STELEX filters for steel and high temperature alloy filtration smooth metal flow and mould fill when used in a conventional gating system. They also remove non-metallic inclusions such as furnace and ladle refractory materials and slag, moulding sand, products of de-oxidation, and re-oxidation. Filtration provides improved casting quality, productivity, and profitability. The casting producer benefits from reduced re-work costs associated with welding and cleaning, reduced casting returns, and often increased casting yield. In addition the casting exhibits improved machinability facilitating improved machine tool life.
STELEX ZR zirconia filters
STELEX ZR filters are based on zirconia which generates a highly stable refractory material offering a unique combination of thermal shock resistance, resistance to chemical attack, hot strength and creep resistance.
STELEX ZR ULTRA filters enable even higher filtration efficiency to be achieved through the use of finer pore filters. An integral ceramic frame around the filter enhances the strength which enables improved performance consistency.
Benefits:
Improved Production Costs
Shorter Lead Times
Improved casting quality
Consistent Performance
Ability to use finer porosity filters for even higher filtration efficiency
STELEX PrO carbon alumina filters
STELEX PrO filters have a low thermal mass and are ideally suited for application to carbon, low alloy and manganese steel casting production. These filters provide optimal priming characteristics and are therefore suited to applications where metal chill by the filter are a concern. Because STELEX PrO filters effectively prime at lower temperatures than traditional zirconia based filters, the application of filters to steel castings is expanding.
The particular benefits of STELEX PrO foundry filters are:
Consistent priming means that pouring temperatures for conventional gating systems are achievable
Reduction of temperature related defects
High filtration capacity including high flow rates
Flexible filter positioning - the filter can be placed horizontally and vertically and is ideally placed at the ingate
When used in the KALPUR direct pour system the filter will float to the feeder surface after pouring, reducing the risk of secondary shrinkage and maximizing feeding efficiency
No negative influences when remelting returns containing filter material
Lower costs for energy
Lower costs for refractory materials
HOLLOTEX Running and Gating System Components
Centrifugal filter units
HOLLOTEX CFU products are highly engineered filtration devices used exclusively in the production of large ferrous castings. The device comprises of a HOLLOTEX Refractory Centrifuge System and STELEX Ceramic Foam Filters.
The HOLLOTEX refractory centrifuge system separates inclusions from the molten metal before it reaches the filters. The integral STELEX ZR filters remove remaining contaminants from liquid metal and reduce turbulence as the mould cavity fills.
Filter holders
The HOLLOTEX C5-FH filter holder is a highly insulating 2 piece assembly designed to allow the placement of ceramic foam foundry filters into hollow ware gating systems.
HOLLOTEX Shroud
HOLLOTEX Shroud provides a reliable method of shrouding the metal stream as it exits the bottom pour ladle eliminating air entrainment in the sprue, and the subsequent formation of re-oxidation inclusions. The molten metal is therefore cleaner, allowing a higher level of filtration efficiency and turbulence reduction in the production of large steel castings.
The KALPUR direct pouring process is the combined use of a feeder sleeve and ceramic foam filter. It replaces one of the conventional feeders and the conventional gating system. Liquid metal is poured directly into the unit which connects directly with the casting cavity.
Casting clean: today’s solutions and opportunities
Learn more about improving casting quality in steel casting applications in our white paper Casting clean: today’s solutions and opportunities. This paper cuts through the noise and brings clarity to the clean steel debate: an overview of common casting defects is followed by a detailed review of the technologies currently on offer to reduce casting defects and improve cast quality at each stage of the steel casting process.
