a 4 5 1 c c 3 - omcmech.com · 3) asme bpvc section viii div ii c. description: male stab for...

SECTION A-ASCALE .35

1

1

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2

3

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5

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A A

B B

C C

D D

SHEET 1 OF 1

DRAWN

CHECKED

QA

MFG

APPROVED

Bobby DePriest 7/27/2017

DWG NO

final assembly

TITLE

SIZE

DSCALE

REV

.35

A

A

PARTS LISTDESCRIPTIONPART NUMBERQTYITEM

Top Head11 Flanged Gimmick12 Hanger13 load lug 344 dummy flange

bolt85

spear16 Male Stab17 Lock Pin48

36

1

2

4 5

8

SECTION B-BSCALE .6

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A A

B B

C C

D D

SHEET 1 OF 1

DRAWN

CHECKED

QA

MFG

APPROVED


DWG NO

Flanged Gimmick

TITLE

SIZE

DSCALE

REV

.6

B

B

11.4375

R3.250

4X

R.750TYP

45°

5.1008.000

15.01

35.810°

(3.000)3.750

2.250

R1.544

R.75

1.488 THRUØ.005 AB

9.625

11.000

A

B

C

SECTION D-DSCALE 1 / 2

DETAIL BSCALE 2 : 1

VIEW E-ESCALE 1 / 2

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C C

D D

SHEET 1 OF 1

DRAWN

CHECKED

QA

MFG

APPROVED


DWG NO

Male Stab

TITLE

Male Stab

SIZE

DSCALE

OMC Mechanica

REV

1 / 2

DIMENSIONS ARE IN INCHES

XXX .005

XX .010

X .015

D

D

B

E E

1

1 DIMENSION TO THEORETICAL INTERSECTION

2.500

4.995 - .005.000+

9.985 .010

4.267

1.50

.375.003

.375.003

.375.007

4.262 .003

R.13

R.13

27.524 2X 7.00

90°

2.500 - .000.005+

.005AB

A

B

4.803 5.000

20°

R.13

2.00 4X

3.526 4X

.25 X 45° 2X

R.25

R.25

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A A

B B

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D D

SHEET 1 OF 1

DRAWN

CHECKED

QA

MFG

APPROVED


DWG NO

Lock Pin

TITLE

SIZE

DSCALE

REV

2 : 1

2.499 - .002.000+

6.00

.13 X 45° Chamfer

SECTION B-BSCALE .4

SECTION C-CSCALE .4

DETAIL DSCALE 2 : 1

1

1

2

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A A

B B

C C

D D

SHEET 1 OF 1

DRAWN

CHECKED

QA

MFG

APPROVED


DWG NO

Top Head

TITLE

SIZE

DSCALE

REV

.4

B

B

C

C

D

10.000 - .000.010+

17.00

16.00

2.500 - .000.003+

11.43751 3/8-6 UNC - 2B 2.75 MIN

A

B

Ø.010AC

C

Ø.005CB

5.100 .010C 4X

45°

8XTYP

90°4X

5.828 1


20° R.13

R.13

3.557

7.114

7.1142.625

TYP

13.750

SECTION A-ASCALE 1 : 1

DETAIL BSCALE 8: 1

A

A

B

1

1

2

2

3

3

4

4

5

5

6

6

7

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8

8

A A

B B

C C

D D

SHEET 1 OF 1

DRAWN

CHECKED

QA

MFG

APPROVED


DWG NO

spear

TITLE

SIZE

DSCALE

REV

1 : 1

66°

.172.001

.173.002

1


R.015 2X

R.031 2X

4.166

4.570

2.703

45°

.500

3.485

10.000

9.556

OMC Mechanica SpearP/Nxxxxxx Prepared By: Bobby DePriest, P.E.

A. OBJECTIVE:To document the design of the Spear, P/N xxxxxxxxx of the Widget Assembly. To demonstrate that the assembly meets the

requirements of API 16C . Third party certifier is Det Norse Veritas.

