Six Year Evaluation of RIVS System

Data has been collected from eleven foundries using the RIVS to line furnaces of 9 tons or greater capacities, melting grey, ductile iron or copper. Ten lined furnaces with silica, one foundry melted copper and lined with alumina-based refractory. Consistent and sustained improvements in operation and health and safety conditions were shown by all foundries using the advanced technology during the past 6 years. A summary of the principal results and benefits is detailed below.

1. Air Samples for Respirable Silica - produced results between <0.01 and 0.02 mg/m3 when lining with the RIVS; five to ten times below OSHA's (Occupational Safety and Health Association) permissible exposure levels.
    
2. Densities of linings - every foundry added more material than when manually lining a furnace, producing a denser lining. Only 5 of 11 foundries measured the densities of manually installed and RIVS installed linings. The densities of the conventionally produced linings ranged between 124 and 130 pounds/cu. ft. while those produced by the RIVIS measured the maximum for silica between 137 and 139 pounds/cu.ft.
    
3. Lining Life - adding more material for a denser lining resulted in longer lining life in every foundry using the system. Typically, furnaces lined manually (with silica) lasted between 3.5 and 5.5 weeks. The RIVS lined furnaces lasted on average 2 weeks longer. In one foundry lining life increased 100 percent (from 3.5 to 7 weeks) and at another 143 percent improvement above manually lined furnaces. The 30-ton furnace lined with alumina based refractory lasted 50 percent longer than when lined conventionally.
    
4. Workforce Reduction - Two workers operate the RIVS system despite the size of the furnace. Foundries surveyed manually lined furnaces using between 5 and 8 workers, depending on the size of the furnaces. The RIVS reduced that number to two, for a reduction ranging between 57 and 83%. Hours of labour to line a furnace decreased on average by 74% and overall elapsed time decreased by approximately 37%.
    
5. Tonnage Throughput - All foundries reported a higher tonnage throughput per campaign simply because linings lasted longer. Increases ranged between 28 and 67 percent longer than when furnaces were conventionally lined.
    
6. Fewer Annual Linings - Foundries reported an average 42% fewer linings annually using the system. Considering the cost of tear-out, relining and sintering each furnace, return on investment was significant.
    

Further Developments of the Refractory Installation and Vibration System

A generation 2 system to line furnaces between 3 and 8 tons capacity is in the final stages of development. The principles of superior deaeration and consistent even distribution of material applied to larger furnaces has been maintained.