Pulley block traction tension loop

The utility model relates to a metal surface treatment equipment, in particular to a pulley group pull type tension loop. The utility model is a device for storing and relieving the band material during the metal band material surface treatment. The utility model is characterized in that the device is composed of a fixing roller group, a movable roller group, a pulley group dragging device, a rack and a coiling device. A fixing roller group is fixed on the framework of the upper rack and the lower rack, a lead rail is arranged on the rack, the lead rail is connected with the movable roller group pulleys, the coiling device is fixed under the rack, the coiling device is connected with the fixing roller group and the movable roller group through the pulley group dragging device. Such a pulley group pull type tension loop can reduce the force energy parameter of the dragging device and fully utilize the motor power and omit the balance weight.