B. REFERENCES:1) API 6X Design Calculations for Pressure Containing Equipment 1st Edition, March 2014

2) Roark's Formulas for Stress and Strain 8th Edition

C. DESCRIPTION:Spear for Widget Assembly

D. Material1). AISI 4130 75ksi min yield

ALLOWABLES:

≔Sy ⋅75000 psi Minimum material yield strength per material specification

≔SE =Sy 75000 psi Maximum allowable equivalent stress at proof test pressure per API 16C, at the most highly stressed distance into the pressure vessel wall, computed by the distortion energy theory method. (used when calculating von mises equivalent stresses)

≔Sm_allow =⋅―23

Sy 50000 psi Allowable general primary membrane stress at operating condition(Sm) per API 6X

≔St_allow =⋅.9 Sy 67500 psi Allowable general primary membrane stress at test pressure ( ) per API 6XSt

≔k 1 Stress intensity factor(k) per API 6X

≔PLb =⋅⋅1.5 k Sm_allow 75000 psi Allowable local membrane plus bending per API 6X

≔τav_allow =⋅.6 Sm_allow 30000 psi Allowable average shear stress( ) at test pressure per API τav6X

Page 1 of 4


Stresses at Section C

INPUTS: ≔OD =-3.485 in ⋅.005 in 3.48 in Minimum spear o.d. per dwg# xxxxxx≔ODPEL =+⋅4.570 in ⋅.005 in 4.575 in Maximum diameter per dwg# xxxxxx

≔ID =+⋅2.703 in ⋅.005 in 2.708 in Maximum i.d. per dwg# xxxxxx

≔t =―――-OD ID2

0.386 in Minimum wall thickness at C

≔Pw ⋅5000 psi Maximum internal working pressure≔Pt =⋅1.5 Pw 7500 psi Test Pressure≔Po ⋅0 psi Ambient Pressure

CALCULATED VALUES:

≔b =―ID2

1.354 in Maximum inside radius

≔a =――OD2

1.74 in Minimum outside radius

≔Amin =⋅―π4

⎛⎝ -OD2 ID2 ⎞⎠ 3.752 in2 Minimum Cross-sectional area at C

Area for pressure end load (PEL) acting on load shoulder≔APEL =⋅―

π4

ODPEL2 16.439 in2

Area for PEL acting on load shoulder≔Aaxial =⋅―

π4

ID2 5.76 in2

≔Ft =⋅Pt Aaxial 43196 lbf Axial Force at test pressure

≔FPEL =⎛⎝ ⋅Pt APEL⎞⎠ 123292 lbf Force on load shoulder at test pressure

STRESSES AT TEST PRESSURE:

≔σ1 =⋅Pt ―bt

26308 psi Membrane hoop stress

≔σ2 =――Ft

Amin11513 psi Membrane axial stress (negative value indicates compressive stress)

≔σ3 =-Pt -7500 psi Radial stress on I.D.

≔Se =‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾---++σ12 σ2

2 σ32 ⋅σ1 σ2 ⋅σ2 σ3 ⋅σ1 σ3 29355 psi Von Mises on I.D.

≔DFe =―SE

Se2.6 Design Factor > 1 = o.k.

Page 2 of 4


Stresses due to Reaction at Load Shoulder:Because of the o-ring groove, the load shoulder is divided into two load bearing surfaces. The anticipated failure mode would be shear on a plane coincident with the angle of maximum shear stressses, often referred to as "half angle shear". It is assumed below that the load is shared equally over the two shear planes.

INPUTS:

Lower Upper

≔DCA =⋅3.624 in 3.624 in Diameter at centroid of lower shear plane ≔DCB 4.445 in

≔WA ⋅.363 in Width of shear plane ≔WB ⋅.326 in

≔AA =⋅⋅π DCA WA 4.133 in2 Area of shear plane ≔AB =⋅⋅π DCB WB 4.552 in2

=FPEL 123292 lbf Force on load shoulder at test pressure

≔θ °45 Angle of load shoulder

≔θτ ⋅.5 θ Angle of maximum shear plane

≔Fτ =⋅FPEL sin ⎛⎝ -°90 θτ⎞⎠ 113907 lbf Shear force acting on plane A

≔Atotal =+AA AB 8.685 in2 Total shear area


≔τ =――Fτ

Atotal13115 psi

≔DFshear =―――τav_allow

τ2.3 Design Factor > 1 = o.k.

Page 3 of 4


Stresses end of spear at D:

INPUTS: ≔t =(( ---10.00 .005 9.556 .005)) 0.434≔E ⋅30 106

≔v 0.3

≔q ――Pt

psi Variables and calculations from Roark's table 11.2 case 10b.

