i l i l U 1 l l 1 I 1 1 1 1 1 1 1 l l l l l l l l l l l l lU l l U I I I I I l I I I I ! l l i U l U I I I I I I I I U I I I I I I I I I I I U l l l l l U I I l I I I I I I U I I I I I I I I I I I I I I I I I I I I II I I I I I I I I J I I I I I 1 1 I 1 U I I I l I U l I I I I ' I I I I I 1 1 I 1 I 1 I 1 I 1 I f I l I l l I I l l II l l I l U I I I I I I I I I U l I I I I I I I I I I I I J I I I I I I I I I I J I I I I lI W l I l I l I l I l I l ! U U l U l l U l l l I l l I
li
Ii
'" :i: ..
No 1046 Bronze Glob
Valves (Threaded)
Stee Glob Valves (Flanged
Flow Coefficient, Flow Coefficient, Flow Coefficient,
Fo Valves No 546P-150 Ps
For Valves No 556-20 Ps No 576-30 Ps
0P
Size, In
Fo Valv No 1040-150 Ps
Flow Coefficient, Fo Valve No 1042-300 Ps No 1046-600 Ps
46
55
200
235
2~
29.5
24.
1~
400
41 Note Flow coefficients have been obtained fo valves manufactured by Jenkin Bros.• bu also appl to simila valves of othe manufacturers. 11111111111111111111111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111lIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII IIIIIlimllllllllllllllllllllllllllllllllllllllllllllllllllllllllllili11111111111 11111111111111111111111111111111111111111111111111111111111111111111111111111111 111111111111111111111111111111111111111111111111
-f
estimates, will have mino effect on valv capacity Thes ar smal values=-square-roo function of th calculated w c Wh ritica lo occurs in th liquid th piping fter nt ol ve ou be ul sized. Vapori atio in re se pipe resistance consider bl To stay ithi easonabl velo itie when vapo iza-
he up
pi me
of
he
ve
hi
or la ge pr ssur op os vertically up}Vard.A control valve will operate in angular hori onta or vertically downward position Neithe pipin designer no operator ccep th se positions. arge angl -control valves re an exception; hori onta posi
ypaS in
on
bypass is usuall on
lv
provided fo contro valves sm ller ng
ve
s,
single ontrol valv withou bloc valves an bypass is usuall sufficient in clean-flui service; or wher paralle equipmen ontainin ontrol valves is installe it
oi or soli particle
reducing stea on on 92
contro
ou
ut
qu
valves with th flow coefficients fo double-seate
va ve ob va ve or nu ll oper te th ottlin valves in th same ay contro valves provid that flow coeffici nt ar av ilable
o w v ap o
of qu st no he ng ne At high pr ssures high temperatures nt he nt ol va ul
.fo om on uf be ve se of va ious seat ana-plug designs, valv coef icient ar no s am e mp be va ve de by nt manufacturers.
an be oc asionall
expe ted,
tempo-
service. ng va ve
n, st
ow ow
nt
operators. Most piping specifications call fo contro valv APRI 14 1975/CHEMICA
to be
ENGINEERIN
~ ~ > < ]T c k G )
_d"l
'"
~r
. . , " '; = . " . " . . . _ "- " . , ., . , " ", " "
. . ". -,....,,7"1
:;
'0~?
MANIFOLD
an bypasses fo installing contro valves into th proces piping requir
tion syst m.
proper clearances an drains-Fig
ensing points or lo
pressu
temp ra
connec thes elements Ai line ru from th transmitte or npla
qu rement
maintenanc
ar show
lear nc
in ig 7.
spac is requir
im nsions of contro
.the, instrument-air header Leve controller usuall have gage-glass companions It gl sses from he ontrol valv mani ol he op at ng
than
prov economical Typica standard manifold ar show [10]. outlet lo approa th ontrol va ve om an leva io
ve se
he looped bypass type erve ho izonta
lo
structural columns.
On drai poin isrequired if th ai
losed. In satu ted-st
trol-valv manifold. he utom ti ontrol va ve
ontrol valv lo
pa
ails open
on or tw st am
of an inst um nta-
sizing pump-suction piping
References 1. "Handboo fo Contro Valv Sizing," Masoneilan International, Inc. Norwood, MA 02062. 2. Dimensions-Masoneila Contro Valves an Auxiliar Equipment, Masoneilan International, Inc. Norwood, MA 02062. 3 . " Va lv e i zi ng , a ta lo g 1 0 i sh e o n r ol s o . a r h al lt o n , I A 50158. 4 . i sh e o nt ro l a lv e i me n i on s u l e ti n 1 -1 00 , F i h e C on tr o Co., Marshalltown IA 50158. 5. Boger, H.·W., Recent Trends in Sizing Contro Valves 23rd Annual S ym po si u o n I n t ru me nt at io n f o t h P r c e I n u st ri e e xa s A& niversity, Colleg Station, TX 77843, 1968 6 . B au ma nn , h e n tr od uc ti o r i i ca l F lo w a ct o o r a lv e Sizing,ISA (Instr Soc. Am.) Trans. Apr. 1963 7 . a um an n . , f fe c o f P ip e e du ce r o n a lv e a pa ci ty , IllS/I'. Control Systems, Dec. 1967 Instr.
Contro Systems, a n 1 97 0 9. Boger; H. W. Flow Characteristic fo Contro Valv Installations, S A I n t r S oc . m ) 1., Oct. 1966 10. Hutchison, J. W. (Ed.), "ISA Handbook of Contro Valves,', ' Instru ment Soc. of America, Pittsburgh 1971 93
Su ce sful operatio
of pump
characteristics. Reduce
suction.
Example. Fig.
potentia
conhave be '-
bert
se ec ed
Available rn
2:
and
8)
9) fo NPSH Lines
50 It
raw- ff nozzle
izing.
45
and
f f ff f ff in f f i f f i : f : n : m : n 7 i ff E f f i
lJ~--I~
t-J:j:ffiti=~~~~-::j
K=O.78
h.i.
/2g. 3K .V2/ (2g) Where (0.408) Q/d sistance coefficien K, 1. hL
1.
vi
Fig I- Graph
for estimati
draw of
nozzle sizes
hi.
'v==:':
2.
EXAMPLE:
-.
:~~::~:;:::::G um
__L_
-n us
b e p :n : a b
he
amoun
Flow rate
2200gpm, hr th
Pipe size:
v'O.4D8 Q/v 11 in.
Nomina size
Fig 2-Suction pip
15in. 7.4 [t./sce ' O. 4
.4
12in.
co nections
to .elevated draw-off nozzles.
iA3i.E2-r 1F' ~-a celc leticns form with th lOr;: [;::91.3 Subcooled Liquid
Saturated
3.
4. S ta ti c
(a b)
h ea d
ine 5. L(+
p re ss ur e
(c
8.
6'
Line
~V/~'
at
10.
oess
Line
·_~psi
p re ss ur e
ti
no le
~~;i~;~~)
R eq ui re d
at
tota
of suctio
pipe re istanc wn Fig-
Flow Data: iq id pu ped: Heav as-oil Fl rat at te perature 00 pm pecific gravity: 0,88 Density: lb .r ft Viscosity: .6 \1 inim liquid leve in ctio dr i. With ht. 18inc th velo it fr ctio
\10.40 (900)/8 6.78 inc pipe ad iz
ni Fricti Lo Reynolds Number: Re
Lo
ti
10
ampl
18 in 1, II
ft./sec
800 in.,
Fig. 4-Manufac urer's
dule 40
NPSHdiag am
·s should includ
yn ld
(900 /32,380)
and ps
40
Total:
at ospheric nd flow th pressure
an
(a)
,-
45
gate valv (open) strainer: reduce (6-in.
tati
L in e
by
20"":
Equivalent
Line lengt elb ws 3(22)
Eq ival nt
fo
50.6 (Q/d) (p/I') 50.6 (900/8 (55/0.6) 522,000 Moody's! diagra at this
fricti fa to fr Number, 0.016 AP100 (8-in.) 1.35fS(Q2/d 1.35 (0.016 (0.8 0.47 psi/10 ft
Lin
= ( 3 , 5 '5 )1 /1 4
.fJ'7
\10.408 Q/
nozzle iz
No inal nozzle an 32,38 in.
