The circular winding machine completes the straight line into the moving (DBB) trolley, which is pulled forward by the pipe during the bending process. In this way, the "positive thrust" is eliminated and the problem of synchronizing the trolley with the bending speed is eliminated. The bending arm and the bending spindle are connected together, the bending die shaft of the bending pipe can be replaced, the clamping die moves up and down, so that the structure is not only reasonable, the strength of the mechanical part is increased, but also the structure is simple, so that the electrical circuit is simplified.
When bending, the trolley is pulled forward by the pipe as the load. In order to improve the bending, avoid excessive thinning of the wall thickness of the bending part of the pipe and reduce the springback, a boosting device is added. In bending, the die not only compresses the pipe, but is pushed forward by the thrust force to form a side thrust for bending. Removed the DC motor negative feedback system to increase the "positive thrust" and simplified the electrical circuit. Because positive thrust is beneficial to pipe bending, especially when bending large diameter pipes, positive thrust is necessary. Therefore, VB pipe bender added a boost device.