≔a =――ID⋅2 in

1.354

≔L14 =―116

0.063

≔Mc =⋅⋅⋅q a2 (( +1 v)) L14 1117

≔σmax =⋅――⋅6 Mc

t2psi 35587 psi

≔DFD =――SE

σmax2.1

SummaryCalculated Stress Allowable Stress Design Factor

Equivalent Stress at C =Se 29355 psi =SE 75000 psi =DFe 2.6

Shear Stress on Shoulder =τ 13115 psi =τav_allow 30000 psi =DFshear 2.3

Max stress at D =σmax 35587 psi =SE 75000 psi =DFD 2.1

Page 4 of 4

OMC Mechanica Male Stab P/Nxxxxxx Prepared By: Bobby DePriest, P.E.

A. OBJECTIVE:To document the design of the Male Stab Sub, P/N xxxxxxxxx of the Widget Assembly. To demonstrate that the assembly meets

the requirements of API 16C . Third party certifier is Det Norse Veritas.

B. REFERENCES:1) API 16C Specification for Choke and Kill Systems 1st Edition, March 2015

2) API 6X Design Calculations for Pressure Containing Equipment 1st Edition, March 20143) ASME BPVC Section VIII Div II

C. DESCRIPTION:Male Stab for Widget Assembly


ALLOWABLES:








≔τav_allow =⋅.6 Sm_allow 30000 psi Allowable average shear stress( ) at test pressure per API τav6X

Page 1 of 3


Stresses at Seal Groove(A-A)

INPUTS: ≔OD 4.995 in Maximum stab diameter per dwg# xxxxxx≔ODg -⋅4.262 in ⋅.0003 in Minimum groove diameter per dwg# xxxxxx

≔ID =+⋅2.500 in ⋅.005 in 2.505 in Maximum inside diameter at groove per dwg# xxxxxx

≔t =―――-ODg ID2

0.878 in Minimum wall thickness at groove

≔Pw ⋅5000 psi Maximum internal working pressure≔Pt =⋅1.5 Pw 7500 psi Test Pressure≔Po ⋅0 psi Ambient Pressure

CALCULATED VALUES:

≔b =―ID2

1.253 in Maximum inside radius

≔a =――ODg

22.131 in Minimum outside radius

≔Amin =⋅―π4

⎛⎝ -ODg2 ID2 ⎞⎠ 9.336 in2 Minimum Cross-sectional area at groove

≔Astab =⋅―π4

⎛⎝ -OD2 ID2 ⎞⎠ 14.667 in2 Area for pressure end loadAxial Force at working pressure (negative value indicates compressive load) ≔Fw =⋅-Pw Astab -73337 lbf

≔Ft =-⎛⎝ ⋅Pt Astab⎞⎠ -110005 lbf Axial Force at test pressure


≔σ1 =⋅Pt ―bt

10695 psi Membrane hoop stress

≔σ2 =――Ft

Amin-11783 psi Membrane axial stress (negative value indicates compressive stress)

≔σ3 =-Pt -7500 psi Radial stress on I.D.

≔Se =‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾---++σ12 σ2

2 σ32 ⋅σ1 σ2 ⋅σ2 σ3 ⋅σ1 σ3 20672 psi Von Mises on I.D.

≔DFe =―SE

Se3.6 Design Factor > 1 = o.k.

Page 2 of 3


Stresses due to Reaction at Shear Pins:

INPUTS: ≔Dhole =+2.500 in ⋅.005 in 2.505 in Maximum hole diameter

≔n 4 Number of holes≔Aside 6.36 in2 Shear area at side of hole

≔Ahole =⋅π⎛⎜⎝――Dhole

2

⎞⎟⎠

2

4.928 in2 Area of hole diameter

≔Atensile ⋅58.8 in2 Tensile Area≔LOE ⋅1.53 in Length of pin engagement

≔Abearing =⋅―――⋅π Dhole

2LOE 6.02 in2 Bearing area at pin interface

≔PEL =⋅⋅Pt ―π4

OD2 146968 lbf Pressure end load


≔τtear =――――PEL

⋅⎛⎝2 Aside⎞⎠ n2889 psi Average tearout shear stress

≔σtensile =――PEL

Atensile2499 psi Average tensile stress

≔σbearing =―――PEL

⋅Abearing n6103 psi Average bearing stress

≔DFtear =―――τav_allow

τtear10.4

≔DFtensile =――St_allow

σtensile27 Design Factor > 1 = o.k.

