I. Visual Inspection
1. Surface Examination
Casting defects: Cracks/sand holes/laminations
Coating quality: Uniformity (no runs/peeling)
Surface finish: Ra≤3.2μm per ISO 1302
2. Dimensional Verification
| Measurement | Tools | Tolerance |
|---|---|---|
| Body OD/Height | Digital caliper | ±0.5% nominal |
| Flange bolt hole PCD | Coordinate measuring machine | ISO 2768-mK |
II. Pressure Testing
A. Shell Test (Strength)
Medium: Water (compressed air for special valves)
Pressure: 1.5×PN (min 0.3MPa)
Duration: 5-10 minutes
Acceptance: No visible leakage
B. Seat Test (Sealing)
| Valve Type | Test Medium | Pressure | Duration |
|---|---|---|---|
| Liquid service | Water | 1.1×PN | 15 min |
| Gas service | Air/Nitrogen | 1.1×PN | 30 min |
Note: For double-block-and-bleed valves, perform bidirectional seat tests
III. Functional Testing
1. Operation Test
Manual valves: ≤10Nm torque (DN≤100)
Actuated valves:
Full stroke time ≤30s (pneumatic)
Torque switch calibration per IEC 60534
2. Flow Characteristics
Test equipment: Flow coefficient (Cv) test rig
Output: Flow vs. opening percentage curve
IV. Leak Detection
1. Helium Mass Spectrometry
Sensitivity: ≤1×10⁻⁹ Pa·m³/s (for vacuum valves)
Methodology:
Pressurize with 5bar He mixture
Scan with detector probe
2. Bubble Test
Immersion duration: ≥2 minutes
Bubble criteria: ≤3 bubbles/min (ISO 5208 Class A)
V. Material Verification
1. Spectrochemical Analysis
Equipment: Optical emission spectrometer
Standard compliance:
ASTM A216 (WCB)
ASTM A351 (CF8M)
2. Hardness Testing
| Component | Method | Requirement |
|---|---|---|
| Body | Brinell HB | 187-241 (WCB) |
| Stem | Rockwell HRC | ≥35 (17-4PH) |
