Pulse Firing Applied to Heat Treating

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TABLE 6: ECONOMIC RESULTS Annual production Gas consump­tion Annual gas consumption Annual gas cost .15$/M3 Annual savings CONCLUSION old furnace 2 treaments 84 and 3 treaments 85 per week 3980 m3/84 9401 m3/85 413920 m3~yr 84 1466556 m /yr 85 282071$ new furnace 2 treaments 84 and 3 treaments 85 per week 963m3/84 2976 m3/85 100152 m3/yr 84 464256 m3/yr 85 84661$ 197,410$ We have noted ' that the main advantage of pulse firing is to provide temperature uniformity in the furnace. A variation of 4.4 0c was measured between the various zones in the furnace. Before this gradient was around 22 0c. This leads to improved metallurgical quality of the treated parts and ultimately to a larger span of possible treatments existing on the market. Furthermore a lower thermal inertia of the furnace allows to reduce time lags between two treatments thus allowing an increased productivity. Energy savings are 72% on the average;of which 71% can be attributed to the following factors: -13% from the use of ceramic fibers -35% from the use of flue dampers -23% from the pulse firing system. It must be pointed out that it is critical to maintain a proper calibration of the cooling mode in order to achieve maximum energy saving. REFERENCE Martin,T. Pulse Firing: How and What. Hauck Manufacturing Company, Lebanon,PA.