≔DFbearing =―――Sy

σbearing12.3

SummaryCalculated Stress Allowable Stress Design Factor

Equivalent Stress at Groove =Se 20672 psi =SE 75000 psi =DFe 3.6

Tearout Stress =τtear 2889 psi =τav_allow 30000 psi =DFtear 10

Tensile stress at shear holes =σtensile 2499 psi =St_allow 67500 psi =DFtensile 27

Bearing Stress on shear holes =σbearing 6103 psi =Sy 75000 psi =DFbearing 12

Page 3 of 3

OMC Mechanica Top Head P/N xxxxxxx Prepared By: Bobby DePriest, P.E.

ALLOWABLES:

≔σyb ⋅105000 psi Minimum Material Yield Strength for bolt

≔σint ⋅75000 psi Minimum Material Yield Female Thread

≔σcb 75000 psi Minimum Material Yield C'bore/Plate/Flange

≔σb_allow =⋅.83 σyb 87150 psi Allowable Tensile Stress in bolt per API 16A

≔τb_allow =⋅.577 σb_allow 50286 psi Allowable Shear Stress in bolt

≔τint_allow =⋅⋅.577 .667 σint 28864 psi Allowable Shear Stress in Female Thread

≔τcb_allow =⋅⋅.577 .667 σcb 28864 psi Allowable Shear Stress in c'bore/plate/flange per

INPUTS:

≔Pt 7500 psi Load (per bolt, maximum of preload v/s subsequent loading)

Pressure end load from spear p/n xxxxxxx≔PEL =⋅⋅―π4

((4.575 in))2

Pt 123292 lbf

≔n 8 Number of bolts

ANALYSIS of Threads (ASME B1.1Unified Inch Screw Threads)

=σyb 105000 psi L7 Minimum bolt yield strength per ASTM A320

≔D ⋅1.375 in Nominal (basic) thread diameter

≔np ―6in

number of threads per inch

≔P =―1np

0.1667 in thread pitch

≔PDbsc =-D ⋅0.649519 P 1.2667 in basic pitch diameter of external thread

≔Dten =-D ⋅0.9743 ―1np

1.2126 in tensile stress area diameter

basic thread minor diameter≔dbsc =-⋅1.3728 in ⋅1.08253175 P 1.1924 in

08/05/17Page 1 of 3


Thread tolerances:

≔Ptol_ext =⋅⋅1 in

⎛⎜⎜⎝

++⋅.0015⎛⎜⎝――

D⋅1 in

⎞⎟⎠

―13

⋅.0015⎛⎜⎝――

D⋅1 in

⎞⎟⎠

―12

⋅.015⎛⎜⎝――

P⋅1 in

⎞⎟⎠

―23⎞⎟⎟⎠

0.008 in

=Ptol_ext 0.008 in Class 2A pitch diameter tolerance for external threads

≔Ptol_int =⋅1.3 Ptol_ext 0.0104 in Class 2B pitch diameter tolerance for internal threads

≔Dallow =⋅0.300 Ptol_ext 0.0024 in Allowance for external threads

≔Dtol_ext =⋅⋅

⎛⎜⎜⎝

⋅.060⎛⎜⎝――

P⋅1 in

⎞⎟⎠

―23⎞⎟⎟⎠

1 in 0.0182 in Class 2A major diameter tolerance for external threads

≔dtol_int =-⋅.25⎛⎜⎝――

P⋅1 in

⎞⎟⎠

⋅0.4⎛⎜⎝――

P⋅1 in

⎞⎟⎠

20.0306 Class 2B minor diameter tolerance for internal threads

Thread dimensions:

≔Dmax_ext =-D Dallow 1.3726 in Class 2A Max major diameter for external threads

≔Dmin_ext =-Dmax_ext Dtol_ext 1.3544 in Class 2A Min major diameter for external threads

≔PDmax_ext =-PDbsc Dallow 1.2644 in Class 2A Max pitch diameter for external threads

≔PDmin_ext =-PDmax_ext Ptol_ext 1.2564 in Class 2A Min pitch diameter for external threads

≔PDmin_int =PDbsc 1.2667 in Class 2B Min pitch diameter for internal threads

≔PDmax_int =+PDmin_int Ptol_int 1.2771 in Class 2B Max pitch diameter for internal threads

≔dmin_int =-PDmin_int ⋅0.43301122 P 1.195 in Class 2B Min minor diameter of internal thread