Suction
al
pipi g. (d
ti
p)/144
.\1.
i s n e ga ti ve .
PUMPV1
E-
N PS H
SUC!IO R.F. ( f t . head
co figu atio
ps ft
.lQ§_)
NP
12"·/· Fig. 3-Exampl
15
P_S~
ai
YM 6 -
ps
_ _
A va il ab l
~STRAINER
49
ps
Line
6. 7.
180/100 ad lo
acuufi-l
0.475
0.855
(144 psi)/p (144 0.855)/55 .2 ft
re ures
line.
or subc oled-liq id
Piping-9). Pressure-S Pressure Drop-S Pumps-4, Resistance-S Size-7 Sizing-B Suction-S, V np o P re ss u re -S ,
~-
Iping Intera ti ns betw
n" ydra li
requir
nt
an
piping
nfig rati ns
naf
il ar ty it ap ip ng ig is an tial requir nt fo th de igne ydra li yste Th accuracy-of is calculati ns predictions flowrat and pre re differentialc.reiiabiliry f_ peration, and th cono ycapitai, nergy,~aintenanc an peratin ts pend to gr at tent pipe nfig ra ti ns an pipe co ponent In th article we av recogniz d. th importanc raphic ipin nd to imit re av pr nt it fundam ntal We will now. valuat th fl yste nd piping ig is illati ln, isa re in rate it th th in id al yste discu in arlie article
Layo ro
fo di tillatio fl
a.'t pi
is il at
rac .'
levation. Th p-
ti
th
in
ip
ir
ti al run,
ip an towe nozzle belo
fr
with ab
l-
am
line
lo
th
re
pipe rack
levatio is
an al
ne
ld
fo th
be arrang
lin this le
ts ip line roppin atio ll appr
ip ra
by
ro ip
li
bank boil
is
le ti te
is al in
fo ally
team ne to
(F/ 1)
th
inth actua. plant. nd pl awirig fo th prin ipal leIil. nt ally integrat intoa.
acce aisle at installations). Each IIlanh le platformforIilaint nanc~. alve an in tr Fnts locate above th platform fo c6nv nient:atc Fo no y'a.nd asy·.s pp rt piping ld
ti in
leav
.the
11). lo at ad ac nt to ac in Fll, fi le ti lu n. di tillatio lu ar
le
colu ns
ia ra
li
it lf as ific
itable lo ti ri nta. t'
the towersh0\oVsthe segment 1s f.it ir ferenc allott dt .•piping no zl ,ma.n: th le ,platf rm ra nd la patt rn ~'llfl llyl ad t? a·.w -organiz I
.".: q~alplatforIil7~r~ck tspacing and'tJ J.eorientati0Ilo br
th
r~ ar iJ il tw tf ad rs id th ll le ne pp a: in
atid -
..
. '
\
()Jl.b th th pi ra ' : : i . ' . ; '/ ; " - . " .
~!;;! ~: ,.
(.,:~:::?:::-~;
Overhead lin
,I
,. Line with both ends higher ineswith ne en
Distillation column
elow
rack on either pipe rac elevation _L sw hb ends lower than e r
Condenser
-Access to pump Grade
Reflux pum valv _/
...Alternat suction line
suction'
b. Elevation Steam
Pip rack'
-·-Downcomer
a..- Process flow.diagram :,-.. -',,-
t_
.
-,~-
_.
ca turn left right, depending the-plant's overall arrangement. di tillatio lu n, th larg line ar th verh ad vap line and th reboile downc and return. Thes line sh ld ave the.simple and st direct configurations,to inimizepress relossand cost: ring normal peration, th pu in Fig, tran ports liquid at quilibriu This ans that th distillati n.colu and reflu dru are levat d'to atisfy c. NP H(n tpo iti~ ctio ad) require nts Th discharg linesofte have two destinations..Total-head requirementssho ld be designedand calculated sothat, perating points fall th pu p's head-capacity curve wh pu ping to an alternativ de tination. Alterna-, ti di ar linesca av qual apacit an alternative peration, partial capacity wit im ltane peration. All alternatives..sh ld be. investigatedf()l".
