Wallwork Cast Alloys were called in to look at problems of cracking that reduced the working life and efficiency of stainless steel base grids and pan casings used in the heat treatment furnaces. Independent Forgings original supplier was unwilling to alter the design or material and so Wallwork were asked for an alternative.
A heat treatment specialist, producing furnace furniture for their own factories Wallwork’s working experience is used in the design process. “We understand the need for strong and resilient low thermal mass designs that optimise component packing density to achieve even heating and effective quenching,” commented Wallwork director Peter Carpenter.
“We examined the failed grids and casings and concluded that we could extend their life by a design modification to the pattern and substituting a 55/18 nickel/chrome alloy for stainless steel to achieve a higher temperature tolerance,” explained Peter. “Castings that remain structurally sound and have a good working life are vital to profitability.”
Independent Forgings and Alloys speciality is open die forgings in carbon and stainless steel, alloys of nickel and titanium. These are ultimately used by clients in demanding industries such as nuclear, defence, aerospace, oil, gas and power.
Pawel Grzesiakowski, heat treatment manager at Independent Forgings and Alloys commented, “We use various heat treatment processes such as hardening, tempering, solution treatment, ageing and stress relieving in temperatures ranging from 420 to 1230 degrees C. All processes follow exacting quality control procedures to ensure that we meet each customer’s metallurgical needs. The engineer from Wallwork had an instant understanding of how we use the grids and pan casings. After inspection of the failed units he was able to tell us how a better design would be stronger in the vulnerable areas, reduce weight and improve the thermal performance of the casting.
“Modern design and casting methods produce foundry furniture that is lighter and stronger. Lowering the weight of the casting enables the process to attain optimal temperature more quickly – meaning more cycles per shift to improve productivity. In turn, this reduces process cost per component as well as lowering energy use and carbon release. Extended working life for jigs and castings also contributes toward lean goals because less capital is tied-up in these tools,” summarised Peter Carpenter.
Wallwork Cast Alloys carry in stock standard patterns for use with Barfield, Seco Warwick, Ipsen, Wild, Wellman and other heat treatment furnaces. Furnace furniture is usually produced in a 37/18 nickel/chrome ferrous alloy to retain strength to 1050 degrees C. The company also produce castings of up to 80/20 nickel/chrome that can work up to 1250 degrees C.
A custom 3D pattern making service is available to Wallwork clients. Typical turnaround for furnace tools is six to eight weeks where pattern making or customisation is needed. Where the pattern is already held and no modification is needed turnaround time is less and the company also has an express service to meet special circumstances.
Simeon Collins, Sales Director
Tel. +44 (0)161 797 9111 Fax. +44 (0)161 763 1861
Wallwork Heat Treatment Ltd, Lord Street, Bury, Greater Manchester, BL9 0RE
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