Zick Analysis for Saddle Support

Saddle Developer:

Meca Enterprises Chris Rosencutter [email protected]

Description:

Perform analysis of a horizontal vessel supported on two saddles. The program performs a complete analysis of teh vessels based upon L. P. Zick's analysis procedure. The program allows the user to specify the wind load, thermal loads, liquid load, and seismic loads on the vessel. A complete analysis is also performed on the saddle, calculating stresses on bolts, base plate, web, stiffeners, and wear plate.

Platform:

Saddle is a Microsoft Excel spreadsheet. It requires MS Excel 2000 or later to run.

Units:

English or Metric (Click of the button automatically toggles all inputs and results)

Sample Output:

The following pages are the output from the Saddle spreadsheet. As an example, we have simulated an example of the Zick analysis performed in the “Pressure Vessel Handbook” by Megyesy. The example in Megyesy does not address the design of the saddle itself, so there is only a comparison of the vessel stresses. In the output you will see a note symbol that looks like this Æ If you double click this note, you will receive further explanation of the output.

Purchase:

You may purchase this program at www.mecaconsulting.com .

Saddle v1-1 per "Pressure Vessel Design Manual" by Dennis R. Moss Customer: Meca Desc: Example from Pressure Vessel Handbook

H

Project: Pg 93 by: CR

H

L

B Fixed Saddle

A OD ts P Pe L H A B HType th V I Exp Z I Sc Tinst Tmin Tmax u fc S Fys Fy Emod Fbolt Fvbolt Av JE W

Sliding Saddle

Ls

Vessel Information Outside Diameter of Vessel Corroded Thickness of Shell Internal Design Pressure External Design Pressure Tangent to Tangent Length of Vessel Depth of Head Distance from Head Tangent to Saddle Center Line Height from vessel centerline to bottom of saddle Head Type Corroded Thickness of Head Wind Design (ASCE 7-98) Design Wind Speed Importance Factor Exposure Seismic Design (UBC 1997) UBC 1997 Seismic Zone Importance Factor Soil Coefficient (SA, SB, SC, SD, or SE) Temperature Installation Temperature of Vessel Minimum Temperature of Vessel Maximum Temperture of Vessel Coefficient of Friction between Saddle and Concrete Allowable bearing pressure on concrete Material Properties Allowable Stress: Vessel Shell Yield Stress of Shell at Design Temperature Yield Stress of Saddle Modulus of Elasticity of Saddle Allowable Tensile Stress on Bolts Allowable Shear Stress on Bolts Coefficient of Thermal Expansion of Vessel Joint Efficiency Weight Total Weight (If zero, program will estimate)

A 120.0000 1.0000 250.00 0.00 960.00 21 48.00 69.00 Hemis 1

in in psig psig in in in in in

0 mph 1 C 0 1 SC 70.00 70.00 70.00 0.45 750

Deg. F Deg. F Deg. F

17,500 38,000 36,000 2.900E+07 20,000 10,000 7.00E-06 0.85

psi psi psi psi psi psi in/in/F

psi

600,000 lbs



wp wb

tw Theta

Lh

B

d1

d1

tb Lrib

E F wb d1 tb wp Lh tw

F

E

Saddle Information (Note Click "Std Dims" button to get a standard saddle) Width of Saddle perpendicular to Longitudinal Axis Theta = 120.15 104.000 Width of Saddle at Bottom (along Longitudinal Vessel Axis) 9.000 Width of Saddle at Top of Saddle (along longitudinal Vessel axis) 24.000 Distance from Outside of Baseplate to First Rib 0.000 Thickness of Base Plate 1.000 Width of wear plate 24.000 Wear Plt ext. above Horn 1.000 Thickness of Wear Plate 0.750