-,.
,;
_.
_.--,
thro gh towe nozzles,and extending acrossthe towe .. dia ter. Reboilers wit all at dutie are ally designe as helical coils
Reboilerarrangement~.
In ri ntal th yp reboil rs liquid fl fro an levated dru .· r·towe botto .oJ: towertrapo t,bo thro gh dO,W'nc eripe.tOit~ebotto exchangershell. Th liquid iSheated,.leaves'th re ,.,> Th de ign fo ~pu pe rebo~lercirc it is ilar..;·boil th returnpipingas ap r';liq id. ni ture totll(1t refluxpUInpsyste Ab tto pu trans-. and floW's,backi: th .tower()r drum.. port th liquid thro ;: Ilger' fire at In vertical reboil ts at lg ally th an.clreturnsit to th distillatio colu n; Closeattenti0n.; shellsid.e.Inh rizontal reboilers,beating is th tube 90% ··.··.shCl~ldheaid to.possible.two-phase.fl9W'i n pipeline id Fora larg vaporati rate (f re pl .._ '.co ing aft ,th ater- peciallyw we~~tt9; totalfl.,?",),a k: ttl tYP9.r boiler, sed.;;/;'; '.i. "'locate the.heater:clo etoth ~olurnn~..•.. Pii>ingto horizontahrebOilers'is de$iS'll9d:~s '..: In rt d-type reboil rs av n, pr ·pipin ~· and' dire tly: 3.$.po iblew~thin th litnitatipns .· 'L r-diam te tow9rs.can av pn to fo rU-t b, th rmal.. pansion.forc ........ "\........ .:'stil.bb,llndle ins rt~~',?Jrectly'int t~Jiq i4.~pace .S rn1lWtricalr rang ntsbetw n.th .dJ;aW'off ;~i': ' _ " ; - ; : \ / ~ ' 2 : ~
il tl
inle no le as an return conn ti
nons pt
.~~
ic
piping nf re-e no ical
fo bo le
as be we th rebo le th tower, ar pr ferr
ft
av
trical piping an atte pt th
re istanc thro re re istanc in in th th r. Henc in bo leran nozzle
atio
ay ls be ac re-fle ible piping
tl
an
ld be
tw ad
pa alle
to qualiz
both le th reboil piping ne le pr duce alle fl than neve at di trib ti will nt il be
gravity-fl
bypa
is
Maximum liquid level'
ally pr vide
Steam condensate
a. Bottom of reboiler should be elevated just abov to of condensat pot --Distillatio
fr
column
comer. alve ar
rarely in lude
in re
il
piping
pt
th bo ar an pe at at an wide at-capacit rang co pani requir line blinds to blan ff th towe no le ring td wn turnar nd an aint nanc conn ct to th tube id
rizontal reboil rs Th
quir reboiler'
ar an
Reboile
tube id
no al inl t.
ad
inle
ar 1:
elevations
bo nt line le at ns ab ab nd leve fo changers ab at gr~d provid cono ical arrangements=-valves.arid nv ie t, an aint nanc as ar an nt th tati ad ar well determin betw th xc an r' nt rlin an th draw ff and.return nozle ti al re il an al pport th di tillatio lu it lf reboil rs po lo at aftert lr
as what
th ig
av
nd nsat or.Iiquid-holding tube id tl t,as wn inF-
nt rl ne le at an nits at
F! trap to th nd ns po than th bottom th xc ange ng be th nd nsat an th xc anger' at-transfe duty nd nsat le l.in th reboil rang eat-transfe control. in th pr is relati ns ip '>and:thevertical ..condensate-c
th no
reboiler av
ld no behi ll to av id floods' ad affecting'
r,to pr vide fo awid Pc.fPce sonditions.deterbetw th an ntrol·p()t· rf't,niiif'Y"
h:o.
