API 6A Gate Valve Stem Packing Seals Test-jst-seals.com

API 6A Gate Valve Stem Packing Seals Test

July 09. 2021

I Test Purpose

To verify the pressure cycling performance of the gate valve stem packing seals at 15000PSI, -50~350℉.

II Product and fixture

1. Product structure

The seals include 1 of A ring, 1 of spring, 1 of U ring, 1 of B ring, and 1 of C ring, see fig. 1:

2. Material :

1-PTFE+13% Carbon fiber+2%Graphite (PC007)

2-PTFE+13% Carbon fiber+2%Graphite (PC007)

3-Elgiloy Golden

4-PTFE+13% Carbon fiber+2%Graphite (PC007)

5-PEEK (PK002)

3. Product picture see Fig. 2:

4. Fixture structure

2 sets of same products were installed and tested simultaneously as per the seals structure and testing pressure. See testing fixture in Fig.3:

III Test Standards

Refer to API 6A, 20th Edition, Errata 1 thru 7, Addendum 1 thru 3, Annex F PR2. No temperature or pressure cycling.

IV Acceptance standards

During each pressure hold period, there should be no visible leakage; or the pressure rate of change should be no more than 5% of the testing pressure or 3.45MPa/h(500psi/h), whichever is less during hold period. Both results are acceptable.

V Test conclusion

1. The pressure cycle performance PR2 test of gate valve stem packing seals is conducted under -50F~350°F, working pressure 15000PSI. The test data are shown above, which meets the test acceptance criteria, the test passed successfully.

2. The fixture was disassembled after test, the appearance of the seal was good without damage, there was lip interference. The seals after testing still had a sealing function. See the fixture disassembled: