WZB-2 boundary lubrication bushing is based on a composite material with 3 firmly bonded layers : steel as backing , sintered bronze spherical powder as interlayer and modified POM. as lining layer. It fits well for low speed, heavy duty and normal teperature and saves cost and prolongs working life when replacing normal all copper sleeves. It is widely applied in auto chassis forging machine, metallurgical and mining machine, civil engineering, power atation, striprolling industries etc.