CASE STUDY No. 9501
KEY WORDS= COOLING SYSTEMS, WATER TREATMENT, HEAT EXCHANGERS, BRAZING FURNACES
Modine Manufacturing Company
600 Water Street
Logansport, IN 46947
Contact: Joseph H. Gibson III, Mfg. Engr. Tel: 219-722-2211 Fax: 219-722-6331
Summary
A linear kinetic cell has replaced a chemical (carbamate) for treatment of water used to cool brazing furnaces. Initial cost, $14,763; payback period, 11 months.
Action
Modine manufactures oil cooling units for internal combustion engines. Metal parts are joined by brazing, a high-heat process. The vacuum brazing furnaces are cooled with water. The water must be treated continuously to reduce its electrical conductivity and inhibit scaling in various cooling components. Previously, a chemical (carbamate , Dearborn 945) had been used for this purpose. The consumption rate was approximately one 55-gallon barrel a month at a cost of $1,350.82 (493 lbs. /barrel x $2.74/lb.);`12-month cost,$16,209.84.
Carbamate treatment has been replaced by a kinetic cell installed in-line in the closed loop water cooling system. The cell is Ener-Tec LKC manufactured by Ener-Tec, Inc., 306 Railroad St., P.O. Box 85, Union City, MI 49094. 517-741-5015. It operates on 120 VAC; additional electric power consumption is about $42 a year. The cost of the cell was $14,033 and the installation cost was $730, chiefly to reroute drains (the cell works best if placed on the water inlet side of heat exchanger). The cell was installed at Logansport on 8/93 and has a life expectancy of 7 years. Maintenance includes periodic checking of power consumption and water flow.
This opportunity to reduce cooling system costs first came to the attention of an engineer at the Modine plant in Washington, Iowa. Upon presentation of the economic justification, management gave its OK and the new system was installed within a month. Subsequently, all Modine plants with brazing operations have made this conversion.
Payback
The original treatment method cost $16,209 a year. The new method cost $14,763 one time, for a payback period of about 11 months. Spreading the cost of the cell alone over its expected 7-year life, annual operating cost would be $2,004, or 12% of the cost to use carbamate.
Additional Waste Prevented
Substituting a linear kinetic cell may yield these additional benefits, according to Modine:
