Slide ways and linear guides require proper lubrication to achieve high accuracy for machine tools. Lubricants called slideway oils are commonly applied using automatic lubricators to these parts which naturally drip or throw off into the sump tank during operation. Slideway oils perform the following functions:
- Reduce the stick-slip effect on the slideways movement to optimize machined parts’ positional accuracy, especially for precision parts,
- Provide slideways rust and corrosion protection, especially where water-miscible cutting oils are used, and
- Prolong the slide’s working life through lubrication. Slides, typically made using cast-iron, experience high sliding friction and friction from the force of machining.
In choosing the correct slideway oil, start with not using hydraulic oils or gear oils even if they have the same viscosity. Doing so can damage the machine tool and affect machined parts quality as these lubricants do not contain additives such as tackifiers and friction modifiers found in slideway oils.
Consider the following parameters when selecting which slideway oil to use for your machines:
Correct Viscosity
OEMs usually recommend ISO VG 220 oils for vertical slides and ISO VG 68 oils for horizontal slides. There are some OEMs that recommend ISO VG 100 and ISO VG 32, respectively.
Presence of Extreme Pressure (EP) Additives
EP additives form a protective anti-welding film between two metal surfaces required for high boundary lubricating conditions such as in slideways.
