Test Application from TQC
Speed Leak Testing of Welded Pipe Fittings
using Air & Helium as Test Mediums
TQC have supplied a suite of 3 automatic leak testing
machines that are conveyor fed.
The first two machines were designed to 100% leak
test numerous variants of welded metal T-pieces, elbows, reducers
and adapters used in the water, gas and construction industries.
The leak test specification meant that the parts needed to be water
The customer then asked TQC to develop a machine to
meet the more stringent requirements of testing parts to ensure
they are gas tight, and still meet the high production throughputs.
TQC met these objectives by integrating helium leak testing technology
into the same handling concept of the first two machines.
features of each leak test machine are :
- Rotary indexing machine
- Automated load / unload
- Twin chamber with interchangable tooling for multiple variants
- Combination leak test using high pressure internally and high
- High speed leak test
- Water and Gas tight leak specification met using air or helium
as test medium
- Testing to leak test threshold of 1mm3/sec (1x10-6 mbar.l.sec-1)
A twin gripper pick and place system was used to load
parts from a conveyor pallet to the test fixture and then remove
the parts after testing. Twin chamber test fixtures mounted on a
rotating table were used to allow automated load and unload whilst
meeting the high throughput.
Leak test instruments tested each component. Both
internal high pressure and external vacuum was used to stress the
part under test correctly and to provide a short cycle time leak
up of tooling, leak test chambers etc.
The test process required the part to be evacuated,
low pressure helium inserted for a gross leak test, then high pressure
helium for a fine leak. On completion, the helium was removed from
the part and the part stabilised with air.
The system included monitoring of any leaking helium
this allows fast testing and minimises helium loss by part leakage.
Varian mass spectrometers have been integrated to
monitor the helium gas, with a trigger point used to indicate a
leaking part. The leak test threshold that was set by the customer
was 1mm3/sec (1 x 10-6 mbar.l.sec-1).
A helium reuse system was integrated into the test
machine, this automatically monitored the gas quality and purged
the system once the helium was below a set concentration. By including
the recovery system typically 50 -100 parts (depending on internal
volume) can be tested before the helium needs to be replaced.
Leak Test Machine
If you are currently considering a high speed
or complex leak test application, or production automation call
us and we will be happy to offer our professional advice & visit
you at your site.