UH<:;Ul<:;l;'V.Jl
centrifugal
th le~e inth
xc an
r. Th
H:'VdUlJ,1
dirrerence tOlm~:n7:'
Required elevation difference betwee liquidJevel in tower and exchanger
th Ut
th R e e re nc e
l in e
tl;
3.5 to 5.5 ft
0:
a. Horizonta
Liquid density in downcomer P2' Liquid-vapo mixtur densit in rise Pl
P3:(Pl+P2)/2,
Averagedensity in vertical reboiler
Horizontal
io H1in F/3) pr vide th po itiv -stati ad fo flo in the reboiler circuit, and verco esfrictio losses in th xc anger, an down an return line •.
Designin
th
icaUyin F/4. am at th tower'
il
tl
yste
an
return no zl
ir
referenceline.and isbackpressure in the riser'svaporliquid colu n; th pressuredifference (tli'=P .m st verco the exchange and piping frictio losses ,!Th refore 1m be gr at than 1i th /144= liquid densityin th down r, th ,can tw alte nati
.;.' '>
.,.c..
1.
rizontal
'lahtioni~,.forced' by the static-head differen.cebetweti~.·.·r:,.,.".,'.,·.,.'".",.,,'.,. t, .· liquid colu in th riser Fo convenieri:ce,referenc~wher lin are ch at th xc ang r's centerline fo J:i~ 'zontaLreboilers and at th botto tube ee forverti~i: calreboilers.'Xi< .~_", If-,::_ft·""iS:,Jiquid, t he ' " -d .o w n co m e r a t : . - ~ . ~ , t h ~ ~ : : , > ':,.,.
an
rs (s
rtical
an
(pzH where
th
P3H3)/144,
ai
ra
it
F/4b and F/4d):
rs (s
ix
ity,
iq id an
re
iq id-v
ixtu
in
4,000 3,000
(4)
2,000
reboiler:
Eq (4 provide cons rvative timate ra ient in rtical reboil rs tual nsit q..
1,500
th density il be le
'"
th vertical reboil ld be Ho ded. axim levati th to tube ld no be ig than th in liqu le th
Hydrauli
in
ri
1,000
800
.Q
'-$'
600 400 300
.u
ntal reboil rs ,.
In th following di cu ion, th ydraulic conditi ns nl in rizontal an rs il be de loped. (T derivati ns ar th am fo vertical exchangers.zexcept that will replace riz ntal xc ang rs :) Fo
I If
af ty fa to re diff renc
pr
(5
AP isintr fo fricti
lo
th th availabl is alved, and:
(6) quantity (H ly ni ri in fo 3 / 8 8 )P l .OIP is always availabl exchangers
14a).
Th
in at:' horizontal
depends im le ivin fo th le ti iffere th ra le xchange centerlin (di nsio ap rati taking plac in th reboil r. le ting th vapor-c lu backpre re in th return lin ,th ax im able ri in forc is (7) ap li atio th belo this axim
th
tower. Fo th
APmaz
al
iv ng fo
is
lu to ally larg
Frictio
an
inac
ll av ilab than al late
lo
ra
isw
pe iz pipe ia ters
re
r-
,,
in reboilers
to al fric io lo l- rc la in boil yste be alle than th availabl drivin by fricti forc Th pre re lo ca ta plac in tw ai lo ations in th an it lf ,and in th
piping
.\
Hence:
APp
values':
0.02Pl
Shaded part of char establish'e size of downcomer.
Frictio as ,O
lo
in reboilers, A P e ' ar nerall ps (A note ld indicate .w
.
to 0 . 0 8 P l
.
ractions
iv th
'1 . 100 t.
Chern.Eng., Jan. 6,1975
'I
. ·••. 12
ft, and APma
50,lb/ft 1 2 8 8 )5 0
impl relati ns orationnite is
ps ar
.1 2.0 PSi;~ia~dl:e~:~B~l~~~:~~~!::r~~~~:~~!~P;:~:
th
ap
.. ,e Fi
av
1' .... di rPl::rralt_. n)d' erro '.ca·.·· .•l··.c·u· la· ..• ···I:o.ns,. ·...ec .···t··
e . is pr le
tha. .1,P.m J:
'altlPmdzk.as oat
APmaz'
However,even
nt
1.·.. ..•..
in F/5'T is'\
....
evaporation. >p
if
'a
...•.. jt.•.....
