What is Leak & Tightness Testing?
Leak testing pressurizes a part with gas (air, nitrogen or helium) and detects pressure loss or tracer gas escape. It is used on fuel lines, valves, cylinders, fuel cells and any sealed component.
It is required for safety-critical parts — fuel systems, gas paths, pressurized enclosures. A missed leak means gas escape, fire risk, or product failure in the field.
Pressure-decay method measures tiny pressure drop over time. Helium mass spectrometry (helium leak test) detects leaks far smaller — down to 10⁻⁹ mbar·L/s — for fuel cells and high-purity systems.
Manual vs Electric vs Air-Driven
Drive methods differ sharply in pressure limit, explosion safety, and automation.
| Drive Method | Pressure Limit | Explosion-Proof | Features |
|---|---|---|---|
| Manual pump | ~100 MPa | ✓ (no electricity) | Cheap / labor-intensive / no automation |
| Electric pump | ~300 MPa | Needs Ex motor | Automated / needs power / heat |
| Air-driven pump | ~600 MPa [TBC] | ✓ (pneumatic) | Safe / auto hold / no power |
For leak testing, air-driven pressurization = safe + precise + repeatable.
SUNCENTER Equipment for This Process
Pressure-Decay Leak Test Bench
Production line, auto pass/fail.
Helium Leak Test System
Fuel cell & high-purity parts, ultra-sensitive.
Air-Driven Gas Booster
Pressure source for test bench.
Process Flow Diagram
Flow subject to technical-dept. confirmation
Prepare
Seal workpiece, connect test port.
Pressurize
Fill with test gas to set pressure.
Stabilize
Wait for temperature to settle.
Measure
Monitor pressure decay over hold time.
Judge
Drop within threshold = pass.
Relief
Vent gas, disconnect.
Typical Parameters
Values per product manual — for reference only.
| Workpiece | Test / Working Pressure | Recommended Model |
|---|---|---|
| Fuel cell plates | 0.1-0.5MPa | Helium system |
| Fuel/brake lines | 0.5-2MPa | Pressure-decay bench |
| Valves & fittings | Per spec [TBC] | Air-driven bench |
Further Reading
Blog system under construction — titles below are planned.
- Pressure-decay vs helium leak test: which to choose?TBC
- How to set leak test pressure and hold timeTBC
- Common false-reject causes in leak testingTBC
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Tell us your working conditions and target pressure — our engineers recommend the right model.