HPHT Flange DesignSince the Winter meeting:• Met four (4) times • Working on Flange Design Methodology (By the winter

meeting we will have a step-by-step description of the Flange Design Methodology to size the flange (based on Eichenberg) and a step-by-step description of the Flange Verification Methodology to create the Capability Charts for 6AF3 (using non-linear FEA).)

• Much of the work since the winter meeting was dedicated to justifying the existing BX gaskets suitability for the HPHT applications

• For the winter meeting we will demonstrate the step-by-step method by designing and verifying the capabilities of an 18-3/4 20K flange

BX 164 Gasket FEA StudyRound Table Discussion

BX Gasket Dimension Comparison with API 6A

Kevin Leaning LTS Energy

Gasket Study Jon Ellens NOV

Review of Eichenberg Calculation Methods

DESIGN REVIEW

1. COMPARE EICHENBERG CALCULATED GASKET AND RING GROOVE GEOMETRIES AGAINST CURRENT API 6BX 10K, 15K & 20K SIZES

2. ESTABLISH A “BASELINE” ANALYTICAL DESIGN CALCULATION WORK SHEET BASED ON EICHENBERG CALCULATION METHODS

3. EVALUATE EICHENBERG FLANGE CALCULATION METHODS AGAINST “ALL” CURRENT API 20K 6BX FLANGE/GASKET GEOMETRIES

4. EVALUATE EICHENBERG FLANGE CALCULATION METHODS USING EICHENBERG 20K FLANGE/20K GASKET GEOMETRIES

5. ESTABLISH EICHENBERG DESIGN FOR 18.3/4” 20K WN FLANGE & GASKET5. SUMMARY OF RESULTS USING EICHENBERG CALCULATION METHODS FOR 20K

FLANGE AND GASKETS

Review of Eichenberg Calculation Methods

BX Gasket Dimension Comparison with API 6A

Review of Eichenberg Calculation Methods

EICHENBERGAPI 2.1/16” 20M BX-152

Review of Eichenberg Calculation Methods

EICHENBERGAPI 18.3/4” 20M 164-E

Review of Eichenberg Calculation Methods

SUMMARY

1. ALL CURRENT API 20K 6BX FLANGE GEOMETRIES MEET EICHENBERG FLANGE CALCULATION METHODS. EXCEPT FOR BX-RINGS AND RING GROOVES.

2. API 20K 6BX FLANGES WILL MEET EICHENBERG FLANGE CALCULATION METHODS IF USING EICHENBERG CALCULATED RINGS BX-E.

3. EICHENBERG METHODS CAN BE USED TO DESIGN AN API 18.3/4” 20K BX-164-E FLANGE AND GASKET.

4. THE BX-164-E WILL EFFECTIVELY SEAL AGAINST 30K HYDROTEST PRESSURE, AND WOULD PERFORM BETTER THAN THE EXISTING BX-164 GASKET ORIGIONALLY DESIGNED FOR 10K SERVICE.

BX-164 Gasket StudyResidual Contact Force

Evaluated with FEA

Mesh

• 43,198 nodes

• 37,774 elements (all first order hex)

• 1/40 Symmetry Applied

Loading

Wellbore Pressure Application

Pressure End Load

Rigid surface w/ contact enforced for flange

Loading Application

1. Preload bolts

– 40 ksi preload

2. Fix bolt length

– Standard Abaqus procedure for preloaded bolts

3. Apply wellbore pressure

– 20, 30, 40 ksi (each pressure run as separate analysis)

4. Remove wellbore pressure

Materials

• Gasket– Elastic-Plastic: Two Gaskets Evaluated

• 30/75 ksi YS/TS• 50/90 ksi YS/TS

• Flange and Bolts– Mostly Linear-Elastic (see image, blue)

• Flange groove area– Elastic-Plastic in some analyses to evaluate plastic strain upon

preload (75/95 ksi YS/TS)

Gasket Model

Minimum Material Condition - Evaluated

vsNominal

0

10000

20000

30000

40000

50000

60000

70000

80000

15 20 25 30 35 40

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Wellbore Pressure (applied then relieved, ksi)

Residual Normal Contact Force vs Wellbore Pressure

30k Gasket

50k Gasket

30k Gasket - EP flange

50k Gasket - EP Flange

Residual Normal Contact Force –Outer Diameter

Preload Comparison30 ksi Gasket 50 ksi Gasket

Flange groove area modeled as elastic-plastic (75/95 ksi)

HPHT Flange Flowchart – Gasket Selection/Design

Same size and lower pressure BX gasket available?

Evaluate using existing gasket

Verify using 3D FEA –Acceptable residual contact force study?

Would increased strength gasket be acceptable (50 ksi YS, verified with 3D FEA residual contact force study)?

Create new gasket / groove geometry (Eichenberg or alternative methods)

Continue with HPHT flange design and verification

Yes

No

Yes

No

Yes

No