1. Carry Over From API SC6 Winter Meeting API Spec 6A Tensile Test Requirements
Tim Haeberle
30 June 2011

2. Contents
1. Clarification Of Spec Reference For Standard Size Tensile Test Specimens
2. Clarification Of Tensile Test Acceptance Criteria For Mandrel Tubing Hangers And Mandrel Casing Hangers

3. Spec Reference For Tensile Test Specimens

4. Background CURRENT WORDING
PSL 2 to 4 tensile testing (for mandrel tubing hangers and casing hangers)
“b) test method:
Perform tensile tests at room temperature in accordance with the procedures specified in ISO or ASTM A370.
Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the manufacturer’s specified requirements.”
PSL 2 to 4 tensile testing (for bodies, bonnets, and end and outlet connections)
Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the applicable requirements of Table 6.”

5. Background CURRENT WORDING Section 5.6.4.1 (for TC’s for PSL 1)
Paragraph 5 - “Standard-sized, 12,5 mm (0,500 in) diameter tensile specimens shall be used to qualify carbon, low-alloy and stainless steels, unless the physical configuration of the TC prevents their use. In this case, the standard sub-size specimens referenced in ASTM A370 may be used. Either standard 12,7 mm (0,500 in) or standard sub-size specimens (see ASTM A370) may be used to qualify CRA materials.”
Section (for QTC’s for PSL 2-4)
Paragraph 6 - “Standard-sized, 12,5 mm (0,500 in) diameter tensile specimens shall be used, unless the physical configuration of the QTC prevents their use. In this case, the standard sub-size specimens referenced in ASTM A370 may be used.”
PROBLEM:
These paragraphs do not state that the “standard” specimens are ASTM A370 standard-sized specimens, although they do state that when sub-size specimens are used, they shall be the ASTM A370 standard sub-size specimens. This leaves open the use of ISO standard specimens.

6. Need to fix in both ISO & API versions
The Solution
PROPOSED REVISIONS:
Section
Paragraph 5 - “ASTM A370 standard-sized, 12,5 mm (0,500 in) diameter tensile specimens shall be used to qualify carbon, low-alloy and stainless steels, unless the physical configuration of the TC prevents their use. In this case, the standard sub-size specimens referenced in ASTM A370 may be used. Either standard 12,5 mm (0,500 in) or standard sub-size specimens (see ASTM A370) may be used to qualify CRA materials.”
Section
Paragraph 6 - “ASTM A370 standard-sized, 12,5 mm (0,500 in) diameter tensile specimens shall be used, unless the physical configuration of the QTC prevents their use. In this case, the standard sub-size specimens referenced in ASTM A370 may be used.”
Need to fix in both ISO & API versions

7. The Solution JUSTIFICATION:
“ASTM A370” needs to be added to clarify that the only specimen sizes currently permitted are the ASTM A370 specimen sizes.
ISO includes different size specimens that have a higher gage length to diameter ratio.
The longer relative gage length of the ISO specimens can result in failure to meet the API 6A specified elongation acceptance criteria.
The use of ASTM A370 specimen sizes meets ISO , since ISO , section 6.1.1, paragraphs 7 and 8 state:
“The dimensional tolerances of the test pieces shall be in accordance with the Annexes B to E (see 6.2).”
Other test pieces such as those specified in relevant product standards or national standards may be used by agreement with the customer, e.g. ISO 3183 [1] (API 5L), ISO [2] (API 5CT), ASTM A370 [6], ASTM E8M [7], DIN [10], IACS W2 [13], and JIS Z2201 [14]”.
ASTM A370 specimen sizes are routinely used in the US and Europe.

8. ISO 6892-1 Circular Test Specimens

9. API CSOEM SR3 Form
Form ready for submittal
No money requested

10. API Ballot
Form ready for submittal

11. Tensile Test Acceptance Criteria For Mandrel Tubing Hangers And Casing Hangers

12. Background CURRENT WORDING
PSL 2 to 4 tensile testing (for mandrel tubing hangers and casing hangers)
“b) test method:
Perform tensile tests at room temperature in accordance with the procedures specified in ISO or ASTM A370.
Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the manufacturer’s specified requirements.”
PSL 2 to 4 tensile testing (for bodies, bonnets, and end and outlet connections)
Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the applicable requirements of Table 6.”
API 6A Table 6, column 2 (for bodies, bonnets, and end and outlet connections)
“0,2% offset yield strength”.

13. Need to fix in both ISO & API versions
Background
PROBLEM:
The yield strength acceptance criteria for bodies, bonnets, and end and outlet connections is limited to the 0,2% offset method yield strength values in Table 6. This is good!
However, for mandrel hangers it is up to the manufacturer to specify not only the yield strength in MPa (psi), but also the method of determining the yield strength.
Unfortunately, if the manufacturer does not specify the method of determining the yield strength, methods other than the 0,2% offset method may be used, and these may give higher or lower values than would be obtained if the 0,2% offset method were used.
Need to fix in both ISO & API versions

14. Need to fix in both ISO & API versions
The Solution
PROPOSED REVISION:
PSL 2 to 4 tensile testing (for mandrel tubing hangers and casing hangers)
“b) test method:
Perform tensile tests at room temperature in accordance with the procedures specified in ISO or ASTM A370.
Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the manufacturer’s specified requirements. The 0,2% offset method shall be used for determination of the yield strength”.
JUSTIFICATION:
A standardized method of determining the yield strength needs to be used for mandrel casing and tubing hangers.
Need to fix in both ISO & API versions

15. API Ballot
Form ready for submittal

16. End Of Presentation