Abstract: Tension device and deviation rectifying devices are basic configuration of a web former, and they are mainly composed of tensioner, steering roller, detecting and sensor device, controller, etc. Tension device keeps the conveyer belt under pre-set tension and it is used for torque transmission; the deviation rectifying device ensures the conveyer belt to automatically operate at the correct position. The paper analyzed and evaluated the operating principles, functions and adjustments of the tension device and deviation rectifying device in details.

Key words: conveyer belt; tension control system; tension roller; displacement detection; steering roller;central position