Mould cavity pressure can be measured without leaving surface marks on the moulding by measuring the strain on the mould induced by the mould pressure.

Kistler has solved the problem of measuring mould cavity pressure without leaving surface marks on the finished product by measuring the strain on the mould induced by the mould pressure, rather than directly using a sensor on the interior face of the cavity. As the sensors are placed behind the wall of the cavity in the mould or die, the interior of the cavity is left smooth. An added benefit is that the sensors do not influence the temperature field at the mould surface so eliminating another possible cause of surface imperfection.

Although it is recognised that monitoring and control of cavity pressure during the moulding cycle is essential to minimising defects, this has been impossible in the past when surface marks on the moulded part could not be accepted.

The introduction of the new Kistler indirect pressure monitoring technique now allows precision moulded parts, such as lenses, light guides and automotive mouldings with Class A finishes, to be produced more reliably using mould pressure monitoring without surface marking.

* About Kistler Instruments - established in Wintherthur (Switzerland) in 1957, Kistler is represented in over 50 countries and has subsidiaries in Germany, France, Italy, UK, Japan, USA, China, Korea and Singapore.

With a staff of more than 800, the Kistler Group is one of the world's leading providers of dynamic measuring instrumentation.

The Kistler Group achieved turnover of SFR 160 million in the 2005 financial year.

Kistler's core competence is the development, production and use of sensors for measuring pressure, force and acceleration.

Kistler's know-how and electronic systems can be used to prepare measuring signals for use in analyzing physical processes, controlling and optimizing industrial processes, improving product quality in manufacturing and improving performance in sports and rehabilitation.

Kistler offers a comprehensive range of sensors and systems for engine development, automotive engineering, plastics and metal processing, installation technology and biomechanics.

Heavy investment in research and development, 15% of staff worldwide are engaged in research and development, has generated a number of innovations using piezoelectric, piezoresistive and capacitive techniques to provide solutions to numerous force, pressure and acceleration measuring problems.

These innovations include the world's first commercial quartz sensor, two-wire constant current technology to integrate sensors with microelectronic circuitry, high-temperature pressure sensors for use up to 400 deg C and three-component force measuring sensors.