STELEX ZR ceramic foam filters are manufactured from Zirconia. They have been specially developed for the filtration of molten steel and are suitable for castings temperatures up to 1680C. Increasingly, due to their combination of high mechanical strength and superior filtration capacity, STELEX ZR filters are applied on large ductile and grey iron castings. STELEX ZR filters minimise molten metal turbulence within the mould cavity, helping to prevent reoxidation. Using STELEX ZR filters in your gating systems will help to prevent non-metalic materials reaching the mould cavity. This reduces the need for additional finishing such as the removal and repair of slag inclusions, shortening the total processing time.

Filtration effectiveness largely depends upon the correct application of STELEX ZR filters. When applying filters we always recommend using STELEX filter prints which have been
developed in close co-operation with foundry men and Foseco experts. Typically, these filter prints are placed on the parting line. Positioned horizontally in the runner system and close to the downsprue, STELEX ZR filters will prime quickly, thereby ensuring a consistent flow through the whole filter area.

In order to avoid turbulence, abrupt changes in the direction of metal flow behind the filter should be avoided at all costs. This is especially important when casting steel alloys, because a turbulent flow will lead to reoxidation and risks the development of new non-metallic inclusions within the casting cavity.

		cleaner casting surfaces - reduced grinding conventional gating systems are possible
		less inclusions - reduced weld repair - no additional heat treatment
		reduced machining allowance - extended machine tool lifetime
		reduced cleaning time - shorter lead times
		lower inspection costs