Nr Ribs Spaced Evenly

Toward Fixed Saddle Yc Ye

J

d1

tw Sliding Saddle Bolt shown in cold as-installed Position

d2 Lb tweb J Nr Nb Dbolt Ww

d2

in in in in in in in in

F

Saddle Information Distance from Outside of Baseplate to First Rib Center to Center bolt spacing in transverse direction Thickness of Web Thickness of Ribs Number of Ribs Number of Anchor Bolts per Saddle Nominal Diameter of Bolt Fillet Leg Size (Web to Baseplate)

Lb

0.000 80.000 0.75 0.75 2 2 1.250 0.750

in in in in

in in



Calculated Parameters Rm Rs Ls Theta ThetaW

Mean Radius of Shell Radius of Shell Saddle Spacing: L-2*A Saddle Angle: 2*Atan((E-2*d1)/OD) Angle of Wear Plate

Wtot

User Entered Total Weight

59.500 60.000 864.000 120.1 122.1

in in in Deg Deg

Calculate Weights

De zg Alpha Kz Cf Gq qz Afl Flw Aft Ftw Ca V Fls Fts Ye Yc Flt Fl Ft Qo Q1 Q2 Q

Wind Loading: (Based upon ASCE 7-98) Effective Diameter based upon Table 3-24 Constant from table 6-4 Constant from table 6-4 2.01*((B+OD/2)/zg)^(2/Alpha) Shape Factor Gust Factor (Rigid Structure) Wind Pressure: 0.00256*Kz*V^2*I PI()*(De/12)^2/4 Af*Cf*Gq*qz De*(L+2*H)/144 (Aft*Cf*Gq*qz)*0.5 Seismic Loading: (Based upon UBC) Seismic Coefficient based upon Soil and Zone 2.5*Ca*I*W / R V / 1.4 V / (2 * 1.4) Thermal Expansion Maximum Expansion of Vessel Maximum Contraction of Vessel Frictional Force due to Expansion/Contraction (u*Wtot/2) Saddle Reactions Maximum Longitudinal Force: Max(Flw, Fls, Flt, Flp) Maximum Transverse Force: Max(Ftw, Fts) Operating Load on Saddles: (Wtot)/2 Reaction due to Long Force: Wo/2+Fl*B/Ls Reaction due to Tran Force: Wo/2+3*Ft*B/E Maximum of Q1 or Q2

600,000 lbs 141.6000 900.0000 9.5000 1.3353 0.8 0.85 0.00 109 985 -

in

psf ft^2 lbs ft^2 lbs

0.0000 lbs lbs lbs 300,000 300,000 300,000 300,000

in in lbs lbs lbs lbs lbs lbs lbs


A./Rs K1 K2 K3 K4 M1 M2 S1 S2 S4 S6 Check # 1 Check # 2 Check # 3 tes tes1 tes2 S9 S10 S11 S12 fx fp Element Shell Wear Plt Web Baseplt c1 c2 Is As Beta K1 fh ft d M fb fb Ab Bp fbplt


