Leak Test Examples
Automotive
The quality demands of world class manufacturers are very high, particularly for the automotive industry. Leaks being found, after a component has been assembled into a vehicle, are simply not acceptable to the motor manufacturers. The cost of poor quality in warranty costs, and potentially the loss of customers, is enormous. 100% leak testing of products as part of the production process enables quality to be guaranteed.
Applications for automotive component manufacturers are diverse, including all air conditioning parts, all fuel system parts (to avoid emissions), air suspension systems, suspension air spring, engine, gear box, brake systems, cooling systems etc.
All pressurised automotive components need to be tested for leaks. For many of these components the leak rate limits are too tight for traditional pressure decay methods. Helium leak testing guarantees the leak tightness of the whole component sent on to your supplier.
Alloy wheels, fuel tanks, filler pipes, fuel lines, fuel rails, fuel vapour charcoal canisters, condensers, evaporators, radiators, charge air coolers, pipes, air suspension, air bags
Typical Applications & Specifications
Alloy Wheels – Fuel lines – Fuel rails – Charcoal canisters – Evaporators – Condensers – Radiators – Air suspension – Air Bags - Fuel tanks – Filler pipes – Flanges
Fuel tanks - based on a 15 micron hole, and are equivalent to a helium leak rate of around 5.0 e-5 to 5.0 e-4mbar·l/s
Filler pipes – based on a 15 micron hole, and are equivalent to a helium leak rate of around 5.0 e-5 mbar·l/s
Flanges - typically around 2.0 x 10-6 mbar·l/s [the flanges then becoming part of the fuel tank]
Helium Leak Testing
- Tailored to suit production TAKT times
- Saves on Warranty Costs
- Enables Quality to be achieved and maintained
- Compliance with current laws & adaptability for future changes
HVAC / Refrigeration / REFRIGERANT LEAK
Refrigerant gases are harmful to the environment, so stringent acceptable losses are applied, typically equivalent to a car tyre going flat in 40+ years!
Typical Applications & Specifications
Heat exchangers - Refrigerated trucks - Heat pumps – Refrigerators - Air-conditioning units - Aircraft cooling systems - Condensers – Evaporators - Compressors (scroll or hermetically sealed) - all HVAC components
Condensers – 0.1 to 3 grams / annum of gas, equivalent to around 2.0 e-5 mbar·l/s of helium
Evaporators – 0.5 to 3 grams / annum of gas, equivalent to around 2.0 e-5 mbar·l/s of helium
Compressors – 0.1 to 3 grams / annum of gas, equivalent to around 2.0 e-5 mbar·l/s of helium
Aerospace cooling systems < 0.2 micron hole, equivalent to < 1.0 e-6 mbar·l/s of helium
Helium Leak Testing
- Tailored to suit production TAKT times
- Saves on Warranty Costs
- Enables quality to be achieved and maintained
- Compliance with current laws & adaptability for future changes
Fire Extinguishers
Why Leak Test Fire Extinguishers?
'The leak test requirement for stored pressure and self-propelled types should be sufficiently sensitive to ensure that the fire extinguisher remain operable for at least one year'
- NFPA portable leak test standard
The leak rate is incredibly small especially for small extinguishers – the equivalent leak on a car tyre could take more than 250 years to go flat! If the stored pressure has leaked away it won't work, this can have disastrous consequences for lives and property!
It is not possible to use helium sniffing equipment as leak rates are way below atmospheric levels. For a simple air under water test, it would take more than 6 minutes for a single bubble to form
100% leak testing with a hard vacuum tracer gas system method guarantees leak tightness. Helium leak testing (by including a 5% helium mix inside the propellant gas) is a proven technique and is used widely.
Helium Leak Testing
- Ensures safety to customers
- Demonstrates due care has been taken to ensure the product is safe
- Saves on Warranty Costs
- Enables Quality to be achieved and maintained
- Compliance with current laws & adaptability for future changes
Gas Meters
Domestic gas meters must be tested during the manufacturing process for both their operation and leak tightness.
Leak rate levels typically equivalent to a leak rate of 1.0 e-6 mbar·l/s using helium
Helium Leak Testing
- Ensures safety to customers
- Demonstrates due care has been taken to ensure the product is safe
- Saves on Warranty Costs
- Enables Quality to be achieved and maintained
- Compliance with current laws & adaptability for future changes
SF6 Switchgear
Leak testing is of paramount importance to ensure safe operation of the switchgear during it's lifetime. 'Vacuum switchgear' must maintain their vacuum in order to prevent arcing within the switch.
Likewise 'gas insulated switchgear' must maintain their pressure level to prevent arcing when the contacts open. Sulphur-hexafluoride (SF6) is used due to it's dielectric properties. However, SF6 is a most potent greenhouse gas so cannot be released into the atmosphere. Strict control is maintained over it's usage, with every gram accounted for.
Leak rates are specified at 1% volumetric loss per annum (IEC 60694), equivalent to helium leak rates in the range of 1.0e-6 / 1.0e-7 mbar·l/s
Helium Leak Testing
- Ensures safety to customers
- Demonstrates due care has been taken to ensure the product is safe
- Saves on Warranty Costs
- Enables Quality to be achieved and maintained
- Compliance with current laws & adaptability for future changes