"<.11;
nd In vertical reboil nd forc an be rate ar ig turn line is
circ it re an
il
lo
ar
le atio
th
in
HI>
le ation, at
th
nc
(6), where
Q, from:
fl wrat
5,000/500(36.7/62.37)
with
rawoff no le
late volu
Q= W/500S
gr at r,
d. In ttle-typ reboil rs vaporati Fo th reboil rs larg -dia te ally nece ary.
we al
imilar co putati ns
28 gp
fo th
ri r-re
bering
reboil line putati ns fo ch in wh th th line iz ar ad quat requir nsid rabl detail ld al note that th boil as wo inlets an F/
3, ft: (9
3P
PI wn replaces .P co r, ri an
P2
no le anno xc ange
I::!.p
I::!.p
I.
be lowe than
requir th
nt
I :: !. P d + I : :! .P r
re
ally il r'
au
inim
I::!.Pe
th
pr
ve
levati n.
nstrate
an
th
is in reas
th
Viscosity, Molecula
(hot)" p, Jb/ft3 }L, cp weight,M
ti n,
al
85,000 36.7 0.6
Liquid
Vapor
59,500 36 0.5
'25,500 1.31 0.01
53
,,_--',.p.:u
= M --"-'-,,
53(181.7)/(10.72)(6 2}
:;:;=.-
-'--
1.311b/ft~;
le
nold
nu be
fr
Re
ac
ar
ar
(Chern. Eng., ni
lo
fr
I::!.h~o I::!.PIOO
0.0216(0.0182)(36.7)[(289)2/6,346
LlPlOO
0.19 psi/IO
'Nile
0.5(155,3'00
0.021Wh(Q2/d
.W no termin fittin fo ac series (ChemEng.,
th nt
ft
.;.. 77,6~0;f=
psi/l0
ft
·.·.26
18
lo
10 30 36
Total
pipe an
Segment fo lOO Flow,
Flow
.:.'.Ac.tual length
'(jyer'ill
0.02
quival nt length ro tables-inPart
Ft
*Oneelbowfo
0.022
as follows: 50
.Elbows Sharp tee ,E lo
density,
th
50.6(Qld)(p/JL)
Re
,·Entran
'-'-':"'~
late th
(50%)--_ 0.19 (- 144. )2
Riser,
Liquid Density
calc lati ns
in
lO (50% 0.0574
Downcomer
Ib/h
de ig
,3
calc lations F/
Flowrate;
affe ts
I.D.
-especially wh re large-diam te lines are nece ary.-Un,ec no ical reboil line ar ju carele ly versiz po rly ro ted.
Example de
nt
in fr
is fu wh el vatio adj tm nts ig ts during raphic piping de ign, be at at coefficient fo P2 betw th downco an ri no le If an ns
ti n. diff renc
arrang
Downcomer-For
fricti n-lo
al ad to ve
ar
fl
20
82 50%flow $egment;2 fo 100
pr
relo .o
th
nc
r:
' A P : :; { ) .1 9 ( 6 4 / i O ) . f Dec. 23 1974 pp. 58-66 fo co~plete
Hence:
D.Ptoo(50%) te
50
100% Flow,
Flow,
Actual length
18
Elbo 24 nt an
lo
24 48
Total
68
verall pr
I1
re lo
th
1.01(80/100)
ri r:
0.34(68/100)
downcomer,
.a
1.04 ps
ri
an
in reboil r: 7 p
..
..
Total
fo this
Riser-Since th le pipe 0.3474Jt ti n, we
NI
is
-i
ip
.P
le
late th
ap r-phas
yn ld
NIle
tain
fricti
D.PlOo
0.000336(fIPv)(W
D.p!oo
0.000336(0.014/1.31)[(25,500)2/32,380]
D.p!oo
0.072 psi/IO
-.
availabl
re pr
ifferenc re lo sa
_'
.
."
