The Four-Stage Zero-Defect Testing Protocol
TSV adheres strictly to API 598 and API 6D testing codes. All testing media (treated water with corrosion inhibitors and chloride content < 30 ppm for stainless steels) is continuously monitored.
Hydrostatic Shell Test
The valve is positioned partially open. Hydraulic pressure is increased to 150% of Cold Working Pressure (CWP). Held for the mandatory duration without any visible structural deformation, sweating, or joint weeping.
- No packing leakage permitted
- No flange gasket weeping allowed
- Chloride-controlled test water
High-Pressure Seat Test
The valve is closed. 110% of rated working pressure is applied alternately to upstream and downstream ports while measuring any seat bypass on the opposite port or through the body bleed port.
- Zero drops allowed for soft-seated valves
- API 598 Rate A compliant
- Metal-seated per ISO 5208 Rate B/C
Low-Pressure Air Seat Test
5.5 to 7 bar (80 psig) dry clean compressed air or inert nitrogen is injected into the closed valve with seat boundaries monitored under water or with calibrated soap bubble meters.
- Zero bubbles per minute for soft seats
- Detects microscopic surface scratches
- Essential for gas pipeline certification
DBB & Cavity Relief Verification
For API 6D trunnion ball valves, both seats are energized under full differential pressure while opening the body cavity vent plug to confirm independent bi-directional seal integrity and self-relieving pressure relief.
- Double Block and Bleed verified
- Cavity automatic relief < 1.33 × rating
- Full traceability to test bench log
Heavy-Duty Multi-Axis Hydraulic Clamping Test Benches
TSV operates specialized hydrostatic and gas testing stations capable of clamping valves from NPS 1/2" up to NPS 60" with hydraulic pressures up to 15,000 psig (1034 bar).
- Digital Chart Recorder: Dual calibrated pressure sensors generate tamper-proof digital test certificates.
- Automated Clamping: Prevents artificial external stress on the valve body during seat leakage trials.
- Third-Party Witness: Dedicated inspection room with video feed and remote live-streaming FAT capability.
Minimum Holding Duration Matrix (API 598 vs API 6D)
| Nominal Valve Size (NPS) | Shell Test (API 598) | Shell Test (API 6D) | High-Pressure Seat Test | Air Seat Test (API 598) |
|---|---|---|---|---|
| NPS ≤ 2" (DN 50) | 15 seconds | 2 minutes | 2 minutes | 15 seconds |
| 2-1/2" ≤ NPS ≤ 4" (DN 65 - 100) | 60 seconds | 2 minutes | 2 minutes | 60 seconds |
| 6" ≤ NPS ≤ 10" (DN 150 - 250) | 120 seconds | 5 minutes | 5 minutes | 120 seconds |
| 12" ≤ NPS ≤ 18" (DN 300 - 450) | 300 seconds | 15 minutes | 5 minutes | 120 seconds |
| NPS ≥ 20" (DN 500+) | 300 seconds | 30 minutes | 5 minutes | 120 seconds |
Request Official Certifications, Test Records, or Audit Review
Need certified copies of API 6D licenses, OXY vendor approval records, hydrostatic test charts, or an EN 10204 3.1/3.2 MTR sample? Submit your specification or inquiry below. Our quality engineering team responds within 24 hours.