gt group logoAs automotive engine manufacturers face ever tighter environmental emission regulations they are imposing stringent requirements on component suppliers for effective product testing.

GT Precision Products, part of the GT Group of companies, are Tier 1 automotive suppliers of exhaust valves for diesel engine vehicles. These include EPM (Exhaust Pressure Modulator) valves which act as exhaust brakes by controlling back pressure into the engine, and EGR (Exhaust Gas Recirculation) valves which reduce emissions by re-circulating exhaust gasses.

To test a new range of valves the company wanted to replace their existing test rigs, which used high volume air pressure to replicate engine operating conditions. This used a large air reservoir and compressor installation which was not only expensive to operate and maintain but also occupied a large area of the manufacturing site that could be used more productively.

Replacement test rigs using a low volume pneumatic system were designed by Tascomp, Billingham, UK in close consultation with GT Precision Products technical department. The mechanical design and assembly of the rigs was carried out by the GT Group with Tascomp developing the PC based control and monitoring system.

Each valve is tested during manufacture. The valve movement is monitored as air is passed through the test piece in a sequence precisely controlled by the system. A range of parameters are tested including stiction of moving components, flap leakage fully closed, quick release test and modulation force.

Prodigy industrial automation software is used to monitor and control the valve test rigs, control each test sequences and record the test data. The software also validates each test, automatically passing or failing each valve tested

A single page “Proof of process” report is created for each product tested, referenced by the part type and serial number. This shows the test header information, a list of alarm/events during the test and a graph of test parameters. This report provides accurate test data and traceability for every valve shipped and allows GT Precision Products to validate the quality of its products for its major automotive customers.

Recipe based control parameters make it easy for GT Group personnel to modify test parameters and create a library of tests to cover the range of products to be tested.

The success of the new system has allowed the decommissioning of the original air reservoir and compressor not only significantly reducing running costs but also freeing up valuable extra space for manufacturing at their Peterlee, UK factory.

Tascomp are the developers of Prodigy industrial automation software which features a range facilities that make it ideal for test automation. Prodigy software is available through a network of authorised resellers.

4 June 2008