≔dmax_int =+dmin_int ⋅⋅dtol_int 1 in 1.225 in Class 2B Max minor diameter of internal thread

≔dmin_ext =-PDmin_ext ⋅0.64951905 P 1.1481 in Class 2A Min minor diameter for external threads

Tensile Stress in One Bolt:

≔Ab =⋅―π4

Dten2 1.2 in2 Stress area for flange bolting

≔Ad =⋅π ―――dmin_ext

2

41.04 in2 Stress area for closure bolting

≔Fb_allow =⋅σb_allow Ad 90228 lbf Maximum Allowable Force per Bolt

≔Fpl =⋅σb_allow Ad 90228 lbf Axial pre-load force on one bolt

≔FPEL =――PEL

n15411 lbf Load on one bolt due to PEL, neglecting pre-load

Largest of preload v/s operational load. This does not include any effects from strain of flange p/n xxxxx. See calcs for flange.≔Fbolt =max ⎛⎝ ,Fpl FPEL⎞⎠ 90228 lbf

≔σbolt =――Fbolt

Ad87150 psi

≔DFσbolt =―――Fb_allow

Fbolt1 Design Factor

08/05/17Page 2 of 3


Shear Stress in Bolt Threads:

≔w ⋅4.25 in bolt length

≔x ⋅(( +1.375 .005)) indwg# xxxx rev01

≔LOE =--w x ⋅2 P 2.537 in Length of Engagement

Geometric shear areas for internal and external threads:

≔Ashear_int =⋅⋅⋅⋅π np LOE Dmin_ext⎛⎜⎝

+――1⋅2 np

⋅0.57735 ⎛⎝ -Dmin_ext PDmax_int⎞⎠⎞⎟⎠

8.2883 in2

≔Ashear_ext =⋅⋅⋅⋅π np LOE dmax_int⎛⎜⎝

+――1⋅2 np

⋅0.57735 ⎛⎝ -PDmin_ext dmax_int⎞⎠⎞⎟⎠

5.9386 in2

≔τint =―――Fbolt

Ashear_int10886 psi Shear Stress on Internal Thread

≔τext =―――Fbolt

Ashear_ext15193 psi Shear Stress on bolt thread

≔DFint =―――τint_allow

τint2.7

=τint_allow 28864.425 psi

=τb_allow 50285.55 psi ≔DFext =――τb_allow

τext3.3

Summary:Allowable Design Factor

Bolt Tension =σbolt 87150 psi =σb_allow 87150 psi =DFσbolt 1

Internal Thread Shear =τint 10886 psi =τint_allow 28864 psi =DFint 2.7

Bolt Thread Shear =τext 15193 psi =τb_allow 50286 psi =DFext 3.3

08/05/17Page 3 of 3

OMC Mechanica Lock Pin P/Nxxxxxx Prepared By: Bobby DePriest, P.E.

A. OBJECTIVE:To document the design of the Lock Pin, P/N xxxxxxxxx of the Widget Assembly. To demonstrate that the assembly meets the

requirements of API 16C . Third party certifier is Det Norse Veritas.

B. REFERENCES:1) API 16C Specification for Choke and Kill Systems 1st Edition, March 2015

2) API 6X Design Calculations for Pressure Containing Equipment 1st Edition, March 2014

C. DESCRIPTION:Lock Pin for Widget Assembly


ALLOWABLES:








≔τav_allow =⋅.6 Sm_allow 30000 psi Allowable average shear stress( ) at test pressure per API 6Xτav

08/05/17Page 1 of 2

OMC Mechanica Lock Pin P/Nxxxxxx Prepared By: Bobby DePriest, P.E.

Shear Stress:

INPUTS: ≔OD (( -2.499 0.002)) in Maximum stab diameter per dwg# xxxxxx

≔PELstab 110005 lbf Pressure end load from male stab≔npin 4 Number of lock pins

CALCULATED VALUES:

≔Amin =⋅―π4

⎛⎝OD2 ⎞⎠ 4.897 in2 Minimum Cross-sectional area at groove


≔τpin =―――PELstab

⋅npin Amin5616 psi

≔DFe =―――τav_allow

τpin5.3 Design Factor > 1 = o.k.

08/05/17Page 2 of 2

OMC Mechanica Prepared by: Bobby DePriest, P.E.

