Hydrostatic Testing Equipment plays a critical role in verifying the integrity of pipes, valves, and other pressurized components before commissioning or during routine inspections. A properly conducted hydrostatic pressure test ensures that the system can withstand expected operating conditions without leakage or failure. However, in actual field operations, many users unknowingly make avoidable mistakes that can compromise test results, lead to unsafe conditions, or result in costly delays.
In this article, we’ll walk you through the five most common mistakes encountered during hydrostatic pressure testing and explain how to avoid them. For optimal accuracy and test efficiency, it is equally important to choose a reliable testing system. Below is one of our recommended configurations, widely used by professional labs and industrial contractors:
🔧 Product Showcase (Embedded in standard layout)
❌ Mistake 1: Pressurizing Without Removing Air Bubbles
Residual air trapped inside the pipeline or system can severely affect test accuracy. Since air is compressible, it may cause fluctuating readings or even false pressure spikes.
Recommended Practices:
- Slowly fill the system with water and open air release valves multiple times.
- Tilt or vibrate the pipeline slightly to help trapped air escape.
- Use transparent observation sections to verify full water fill before testing.
❌ Mistake 2: Ignoring Temperature Effects on Pressure Readings
Water expands with temperature rise and contracts when cooled. Testing in extreme temperatures without compensation leads to misleading pressure data or unexpected test failures.
Recommended Practices:
- Conduct tests in a controlled environment (ideally 20°C–25°C).
- Use temperature-controlled water tanks or preheated water in cold conditions.
- Document water temperature and adjust pressure limits if needed.
❌ Mistake 3: Using Mismatched Pressure Gauges or Sensors
Operators sometimes use pressure gauges that are either uncalibrated, outdated, or not rated for the pressure range being tested. This compromises both accuracy and safety.
Recommended Practices:
- Select pressure gauges rated at 1.5 to 2 times the test pressure.
- Recalibrate all sensors at least every 6 months.
- Avoid using gauges with cracked dials, sticky needles, or unclear graduations.
❌ Mistake 4: Rushing the Pressurization and Skipping Hold Time
Rapid pressurization increases the risk of localized stress or instant failure. Inadequate hold time may also miss slow leaks or material creep under sustained pressure.
Recommended Practices:
- Increase pressure slowly and evenly (e.g., 0.2 MPa/min or less).
- Maintain test pressure for at least 30 minutes (or 60+ minutes for plastic pipes).
- Monitor pressure drop during hold and restart the test if deviation exceeds ±5%.
❌ Mistake 5: Overlooking the Integrity of the Test Setup
Leaks often occur not from the test object, but from poorly sealed test setups such as hose joints, flanges, or quick connectors—leading to misdiagnosis or safety issues.
Recommended Practices:
- Perform a «zero-pressure leak check» on the test setup before each test.
- Use proper O-rings, sealing tapes, or gasket materials.
- Retighten connections before applying full pressure and check for seepage.
✅ Pre-Test Checklist: 5 Things to Confirm Before You Begin
- ✅ Test object is completely filled with water and all air has been vented
- ✅ All joints, flanges, valves, and caps are sealed and tightened
- ✅ Gauges and sensors are calibrated and properly rated
- ✅ Testing environment temperature is within standard limits
- ✅ Pressurization and hold time comply with required test standards
📘 Reference Standards and Guidelines
To ensure full compliance and test integrity, refer to the following internationally recognized standards:
- 🔗 ASTM F2164 – Standard Practice for Field Leak Testing of PE Piping Systems
- 🔗 ISO 1167 – Thermoplastics Pipes for the Conveyance of Fluids – Resistance to Internal Pressure
- 🔗 ASME B31.3 – Process Piping Requirements for Pressure Testing
This accessory ensures constant water temperature during hydrostatic testing, minimizing test errors caused by thermal expansion or contraction. Essential for long-duration pressure tests and high-accuracy environments.
🎯 Need Reliable Hydrostatic Testing Equipment?
Looking for a dependable solution to improve your test process? Explore our recommended equipment below: