Check Valves
Check Valve
Function
Check valves in injection moulding systems prevent backflow of the melt into the screw channels, therefore ensuring complete delivery of the metered melt volume. A check valve consists of a screw tip, a check ring and a seat or adapter ring. Special versions are available including a control ring.
Available Versions:
Wear-resistant check valves: available in high-alloyed tool steels, fully hardened, with hardfaced flights or in powder-metallurgic materials.
Hardfaced Screw Tips
- High wear resistance due to the hardfacing of the contact surface
- Service life several times longer than that of non-hardfaced tips.
Application Fields:
Processing of resin formulations incorporating glass-fibre reinforcing additives or fillers, etc.
Advantages:
The hardfacing provides an extremely resistant contact surface and an optimum material pairing between the screw tip and the check ring. As a result, the check ring moves with minimum friction and wear. Hardfaced screw tips can be supplied as OEM equipment or refurbished on used tips.