Comprehensive Guide to Industrial Valve Pressure Testing Methods

Industrial valves play a critical role in controlling the flow of fluids and gases in various industries, from petrochemical plants to water treatment facilities. Ensuring their reliability and safety is essential. One key aspect of this assurance process is valve pressure testing, which includes both strength testing and sealing performance testing.

This article outlines the pressure testing methods for various types of industrial valves, helping engineers and technicians understand standard practices and ensure optimal system performance.

Valves

Why Valve Pressure Testing Matters?

Although valves generally do not undergo strength tests before regular use, those that have been repaired or show signs of corrosion must be tested for structural integrity. According to industrial regulations:

Low-pressure valves: 20% are tested; if one fails, 100% must be tested.

Medium- and high-pressure valves: 100% inspection is mandatory.

Test mediums: Water, oil, air, steam, nitrogen, and other suitable substances are commonly used.

Valve Testing Methods by Type

1.Ball Valve Testing

Strength Test: Conducted with the ball in a half-open position.

Sealing Test:

Floating Ball Valves: Apply pressure to one side with the other sealed; rotate and check for leakage.

Trunnion Mounted Ball Valves: Test both sides using pressure gauges (accuracy 0.5–1 grade), ensuring no pressure drop.

Three-Way Ball Valves: Must be tested in all flow positions.

2.Check Valve Testing

Strength Test: Pressure is introduced from the inlet with the outlet sealed.

Sealing Test: Pressure is introduced from the outlet; inspect inlet for leakage.

3.Pressure Relief Valve (PRV) Testing

Strength Test: Conducted before or after assembly, using air at 1.5× maximum service pressure.

Sealing Test:

Air/water: At 1.1× nominal pressure.

Steam: At maximum service pressure.

The valve must adjust outlet pressure smoothly without sticking.

butterfly valves

4.Butterfly Valve Testing

Strength Test: Same method as globe valves.

Sealing Test: Test pressure from inlet side with disc open; check disc and body seals after closure.

5.Plug Valve Testing

Strength Test: Rotate plug to all positions; check for leakage.

Sealing Test: Pressurize from one end, rotate and test each position; apply a non-acidic lubricant if needed.

6.Diaphragm Valve Testing

Strength Test: Fully open disc, seal one side, apply pressure and check for leakage.

Sealing Test: Reduce pressure, close valve, open opposite end, and inspect.

7.Globe & Throttle Valve Testing

Strength Test: With the valve fully open, pressurize and check body and cover.

Sealing Test: Introduce pressure from beneath the disc; close the disc and check for leakage at the outlet.

gate valve

8.Gate Valve Testing

Strength Test: Same as globe valve.

Sealing Test:

Mid-body Test: Apply pressure with gate closed and check both sides for leaks.

End Test: Apply pressure, then open one end to check seal. Both directions should be tested.

9.Safety Valve Testing

Strength Test: Water is used to test both upper and lower valve body chambers.

Sealing & Set Pressure Test:

Medium: Steam, air, water, or nitrogen depending on the application.

Criteria: Two test cycles minimum, with no leakage allowed under nominal pressure.

Final Thoughts

Proper valve testing ensures the longevity and safety of your fluid control systems. Whether you’re working with ball valves, gate valves, check valves, or safety valves, following correct test procedures can prevent failures, leaks, and safety hazards. At Haihao Group, we provide not only high-quality valves and fittings but also expert guidance in testing and inspection procedures, ensuring our clients receive the most reliable piping solutions available.

Need custom valve solutions or test consulting?

Contact Haihao Group for comprehensive support on industrial valves, fittings, and piping systems. Email:sales@haihaogroup.com