2015.09.06 Maintenance

Choose the correct metalworking fluid for your water

When choosing metalworking fluid, you should first find out what kind of water you have. If the MWF is not compatible with the water used, problems like foam can arise.

The quality of the water is very important in view of the fact that water constitutes over 90% of the metalworking fluid. Urban water is often first-rate, with a uniform quality, nevertheless, problems can arise.


Over time, the salts that are present in the water, for example, chlorides and lime, can cause rust and deposits in the system. Even though the water evaporates, the salts remain and are thus concentrated in the system.

Rule of thumb: Never have > 100 ppm chlorides in the metalworking fluid!

A de-ionizing plant can be a good investment if you have major problems with salts. It is used for top-up.


The water's properties affect the choice of metalworking fluid. If the metalworking fluid is not compatible with the water that is used, it can result in, for example, formation of foam in the metalworking fluid.

One of these properties is the water's hardness, which varies depending on where in the world the production is located. For example, the water is soft in Sweden while it is hard in Germany.


Read more about process fluids in our e-book.

E-book: UV light

Hans Ahlgren
Hans Ahlgren

Hans introducerade processvätskerening inom Wallenius Water 2011 efter ett flertal lyckade fältinstallationer. Processvätskerening är idag ett av Wallenius Waters fokusområden. I dag arbetar Hans med strategisk partnerutveckling inom affärsområdet.

+46 8 120 138 37
Hans introduced process fluid purification within Wallenius Water in 2011 after several successful field installations. Today purification of process fluid is one of Wallenius Water's focus areas.

+46 8 120 138 37
Hans führte die Reinigung von Prozessflüssigkeit innerhalb Wallenius Water im Jahr 2011, nach mehreren erfolgreichen Feldinstallationen, ein. Heute ist die Reinigung von Prozessflüssigkeit eine der Schwerunkte von Wallenius Water.

+46 8 120 138 37


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