Adding Machine Coolant Filtration Systems in a Carbide Tool Grinding Operation

A shop with six grinders for saws and tools bought six filter units for $9,000.  They bought an additional $600 in cleanable, reusable filters.  They had been spending $10,800 a year in machine coolant use and disposal.  Their machine coolant use and disposal dropped to $500. This is a saving of $10,000, which paid for the original investment.  The labor of filter maintenance was less than the labor of sump cleaning and recharging.  This shop does ultra-precise grinding.  The six machines had a depreciated value of about $550,000 dollars.  (This is considerably less than replacement cost, and uses IRS depreciation schedules.)  This is a savings of $55,000 a year in machine life.   The shop estimated another $10,000 a year in savings on grinding wheels because of longer wheel life and less need to dress the wheel since they did not gum up as rapidly.  The shop also estimates that they can work about 5% faster with no burning. 

For Information on a Machine Coolant Filter Unit that can save your shop money and contribute to cleaner and safer work environment refer to our Filtration Index. 

Machine Coolant Management - Annual Cost Calculations

Filter machine coolant and recycle instead of waste disposal. 

(Note: These results are several years old, and the costs of filtering are dramatically lower now so the savings are much greater now.) 

Cost of filter units

Cost Reduction

If you change your machine coolant every three weeks, and have the used machine coolant hauled away as hazardous waste, then you will spend $3,561.50 per year on every grinder or machine with a thirty-gallon sump.  In a shop with five machines this is $17,800 per year.  If you change the machine coolant every six weeks, and have it hauled away as ordinary waste, then you will spend  $4,300 per year for five machines.  This is a saving of $13,500 per year. 

Assumptions

1.  One machine with a thirty-gallon sump

2.  Machine coolant cost at $25 per gallon

3.  Machine coolant is mixed about 20:1 so it costs about $37.50 to charge a sump after each change

4.  Labor is at $20 an hour and it takes a half hour to drain, clean and recharge a sump

5.  Disposal costs

     A. Hazardous waste is $300 per each 55-gallon barrel

     B. Grinding machine coolant is $90 per each 55-gallon barrel

 Unmanaged machine coolant is not filtered, and is hauled away as hazardous waste.    Managed machine coolant is filtered at least one hour a day, and is classified as used grinding machine coolant for disposal.