.~,,,:._
pr
re
1.57 ps is reat 1.55 psi. Th re
te li
th
il
15.5 ft
nozzle is actuall
ft
15.55 fyis~sceptable.<. ti le in this ie will ic pipeline fo th ydra li an th rmal curring in verh ad cond nsing yste
Id
Iliq idfl ftowm dulu
pr late
inc th draw ff
fa
ft
in th is ndle no determine th two-phas
th
288(1.535)-3(4.05)
0 .0 1
10 ld
termin
ff le th b'1itituting into Eq. (9):
WvldfLv = 6 3 1 2 5 5 00 ) 7 .9 8
we
ps
(1/288)[(36.7)(13.5)
availabl than th al
J.D.
al
NIle
this
wn
tu ampl
1.55
th
in th nditions
',.,:'.
fr
'jJ""t<"'""
hvdraulic-svstems design and
nu be the- a ut ho r o f fields, a n h a t au g
fo th design of proces layout graphi piping an •~
W. K el lo g
was associate C o i n E ng la n a n
.•mecnamca engineerin from th ._ ._ .. U ni ve rs it y o f B u a pe st .
.•...
.......•....•.
t.
ad Th equipment ar param ters fo Ineeting
li istill ti li
th
th to ipin
ic ta li ti
th
ig th
Hoff .,
ravity-flo
reflu
Horizontal condensers-
lo
circuits.
II
12.
type of condensation
offers
wide ange of clas ificatio
Th
lIb, vapor
tatic- ea
pres ur
difference
.P
II (1) .p
to
ce D . p e ; and
Chern.Eng.,
es
if
D.pcv:
th
(2)
following:
Two-stag
th condensation
Eq. (3)
lation. ch
ip ipin
"F
io ap
th r,
Cbem. Eng.,
1975.
densities, p, in lh/ft"; an
inimal
1 13 .
CHEMICAL ENGINEERIN
SEPTEMBE
15 1975
dimensions
-fJh Pr
~~t
f"=~*~J"
COO~~i
Poin
e. Baturate
liquid {sheiiside condensation a.
atuf3t8
Vapor
nerally, in
nd nsin
yste
th
ni lo
in th
psi/lO ft. Inle an tle re istance to pr ce quip nt ally take nsid rabl portio th pipeline re istanc an ld no be ignore in th calc lations re th ti is unusual.) In
riz ntal cond ns rs cond nsatio tak plac in th ll is give lowe re istanc than th tube id baffle (o baffle in th xc ange is in th rizontal plan thro gh th xc anger' nt rlin If ne ary, tw inle an tw tl nozzle an alv. th tota fl w, an
redu th metrical.
ntranc in
an
xi re istanc le
nsid rably.
F/
co le
tr before
fo F/l torag
ll
ir
fl
th
130 CHEMICAL ENGINEERIN
SEPTEMllI~
15 IY75
Contro valv
in th
leg (Z
ld be lo at at return' li an pr tr fficient tatic ad before th valv inle will pr vent vaporizati acro th valve pr duct co le ld no re iv liquid-vap ixture fo these condensers Verticalcondensers-Arrangements with it -flo tl ts in F/2 nd svsicms
im nsio
in F/3), th
dimension ZI is
alle
ipin
ig
2' an
than
th
lo al lo isidentical (fo xa pl fl w) li id ip intermittently th nd ns will no
afte th an
ld be pr
re
with gr atly th l; perate well
Zl (F/2b). ingle-pas vertical condenser is re itable fo liquid bc ling than ri ntal ne al lo ig an be adju te within reat rang than with rizontal nd ns rs (F/ ). Th requir liquid
than as
(see F/3a). larg
ia
te
F/ than th th
ravity-flo
refl id
line
th changer's designer. Th ydra li balanc F/ (1/144)(H
fo th
P'2)
arrang
nt
1/144)H
al lo p. th ar nt (F/3 lo li is an be pene at redu nd nsat fl to th lo fill it li id With this type ting th pres re differenc acro th vent valv ld ti points th nt line to lo ations wh re pr re ar pe te to be ab qual
wn
(4)
.P
"here .P exchanger, 6.Pe' .P "and ntrol- alve (i any) 6.Pcv, resistances: .P
betw le il
.P
!::"Pe
(5)
6.pcv
le atio ifferenc as xpre fr q. (4), th nd ns r' tl an th reflu inle noz-
where
is th
av ra
nsit
densit
nd nsat
in th
in th
rtical
an
refl
verh ad line fo ydro arbo di tillatio F/ piping is th re lt th th rm ip ff in ra ity-refl nd nsation. Fo th yste wn in F/4
line is
fl
In
it -flo
nd
In .t arrang eads), act al pre the calc lations
reversal
in
pu
whic
tu
th
th nt
tati into
r:
(7)
eal lo p. prevents flo
arrangements
Typi al
(6)
1446.P)
th
Pu ped-reflu
te
lo
nt (b id th re difference .P
al
(8)
is F/
nd ns r'
tl
an /2 If th ra ity-fl
line This lo
refl
an be
line terminat
fo
in
ld F/
diff renc
rtical
where
will be
(9) isus all
131 C m ;I I1 1C A L E NG [N EE IU N
S EP TE MB E
1 5 1 97 5
vapo density and
is vapor-liquid
i : · _ ~ . Th
simplest overhead line g!V8S the srnaitest pipe SiZ9.
