Abstract: There are some problems in use of PDB in oilfield in China，the structure and working principle of the pneumatic disc brake are analyzed and the brake stroke model is built.The collaborative system simulation of pneumatic，control and mechanical system is achieved with AMESim.On the basis of the multiphase coupling model，the jumping trace of torque and velocity of the braked shaft are worked out in the course of braking.And effects on different parameters of brake system，such as brake pressure，friction coefficient and stiffness of restoring spring are also discussed.The simulation results show that the pneumatic disc brake has the merits of sufficiently braking abilities and rapid response，air pressure shock and vibration effect may happen to braking course，which can provide a valid theoretic basis for design and technique alteration of the pneumatic disc brake.The method of AMESim modeling provides a simple，effective approach to study pneumatic disc brake system.

Key words: pneumatic disc brake（PDB）, brake characteristic, collaborative system simulation, AMESim, oil drilling rig