Machine shops using water-based metalworking fluids are being urged to initiate a regular system cleaning regime, amid fears that too many operators are short-changing their cleaning processes in order to reduce machine downtime

The warning, from Millers Oils, is specifically aimed at machine shops using water-based coolants, which are susceptible to bacterial growth that can severely impact fluid stability and its operational performance.

Martyn Mann, Technical Director at Millers Oils, commented: “The issue is that operators all-too-often do not understand the necessity of system cleaning, whilst their production directors are happy for them to shorten cleaning time, in order to reduce overall machine downtime.

“Insufficient cleaning is merely storing up problems for a later date, because dirty fluid will inevitably have debris and other contaminants, including bacteria which feed upon the fluid, reducing its operational effectiveness and ultimately impacting machine performance, tool life and finished workpiece quality.”

Millers Oils recommends regular monitoring and testing of metalworking fluid for both bacteria and pH value to ensure that the fluid remains in top condition, allied to a regular cleaning regime. “Weekly checks, such as dipslides or refractometers, will ensure that bacteria is kept under control and pH levels are at their optimum. Low pH levels, for example, could be due to microbial contamination and ultimately lead to reduced corrosion protection,” says Martyn.

He continued: “A regular cleaning regime will eliminate many of the machining problems that operators are facing on a daily basis. Coolant systems need to be regularly cleaned in order to function properly and that means the sump, pipework, machine and guards, before re-filling with fresh metalworking fluid. Be careful to ensure that you are using a system cleaner compatible with the fluid and don’t ever put clean fluid in a dirty machine or sump.”