Crane Electronics Tightens Up On Cost-Effective Quality

MAHLE Powertrain has relied on Crane Electronics’ torque control products for over a decade. Due to the increased level of testing required by MAHLE and their customers, they have decided to upgrade their equipment with the latest generation of Crane products. Dave Burton, Production Engineer, at the Wellingborough production plant in the UK explains: “We assemble engines and, depending on the project, typically checking one in 50 engines per shift basis to ensure high-quality tightening of nuts, bolts and fasteners.” Delivering the correct level of torque is crucial in the automotive industry: too little and joints may rattle and loosen with implicit safety implications. Alternatively, over tightening can mean fixings are taken past their yield point, which is just as dangerous, leading to early failure of the bolted joint.

byNews Desk

April 10, 2008

MAHLE has now added two new Crane products to its quality systems, the ProWrench Opta and the Torquestar Opta. The ProWrench Opta is a digital torque wrench which is compact, portable and highly adaptable. Not just an audit tool, it can be used for low volume tightening or to rectify joints where the torque is found to be incorrect. A range of attachments can be fitted to suit each tightening application. The electronic wrench is point of load insensitive which means results will even be reliable when it is being used at odd angles.

“With the ProWrench Opta we can check all the bolts on a particular engine in one go by programming it with a sequence of appropriate values (Jobs). This represents an invaluable time-saving feature,” adds Mr. Burton.

For high-volume tightening MAHLE Powertrain is using air and hand wrenches. As these tools are not networked, their capability has to be checked and documented as part of an auditing strategy. MAHLE Powertrain uses a Mobile Tool Testing Station (MTTS) from Crane for this purpose. The heart of this system is a new TorqueStar Opta data collector and incorporates multiple stationary transducers, joint kits, a printer and a tool reaction post. As the system is on trolley it can be easily be moved around the production area.