In order to maintain the high quality level, in South Indian Bangalore, the newly developed plastic components also undergo extensive quality checks. Different coordinate measuring machines are available for dimensional checking of numerous prototypes usually involving plastic housings for electro mechanic products. In order to be able to position these difficult geometric parts correctly with regard to quality checking aspects, special fixtures are required. Senior Engineer Ms. Shashikala Ramakrishnan is head of the Metrology team since 2006. Based on her extensive experience in quality assurance, she focussed on using a modular fixturing system for holding the irregularly formed small parts right from the beginning. Since she had already had very positive experience with the high-tensile aluminium components in her previous job, using anything other than the accurate aluminium parts for her new position was out of question. The range of parts to be checked is very big, only very rarely is a part repeated. That means a special fixture must be provided for each individual part. Using conventional dedicated measuring fixtures for this application would be completely inconceivable. The time required for manufacturing conventional fixtures, would slow down the entire process immensely. At the same time each further prototype would cause additional costs. Using a modular system makes the user independent. Fixtures are assembled at any time, no arrangements with fixture builders are required.
Alufix fixturing system from Witte consists of many highly accurate components, which can all be assembled together. Apart from the high accuracy of the parts, milled out of solid material, the long life of the individual components is a further advantage. The Alufix components can be used over many years. "Some users have been working for more than 15 years with the same components. They are absolutely wear resistant. Nevertheless, in order to adapt to changing requirements, new elements are constantly being developed. The basic principle remains consistent, so that new elements are compatible to all existing ones ", explained Stefan Roeding, Managing Director of Witte Far East PTE Ltd., Singapore.
Mr. Venkatesh of Sandeep Engineers, Witte partners in Bangalore, added "Once an investment in basic equipment has taken place, a customer never needs to worry about future fixture costs. Because on the one hand the flexibility of Alufix allows us to build all kinds of fixtures very quickly, and on the other hand Alufix parts are so strong and hardwearing that costs for replacements can be excluded from the beginning.”
Alufix is available as a complete fixture, basic set or as individual components. Based on her previous experience Ms. Shashikala Ramakrishnan chose a range of Alufix components most suited for her applications. Since her parts are almost exclusively made of plastic the measuring fixtures must do justice to demands made by such material. Plastic parts need special treatment. The material is often soft and fragile; the parts are unstable and this leads to the main problem of distortion. That means in order to determine correct part data the workpieces cannot be clamped but only supported. No pressure may be exerted on the workpiece, otherwise it will temporarily deform and lead to false measuring results.
Schneider Electric build new measuring fixtures almost daily with their existing Alufix components. After use fixtures are quickly dismantled again and the components are on hand to rebuild a new fixture for the next prototype.