Iron Foundry Cuts Melting Costs with Furnace Refractory.

Dependable and reliable service, on-time delivery and innovation are key business elements for today's foundries. Elyria Foundry, Elyria, Ohio, demanded dependability and reliability when it agreed to test a different furnace refractory that had the potential to save the foundry in furnace maintenance costs.

Elyria Foundry produces castings from 50-80,000 lb and has four fully integrated foundries on its 30-acre site. The firm, which serves the refrigeration and gas compressor, pump and valves, process machinery, internal combustion engines, power and transmission equipment and machine tool markets, has six induction furnaces. These include four 50-ton channel melting furnaces and two 20-ton holding furnaces with a total monthly melt capacity of 3300 tap tons of all grades of gray and ductile iron. The optimum melt rate is 7000 lb/hr for the entire campaign.

Until November 1998, Elyria was using a magnesia-based refractory in its six furnaces. This system experienced 6-month campaigns and poor performance on its four primary melting furnaces. Elyria was conducting six lining changes/year and eight inductor changes/year. Due to channel closings, inductor clogging and poor upper case lining life, the foundry experienced unplanned down time and decreased ability to meet production demands.

Norton Foundry Systems, Worcester, Massachusetts, offered a solution with a new refractory system. In agreeing to test the new system, Elyria demanded a 1-year continuous campaign at the optimum melt setting. With the average total cost of a lining change at $100,000, Elyria wanted to eliminate as many changes as possible with downtime limited to 3 weeks/furnace.

Since this new refractory design reduces clogging, resists wear and is not attacked by chemically-based oxides, the result was 13 months of uninterrupted service with limited wear to the lining and immediate dollar savings. The supplier engineered a refractory system utilizing three different dry vibratable materials in the uppercase of Elyria's furnace: one to address abrasion, one to address slag attack and one to address mechanical abuse. Since the end of the initial campaign in December 1999, the foundry now has five of six furnaces running with the refractory lining.

Other benefits include:

* 50% reduction in downtime and lining change costs: only four lining and inductor changes/year vs. previous eight resulting in an additional 3 months of production time;

* average of 13 months lining life vs. 6 months;

* reliable melt at 1500 kW through the life of the campaign;

* reduced inductor clogging. (Elyria also installed new metal bottoms to the furnaces that include perimeter water cooling around the inductor flange that greatly reduces the risk of hot spots).

According to L. Kim Bevington, vice president-operations, "the increased 'furnace up-time' also has increased our pouring capacity which better services their casting requirements."