in
bc ol the
li id
g:"avit'/-frovoJ
cutlet line
Eq
D..P
8) !:lP
!:lP
(10)
!:lP
{lSt
ab ve
drum. backpressure (P2H2) pressure difference betwee (2) the lower h",;ld ((';Ii Il
static-head
greater
vapor static greater the condclIs;] tion, greatf tive
course
bad.pn',.sul'e.
P2H2 be omes po i-
ir« ()lllJc.ll'
outlet
-l
Eq. ( 1 ( ) sll()\\'s ystem. This rnus: i ( lus'c's. D.l'p, an
exchange
re ista ce
!:lPe:
(11) !:lpl' ranges
!:lPe
rWlwecn
frorn
0.:) to
psi.
The maxiruu possible condenser-centerline belo th l~cflllXdr (dimen io calclllakd froru h . p}J 'Dim nsiona
relation
fo
!:lP
cond nser at grad
132
CHl~MICAL ENGINEERING SEpTlilllER 1 \ I !! '/ '
pp
D.pe)
location
Frot
flo
PI
re sider:
th
rh ad
ap
line an be negl
te
n-
Expressing =::
In layo ir in ac tive ti levatio
(144/P2)(M
de ign, rdan ad fro
lu flo
ally th refl dr it th requir th refl pu p. F/5
is le at (n iim nsions
grad
is nd
fl
(13)
an
irable lo F/
in th
ns
\J
surges. sl g-flo
.Li
region.
)I/2,
133 C HE M C A
E Nf i N EE R N G
S EP TE MB E
1 5 1 97 5
th
velo it
(cal
late
with tw
72·i
dis.
overhead ·!!n:;-
'-.
tn";',,
>7'L21,,,,"
\~~~
di
~_.-,-'P:=
al
an iChcm. Eng. June ap as ar 23,1975, p. 14 ), lo re io in F/6 ar al availabl fo vertical fl ws th ap th ap r-phas an liquid-p as lo ti ar nt ti tablis
th ne al
ak
in th appr priate fl regi n. it ri fo le ting
ar
il tv
th
th
po ible
it
bu
no
Equipmellt ~l'q\~l~d,
1',1
I.
EN(;INI:,i:,I;'INi;SlJ"II:~lIillt
al (c in Il wrat
avit -II'l\ ll ranu nt LIIIOI.'. th lI,inll ~nce la;o
Iki()\\ I'"
al an
alte nati (el) changing
arrangement
:H CIlEMICAL
ill ihe
H,l\{;II,,',·
al1d ldlw. dillin, pipe run-. fIJI ;tll''1II;ltivc to gravltv-Illl ;ULlll
to
by (a incr asin nd ns r' le line an
(';11) be minimize
jii<)\'idilll;
dClS('f
itable line iz ar
l«:
systt·lll. Ih,
II
av ay
dl<>P
pn'ss\j!('
!'Cdu('ille;
F/6
ia ra
fl,,\\
t'l;',
tr tu is de ig ar
te wn
