Abstract:The concentricity of suspension hole is one of the key dimension for launcher,which affects the suspending accuracy,and this result in the tolerance is being made necessarily tight.According to the machining process,a fi xture which is comprised of the fl atted location pin,the location key and the base plate is presented.The fixture eliminates the six freedoms when work is located.The process calculation of the jig is also carried out.Accuracy is ensured by machining suitable location features,and the clamp can be operated quickly but with safety.The qualified concentricity of suspension hole is processed to meet the demand of mass patch production.