PTFE and lipophilic  friber can protect the shaft while the machine is in running-in operation.Bronze has good thermal conductivity, which diverts heat while the machine is in operating.It can be applied in the machine with working for a long time but with incapable examinations and repairations, because the bronze has self-lubricated prorerty.It is used in the weak acid and alkali conditions  because of its good anti-corrosion of bronze backing.It is widely used in steel metallurgy industry, such as bushes for roller grooves of successive casting machines, cement grouting pumps and scrow conveyers of machines.It can be composed in steel housing, or fabricated into fanged bushes which results in function for montion both on fange and I.D.