They utilise highly aggressive Oemeta HF/DU hydraulic fluids, working at operating temperatures of 250°C, and are used to retain large hot dies in exact positions on forging machines, and also secure hot moulds in injection moulding equipment. The clamping products are designed to withstand pressures of up to 400 bar at maximum temperatures. Any leakages of hydraulic fluid from the multiple pistons utilised to apply the clamping forces of 25 to 1250 kN could not be accepted.
By switching to the Kalrez Spectrum 7075 sealing parts for their hydraulic pumps range, the manufacturer could offer a long-term resistance to aggressive fluids, as well as operating temperatures of 250°C, coupled with increased reliability for their systems, while also achieving cost savings. Previously, other sealing solutions needed replacements due to seal failures after only a few months of operation. Since refitting with the Kalrez seals, the clamping systems have operated without problems or seal replacements for over 18 months. The company service intervals for their pressure cylinders have been considerably extended, providing cost savings and increased overall reliability for their clamping system. It has also allowed the company to offer new areas of application for their products to their existing and new users.
The sealing products in the DuPont Performance Elastomers range are available in the UK from Dichtomatik Ltd, an authorised distributor. The Kalrez Spectrum 7075 product offers enhanced physical performance properties including very low compression set and maximum service temperatures up to 327°C. This makes it an ideal choice for mechanical seals, valves, flanges and other demanding chemical and hydro-carbon processing applications. It is a carbon black filled compound designed for use as O-rings or custom sealing components combining long-term performance, low compression set and longer service life.