Metalworking fluid record form

Metalworking fluid (MWF) can deteriorate over time and cause ill health so you need to check and refresh it frequently. Use our record form to keep a note of your weekly and daily programme of inspection.

What’s covered?

To control the risk it’s necessary to ensure that the MWF system is properly maintained. Use one copy of the form per machine and per MWF product. Enter the “Location”, “Product” and “Machine”. You’ll also need to check and enter the capacity of the sump, the operating concentration and pH ranges. The “MWF refractometer correction factor” you’ll find on the product data sheet.

Visual monitoring

Your daily checks should focus on the odour and appearance of the fluid. Check the reservoir for changes in colour or clarity, foaming, contamination by oil/swarf, or separation of the liquid. Look for obvious signs of biofilm (slime) on the surfaces of the sump or filters and check for unusual odours, mould, rust or excessive amounts of swarf. Record your daily observations by ticking if you have found a problem and writing comments in the adjacent column.

Extra weekly tasks

Oils which are not part of the MWF product but derive from coatings on the material being machined or hydraulic oil from the machine itself are called tramp oils This contaminant can be identified by discoloured patches on the sump surface or in the MWF. Record the presence of tramp oil on a weekly basis.

Other weekly tasks are to take the temperature, test the pH and measure the concentration of the fluid. Compare these with the manufacturer’s acceptable range of values - 30˚C is the usual maximum temperature. It is also recommended that you use dipslides to check for bacteria levels, fungi and yeasts. Dipslide results above 10,000 CFU/ml indicate a level of bacteria requiring action.