Best Practice for Machine Shop Christmas Shutdown

Millers Oils Fluid Management Technician, Zane Alqadi, gives best practice tips for looking after your cutting fluid over the holidays. Proper planning for a Christmas shutdown can save both time and money on your return. This is especially true for machine-shops using water soluble cutting fluid.

What can go wrong?

Due to their water-based chemistry and the open environment in which they operate, metalworking fluids need regular checks to ensure the product is in good condition and free from contamination. If the concentration deviates from the recommended level, or the sump becomes contaminated by bacteria or fungus, the product can rapidly degrade. This is in particular when not in use for a prolonged period like the Christmas break.

What preventative actions can be taken?

Ideally, small sumps should be drained and cleaned out prior to shutdown. This is to eliminate the risk of contamination and degradation while the machine isn’t in use. That’s not always practical, and certainly for larger sump sizes we’d recommend taking some preventative measures instead:

• On the last full day of operation before the machines are started up, remove any tramp oil from the surface of the fluid. Once the machine is up and running, check the concentration and pH of the sump.
• If the concentration and pH are within the correct range, top up to the highest recommended concentration and maximum level in the sump. This will give the fluid the best chance of fighting off any microbial contamination while not in use. If the pH is a little low, I’d advise pre-dosing with a tank side treatment while the machine is still in operation. This is in order for it to circulate throughout the machine.
• At the end of the shift, ensure sumps are covered where possible to avoid both airborne contamination and evaporation losses.

What’s the best way to quickly get back up and running?

When you return in January after the shutdown, take off the sump lids and remove any tramp oil that has settled on the surface before starting up the machines. Test all the fluid concentrations and pHs again. If the sumps haven’t been covered then the concentration may be too high due to evaporation loss. If that’s the case, then top up with a weak mix to return the concentration to its recommended level.

Where the pH is low but the concentration is correct, I’d recommended checking for bacteria and fungus using dip slide tests before using a tank side treatment if required.

Once the fluids are back to their optimum condition, you’re ready to start the new year with improved work-piece finish, extended tool life and reduced unplanned down-time.

For further information regarding metalworking products or Fluid Management services, contact fluid.management@millersoils.co.uk or find out more here: Fluid Management Division – Millers Oils