Size Your Pipe

Calculate the head loss in a pipe with fittings 3alculation will allow you to estimate the head loss /pressure drop in a pipe with a nice clean internal surface# In general head loss is higher in small diameter pipes and long lengths of pipe# Diameter is the greater of the 2 impacts# $ype in your varia%les and look for the answer %elow# $here $here are two sections# In this first section you can easily convince your self of importance of pipe diameter# diameter# 4ust type in diffferent sies for same flow rate and same pipe length

#o Fittings Fitting s section VARIABLES  !"PE I# "$%RSELF( "$%RSELF( "ou 'ust 'easure this flow using a buc)et and watch or base *our s*ste' upon a chosen +olu'e flow rate( !he add the pipe properties ,dia'eter and length- re.uired 7 galls per Imperial gallons minute per minute 6 10 Inches Inches 2 6 Feet Feet 10 10

Decide which units you want to work in volume of water flowing through the pipe internal diameter of pipe in millimetres length of the pipe in metres

itres per minute 8 mm 25 etres !

Part 1 Answer below here head loss " no fittings in pipe system

Feet

Feet

etres

1#2

0#!

0#6

$his answer needs to %e modified if there are valves& %ends and other restrictions in the pipework# $his is done %y adding the relevant num%er of pipe diameters to the a%ove answer using the ta%le %elow 'owever this top section is the most important in most cases 9ipe diameters:single restriction

/o #$! change an* infor'ation in this table

) !0 20 8

(pen gate valve )0 degree el%ow *5 degree el%ow swept )0 degree %end

For e+ample if there are the following restrictions in the pipe system then you do following

Fittings section VARIABLES  !"PE I# "$%RSELF In this table $#L" enter date in  "ELL$0 colu'n

;o# (f
,-uivalent diameters:restriction

$otal diameters due to restriction

(pen gate valve

1

)

)

)0 degree el%ow

1

!0

!0

*5 degree el%ow

1

20

20

swept )0 degree %end

1

8

8

Part & Answer below here ,+tra e-uivalent pipe length due to fittings

Feet

Feet

etres

11#2

!!#5

1#.

'aving done this you would then go %ack to part 1 and change the length from 5 metres to /5  1#.  6#. metres $otal head loss for this system as defined here would then %e

Final Answer below here $otal system head loss

Feet

Feet

etres

2#5

1#*

0#)

 "our  " our choice of pu'p would w ould then be based upon u pon this nu'ber