Utilizing strain transducers for greater accuracy in forging

One of the world's largest automotive component suppliers, Hirschvogel Automotive Components, based in Pinghu, China, is utilizing HBM’s SLB strain transducer and MP55DP amplifier system to monitor forging forces for improved quality. Forging is used in manufacturing to shape metal through localized compressive forces. It is carried out on a heavy-duty forging machine in which a cam mechanism transfers the rotational movement of an electric motor into the linear reciprocating motion of the hammer or so-called slide block. High forces are needed during forging and the force applied to a work piece may exceed the nominal force of the forging machine. The working force can reach several MN: the recorded world maximum force was 800 MN. This makes forging a particularly dangerous activity both to the machine and to personnel working in the area.

The HBM solution

Hirschvogel Pinghu has fitted two SLB700A transducers on each of the support columns of their forging machine. This means that parallel signals are created that are then amplified and conditioned by HBM’s MP55DP single channel amplifier and transferred to the controlling PLC through Profibus DP without any accuracy loss. The whole measuring system is calibrated with lifting jack. HBM’s SLB700A strain transducer is intended for applications where high forces are to be measured. Fitting two SLB700A strain transducers in parallel on opposite sides of the test piece can compensate for bending effects on work pieces. The SLB700A is designed with compensating elements for adapting to the different steel types commonly used in mechanical engineering and features a high degree of protection. The MP55DP is a single-channel, 4.8 kHz carrier frequency amplifier with Profibus interfaces. It is part of HBM’s PME amplifier system and is designed to complement the SLB700A by providing a self-sustained monitoring unit for all industry requirements. The complete system features a CAN or Profibus interface for easy integration into automation systems. HBM is providing leading technology solutions for manufacturers across China and has supplied a similar solution to Schuler China, the technological and global market leader in metal forming.

Special features of HBM’s solution

• Easily monitors strain in statically and dynamically loaded units
• Can be simply bolted into place
• Made of stainless steel to provide protection from environmental impact
• Cost effective
• Utilizing HBM’s PME amplifier system with its Profibus interface facilitates integration into automation systems.