8/5/2017 Page 1 of 6

Flanged Gimmick for Widget Assembly

Executive Summary

A finite element analysis was conducted to demonstrate that the flanged gimmick (p/n xxxxx) and load

lugs (p/n yyyyyy) for use in the Widget Assembly (p/n zzzzzzz) would be capable of meeting the stress

requirements at test pressure. Based on the results presented here it can be concluded that neither the

flanged gimmick nor the load lugs meet the allowable stress limits.

Figure 1. Section view of Widget Assembly

Introduction

The flanged gimmick is intended to be used a quick connection point on which the hanger and load lugs

will react the pressure load. This report is concerned with the load lug to flange gimmick interface as

shown in Figure 1. The hanger with load lugs is installed over the flanged gimmick with the lugs

following the j-slots in the flanged gimmick. The hanger is retained by rotating it and the lugs to the

locked position of the j-slots. The widget assembly is rated for a working pressure of 5,000 psig and thus

will be proof tested to 7,500 psig. A three-dimensional model representing the hanger, load lugs, and

flanged gimmick was built to determine if the lugs and their interface on the flanged gimmick would

meet the maximum stress allowances at test pressure.

The linear elastic finite element analysis was performed using FEMAP 11.3.2 with Nastran.

Finite Element Model

The sub assembly was modeled as a quarter model symmetric about the X and Y planes as shown in

Figure 2. The relevant dimensions of the model are worst case tolerance per the drawings listed in Table

1.

The lugs and hanger were meshed with 275346 CHEXA elements in FEMAP. The flanged gimmick was

meshed with 381158 CTETRA elements in FEMAP.

Load Lug Flange Gimmick


8/5/2017 Page 2 of 6

Table 1. Drawings Providing the Relevant Dimensions of FEA Model Components

Description DWG# Material Spec Min Yield Strength

Hanger yyyyy AISI 4130 75 ksi

Flanged Gimmick zzzzz AISI 4130 75 ksi

Load Lug xxxyyy ASTM A325 105 ksi

Figure 2. Meshed FE model used for analysis

Material Properties

Linear isotropic material properties were used in the FE analysis performed on these components.

Plasticity and other non-linear material properties were ignored.

Load Lugs

Material: ASTM A325

Modulus of Elasticity: 29,000,000 psi


8/5/2017 Page 3 of 6

Poisson’s ratio: 0.3

Flanged Gimmick and hanger

Material: AISI 4130

Modulus of Elasticity: 29,000,000 psi

Poisson’s ratio: 0.3

Loads and Constraints

The widget assembly will have a maximum internal working pressure of 5,000 psig. Prior to entering service it will be subject to a proof test at 7,500 psig internal pressure. Shown in figure 3 are the loads simulated in the FE analysis.

Figure 3. Pressure end load applied to hanger shoulder and bolt preloads applied at bolt shoulder

As shown in Figure 4, symmetry constraints were applied to the quartered faces and a fixed constraint was applied to the free end of the flanged gimmick.


8/5/2017 Page 4 of 6

Figure 4. Symmetry and Fixed Constraints applied to FE Model


8/5/2017 Page 5 of 6

Analytical Results

Allowable Stresses:

Reference: API Spec 16C, API 16A

Minimum Yield Strength

Hanger and Flanged Gimmick - σy=75000 psi

Load Lugs – σb= 105000 psi

Allowable Stresses for Hanger/Gimmick at Test Pressure:

• Von Mises Equivalent Stress: SE < 2/3 σy = 50025 psi

• Shear Stress τav < .4 σy = 30000 psi

Allowable Stresses for Load Lugs at Test Pressure:

• Tensile Stress: SE < 0.83 σb = 87150 psi

• Shear Stress τav < .577(.85) σb = 50285 psi

Figure 5. Von Mises Stress contours for Test Pressure


8/5/2017 Page 6 of 6

Figure 6. Shear Stress Contour on Gimmick

Figure 7. Shear Stress Contour thru Lug center plane

The Von Mises stress contours are shown in Figure 5. The contour upper limit for figure 5 is set to 75,000 psi so that areas of the gimmick and hanger exceeding yield strength are easy to identify. Figures 6 and 7 contain shear stress contours for the gimmick and lug respectively. The contour limits are set for the allowable shear stress values. There are shear planes through both the lugs and the gimmick that exceed allowable for each. Based on these results it can be concluded that this assembly does not meet industry requirements and is not fit for service.

a 4 5 1 c c 3 - omcmech.com · 3) asme bpvc section viii div ii c. description: male stab for...

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