A new technique for manufacturing high pressure cavity plate for heat exchange applications developed by the Australian stainless steel industry increases the options available to the food processing and manufacturing sectors.
'Laser welded cavity plate' has been developed by ASSDA member J Furphy & Sons, a Shepparton fabricator of stainless steel tanks and processing equipment, as an alternative to resistance or plug welded dimple plate used for the heating or cooling jackets on stainless steel tanks, vessels and silos.
A wide range of industries stands to benefit from the new cavity plate, from dairy, brewing, food, wine, pulp and paper, chemical, pharmaceutical, refrigeration to textiles and manufacturing.
It is designed to be used in jacketed tanks, pressure vessels, shells and heads, troughing, chutes and hoppers, immersion plates, bank assemblies, baffles, ice-making plates, water chillers and food cookers.
The method of manufacture allows design flexibility enabling it to be tailored to specific performance requirements. It can be designed to suit both the flow characteristics of the refrigerant or heating medium and the required performance objective for the equipment by programming the cavity pattern and dimensions into a CNC controlled laser welding system.
The process involves laser welding two sheets of stainless steel in their flat form and inflating to form the cavity through which the cooling or heating medium is transferred.
The laser welds are exceptionally strong and have been burst tested in excess of 13 000 kPa, with most common demand being for operating pressures between 300 and 3 000kPa.
The product is available single embossed for uses where a flat inner wall is required or double embossed for immersion where both sides of the plate are utilised to heat or chill.
It is in use in chocolate crucibles in the confectionery industry as well as in Peerless Holdings’ edible oils processing tanks. Orbis Engineering has used the cavity plate in a cooling tunnel conveyor bed and Barry Brown & Sons has utlised it in on-farm milk silos. It has also been used in various major winery projects, including Peace Wines and Jindalee Estate, for fermentation and storage vessels.
Another ASSDA member, A&G Engineering of Griffith, has specialised in cavity plate for use as a cooling plate in wine vessels for a number of
years. This product also incorporates technology unique to Australia.
This article featured in Australian Stainless magazine - Issue 22, September 2002.