The fact is, coolant does not last forever & if left in the machine too long, it loses effectiveness, it can delaminate & it definitely becomes a health risk. Mineral coolants break down faster than synthetic types, but all should be changed periodically except where there is in-house coolant refurbishing apparatus, where one reservoir feeds multiple machines. Even there, regular checks should be maintained.
We have some suggestions that may help to effectively manage your coolants…. Coolants will deteriorate faster in the summer months. A good idea to empty all the machine sumps on the last day of the working year, refill with clean water, add biocide, recirculate the clean water for a couple of hours, then empty out entirely & allow the machine to completely dry. Bugs need moist conditions & warmth to survive. Drying out a sterilised machine sump will prevent any possibility of returning to work after your holidays, to a sump that looks like (& smells worse than) a load of cauliflower in sauce.
First day back, mix up the correct coolant ratio, but add some more of the biocide – it makes a difference. Coolant that is kept moving will last way longer than stagnant stuff. An interesting fact: adding oil to water will make the mixture not only last longer, but it’s less likely to delaminate or separate. And it does its job more effectively.
A few simple rules will help decrease your coolant spend.
Get the ratios correct:
- Usually 5-7% for general machining, 15% for sawing.
- Add a further 10-15% for difficult to machine metals.
- Add oil to water, NOT water to oil.
- Mix thoroughly.
Oil never quite completely mixes with water, but following this simple rule allows the particles of oil to be carried in suspension evenly.
Adding a top-up of a different brand or supplier?
Mineral oils are usually OK to mix. But best not to mix different brands of synthetic coolants because the chemical packages of different coolants could produce a volatile reaction…. Please empty out and refill with a completely new mixture. It’s a good idea to check your coolant pH levels occasionally, as a mixture that is acidic can potentially corrode the coolant tank & parts of the machine including electrical gear & proximity sensors. And disposing of spent coolant? Please do contact us
