Case Studies

Capital Refractories are now able to offer an extensive series of gas diffuser products for the treatment of melts across a range hot metal industries.

Experience at an Investment Foundry

Capital has converted an investment foundry from chrome-alumina crucibles to Coral SMC fitted with a gas diffuser. Before conversion the crucible would last one day (18-20 heats) before erosion necessitated its replacement. The photographs here show the Coral SMC lining after a day. The lining surface is very clean and overall life much extended. The life expectancy of the furnace is now about 1 week between re-lines.

More Gas Diffuser Success

Capital Refractories has again demonstrated the huge benefits that can be achieved by employing a gas diffusers within an induction furnace. Capital recently worked in conjunction with Weaver Materiel, their distributor in the State of Pennsylvania. The foundry manufacture steel castings for the oil and refining industry, and were looking for a way in which they could de-gas the whole melt rather than having to adopt the SPAL method (i.e. spraying liquid argon onto the top of the melt), therefore reducing their costs and achieving a better surface finish on their castings.

Weaver Materiel installed Capital’s Coral SMC lining along with a standard 3 inch gas diffuser (model 7126). They were on site for the full 2 day trial, instructing all melters and supervisors on the procedures involved with the simple installation and running of the plug. In line with Capital’s policy, all distributors offer ongoing support to their customers if needed.

Benefits reported:

  • Huge financial and environmental savings in the gas used.
  • Improved surface finish on the castings due to the ability to de-gas through the whole melt.
  • Hardly any wear on the Capital lining.
  • Easier to pour metal into the moulds – cleaner metal means that pouring can be done faster through the pouring cups and filters.
  • Scrap rate reduced.

This Pennsylvanian foundry has since reported a substantial financial saving along with an improvement in the quality of their castings, and have already placed further orders for Capital’s combined lining and gas diffuser product.