Dry Lubrication is the simplest most convenient method of lubrication. However any bearing surfaces based on dry lubrication will progressively wear during relative movement

Dry Lubricants are generally based on Molybdenum Disulphide (MoS₂) or Graphite and sometimes combination of the two. Generally lubricants based on MoS₂ are used in the lubrication of machines and graphite based lubricants are used in specialised industries including hot metal working. Other speciality dry lubricants are available including Tungsten Disulphide. (Ref ws2 Link below.)

MoS₂ is a black crystalline solid which shears easily and has a low coefficient of friction . It is resistant to solvents chemicals and can be used at temperatures up to 250 ⁰ C.

Graphite has a thin flat crystalline structure which adheres strongly to metal surfaces and is a good conductor of heat and electricity. Graphite is relatively inert unaffected by acids, alkalis and solvents. As a lubricant it enables metal surfaces to resist seizure even at very high loads. However it results in more surface wear than MoS₂. It is therefore used less for lubrication of metal surfaces than MoS₂.

These are usually plain plastic bushes which have to be able to run with marginal or no lubrication. The main requirement of dry bearings is that the bearing surfaces have a low coefficient of friction. These bearings are used in undemanding applications such as low speed moving parts in domestic appliances, instrument and electro-mechanical devices.

Thermoplastic bearing materials are often filled with glass, carbon, bronze, lead. These bearings usually consist of a thin layer of bearing material bonded onto a metal backing. Bearings such as SKF GLYCODUR F and Glacier DU consist of a steel backing and a sintered bronze layer. The porous bronze is filled with ptfe and other friction reducing additives.