"K" Constants from Figure 3-46 K5 = K6 = K7 = K8 = K9 = Longitudinal Bending 6*Q*(8*A*H+6*A^2-3*Rm^2+3*H^2)/(3*L+4*H) 3*Q*((3*L^2+6*Rm^2-6*H^2-12*A*L-16*A*H)/(3*L+4*H)) Long. Bending @ Saddles w/o Stiffeners - Tension: M1/(K1*Rm^2*ts) Long. Bending @ Saddle w/o Stiffeners - Compression: -M1/(K7*Rm^2*ts) Long. Bending @ Midspan: +/- M2/(pi()*Rm^2*ts) Tangential Shear Tang. Shear - shell not stiffened A>0.5R: (K2*Q/(Rm*ts))*((L-2*A)/(L+4*H/3)) Circumferential Bending Lh >= Rm/10: 1.00 <= 5.95 Is A <= 0.5*Rm: 48.00 >= 29.75 Wp >= wb+1.56*(Rm*ts)^0.5 24.00 <= 36.03 Check # 1 & # 2 did not both pass: ts Check # 3 did not both pass: ts Check # 1 & # 2 did not both pass: ts^2 Bend @ horn L>=8R: -Q/(4*ts*(wb+1.56*(Rm*ts)^0.5))-3*KK6*Q/(2*tes2) Bend @ horn L<8R: -Q/(4*ts*(wb+1.56*(Rs*ts)^0.5))-12*KK6*Q*Rs/(L*ts^2) Since A>0.5*Rs --> Add'l Tension in Head = 0 Circ Compression: -KK5*Q/(tes1*(wb+1.56*(Rm*tes1)^0.5)) Pressure Stresses Longitudinal Pressure Stress P*Rm/(2*ts) Circumferential Pressure Stress P*Rm/ts Saddle Design - Web b h Area I d A*d in in in^2 in^4 in in^3 48.167 1.000 48.2 4.01.E+00 0.50 2.408E+01 36.084 0.750 27.1 1.27.E+00 1.38 3.721E+01 0.750 37.250 27.9 3.23.E+03 20.38 5.692E+02 9.000 1.000 9.0 7.50.E-01 39.50 3.555E+02 Area = 112.2 A*Y = 9.860E+02 Dist from Id of Shell to Center of Gravity for Saddle (A*Y/Area) Dist from Center of Gravity to Base Plate Moment of Inertia of Saddle Area of Saddle Pi() - Theta/2 (1+COS(Beta)-0.5*(SIN(Beta))^2)/(PI()-Beta+(SIN(Beta))*(COS(Beta))) Saddle Splitting Force: K1*Q Tensile Stress in Saddle: fh/As B-Rs*Sin(Theta)/Theta fh * d Bending Stress in Saddle: M*C1/I Saddle Design - Wear Plate Bending Stress in Wear Plate: 6*Q*K5*wb/(8*tw^2*Rs) Saddle Design - Baseplate Bearing Area: E * F Bearing Pressure: Q/Ab (3*Q*F)/(4*E*tb^2) = = = = =

0.8000 0.3357 1.1686 0.8775 0.4004

0.7595 0.0369 0.6041 0.3399 0.0529 6.372E+05 5.603E+07 536 -298 5,038

in-lbs in-lbs psi psi psi

5,153 psi FALSE FALSE FALSE 1.0000 1.0000 1.0000 -18,694 -10,385 0 -6,323

in in in psi psi psi psi

7,438 psi 14,875 psi A*d^2 in^4 1.204E+01 5.117E+01 1.160E+04 1.404E+04 I= 8.79 0.21 2.894E+04 112.2 2.093 0.2038 61,137 545 49 3.005E+06 913

Itot in^4 1.606E+01 5.243E+01 1.483E+04 1.404E+04 2.894E+04 in in in^4 in^2 rads lbs psi in in-lbs psi

17,624 psi 936 in^2 321 psi 19,471 psi


Tension? Pb Abolt fal fv M e E/6


Saddle Design - Anchor Bolts Longitudinal Load Is Qo > Q1? 300,000 < 300,000 Since Q0>Q1 then Tensile Load will exist Each Bolt: ((Q1-Q0)/(Nb)) (Pi()/4) * Dbolt^2 Bolt Tensile Stress: Pb/Abolt Shear Load (Assume Fixed Saddle takes entire load) Shear Stress: Fl / Abolt Transverse Load Transverse Moment: Ft * B M / Q0 E/6 Since e < E / 6 --> There is No Uplift

FALSE lbs 1.23 in^2 psi -

psi

in-lbs in 17.333 in



Saddle Design - Ribs Outside Ribs Lrib Lotrib Pr Ar fa I1 C1 r L1 Lr Cc Fa fu M fb SR Litrib Pr Ar fa I2 C2 r L2 Lr Cc Fa fu M fb SR

Rib Spacing: (E-2*d1)/(Nr-1) Tributary Length: Min (e , 0.5*Lrib) Axial Load on Ribs: Bp * F * Lotrib Area of Web and Rib: J*(F-2*d2-tweb) + tweb*(Lotrib-d1) Compressive Stress: Pr / Ar (J/12) * ((wb + F) / 2)^3 (wb + F) / 4 Radius of Gyration: (I1 / Ar)^0.5 Height of Saddle: B - Rs * Cos(Theta/2) Slenderness Ratio: L1 / r (2*PI()^2*Emod/Fy)^0.5 (1-Lr^2/(2*Cc^2))*Fy/(5/3+3*Lr/(8*Cc)-Lr^3/(8*Cc^3)) Unit Force: Fl / (2 * E) Bending Moment: 0.5 * fu * e * L1 Bending Stress: M * C1 / I1 Stress Ratio: fa/Fa+fb/Fb Inside Ribs Tributary Length: Min (e , Lrib) Axial Load on Ribs: Bp * F * Litrib Area of Web and Rib: J*(F-2*d2-tweb) + tweb*Litrib Compressive Stress: Pr / Ar (J/12) * ((wb + F) / 2)^3 0.5 * Wb Radius of Gyration: (I2 / Ar)^0.5 Height of Saddle: B - (Rs^2-(E/2-d1-Lrib)^2)^0.5 Slenderness Ratio: L1 / r (2*PI()^2*Emod/Fy)^0.5 (1-Lr^2/(2*Cc^2))*Fy/(5/3+3*Lr/(8*Cc)-Lr^3/(8*Cc^3)) Unit Force: Fl / (2 * E) Bending Moment: 0.5 * fu * e * L2 Bending Stress: M * C2 / I2 Stress Ratio: fa/Fa+fb/Fb

104.0000 52.0000 150,000 45.19 3,320 2.808E+02 8.250 2.493 39.067 15.7 126.1 20,853 0.000E+00 0.16

in in lbs in^2 psi in^4 in in in

104.000 3.000E+05 84.19 3,563 8.640E+02 12.000 3.204 39.1 12.2 126.1 21,043 0.000E+00 0.17

in lbs in^2 psi in^4 in in in

psi lb/ft in-lbs psi

psi lb/ft in-lbs psi


Description Shell not stiffened Horn of Saddle - Shell Not Stiffened Horn of Saddle - Shell not Stiffened Circumferential Compressive Stress Longitudinal Tension at Saddles Longitudinal Bending @ Midspan Tension in Head Tensile Stress in Web Bending Stress in Saddle Bending Stress in Wear Plate Bending stress in Baseplate Bearing pressure on Concrete Bending Stress Axial Stress S.R. for Bending + Axial Bending Stress Axial Stress S.R. for Bending + Axial Tensile Stress Shear Stress

Stress Summary SR Result Tangential Shear S6 0.37 PASS Circumferential Bending S9 0.71 PASS S10 0.40 PASS S12 0.33 PASS Combined Stress - Tension S1+fx 0.54 PASS S4+fx 0.84 PASS S11+fp 0.80 PASS Saddle Web ft 0.03 PASS fb 0.04 PASS Saddle Wear Plate fb 0.74 PASS Saddle Base Plate fbplt 0.82 PASS Bp 0.43 PASS Saddle - Outside Ribs fb 0.00 PASS fa 0.16 PASS ftot 0.16 PASS Saddle - Inside Ribs fb 0.00 PASS fa 0.17 PASS ftot 0.17 PASS Saddle - Inside Ribs fa 0.00 PASS fv 0.00 PASS Equation


Actual

Allowable

5,153

14,000 psi

(18,694) (10,385) (6,323)

26,250 psi 26,250 psi 19,000 psi

7,974 12,475 14,875

14,875 psi 14,875 psi 18,594 psi

545 913

21,600 psi 23,760 psi

17,624

23,760 psi

19,471 321

23,760 psi 750 psi

3,320 0.16

23,760 psi 20,853 psi 1.00

3,563 0.17

23,760 psi 21,043 psi 1.00

-

20,000 psi 10,000 psi

Zick Analysis for Saddle Support

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