Page 16 - Industrial Technology EXTRA 19th July 2021

to or below the base oil’s pour point, they can no with cages can perform at temperatures close to
longer do this effectively and accelerated wear can -200 degrees Centigrade. Full complement silicon
occur. A larger amount of thickener in a grease can nitride bearings can operate at temperatures of up
also cause it to stiffen too much at low temperature. to 800 degrees Centigrade. In extreme conditions,
lubrication can be a problem. One option is to run
More than lubrication the bearing “dry” without any lubrication at all. Full
It is also important to select the most suitable ceramic bearings will operate without lubrication
bearing material. SMB Bearings supplies 316 but for stainless steel bearings, rotational speeds
stainless steel bearings which can be used down to must be extremely low.
almost -200 degrees Centigrade, and up to 250 When operating in harsh environments,
degrees, depending on the cage material. However, incorrect lubrication can not only slow down the
they are semi-precision and only suitable for rotation speed of a bearing, but potentially restrict
relatively light loads due to the difficulty in its movement completely. This obviously has
hardening 316 grade steel. 440 grade bearings are disastrous consequences for machinery operating in
ideal for high load and high precision applications extreme environments. That’s why it’s vital that
but may suffer from corrosion. manufacturers approach bearing suppliers with the
Full ceramic bearings are recommended in skills and industry knowledge to advise on the best
corrosive environments or extreme temperatures lubrication choice, otherwise they could be left out
where higher loads and speeds must be tolerated — in the cold.
they have excellent corrosion resistance and those www.smbbearings.com

July 2021 • INDUSTRIAL TECHNOLOGY EXTRA • p16