Areas of Application for MQL

In the early days of minimum quantity lubrication (MQL), it was mostly limited to a few processes and materials. Gray cast iron was particularly preferred because of the relatively high proportion of graphite, which has comparable properties to a lubricant. Then as now, aluminum or iron were also suitable for the use of MQL-systems. Today, however, even materials that are difficult to machine (i.e. process martensitic chrome steels) can be processed using MQL.

The table below provides information about the possible choice of the cooling-lubrication method depending on the machining process and the material used. This clearly shows that many areas of application are suitable for minimum quantity lubrication.

Material / Method Aluminum Steel Cast Iron
Cast Alloy Wrought Alloy High-Alloy Steels Free Cutting Steel  
Drilling MQL MQL MQL Dry Dry
Rubbing MQL MQL MQL MQL MQL
Threading MQL MQL MQL MQL MQL
Thread Forming MQL MQL MQL MQL MQL
Deep Drilling MQL MQL   MQL MQL
Milling Dry MQL Dry Dry Dry
Lathing MQL / Dry MQL / Dry Dry Dry Dry
Hobbing     Dry Dry Dry
Sawing MQL MQL MQL MQL MQL
Clearing     MQL MQL / Dry  

The areas of application for our minimal quantity lubrication technology systems largely coincide with those of conventional lubrication-cooling solutions, e.g.

  • sawing
  • cutting
  • milling
  • drilling
  • lathing
  • profiling
  • etc.

For technical reasons, MQL-technology is most effective when the tools have a defined, symmetrical cutting edge, e.g. when drilling, sawing or milling. In principle, geometrically undefined cutting surfaces, such as those found in grinding and honing machines, are less suitable for minimal lubrication technology. These latter methods are nowadays mostly implemented using conventional flood lubrication, which, in addition to the cooling and friction-reducing effect, ensures that the chips are removed from the work area. Processes in which lubrication is a priority are generally more suitable for MQL-technology.