Views: 728 Author: Site Editor Publish Time: 2019-08-12 Origin: Site
Jiangsu Yuanding Science and Technology Co., Ltd. using calibrated strength screws or springs or pneumatic/hydraulic cylinders can prevent permanent shaft bending. strength screws to fasten the crossbars to the stand. These screws act as “shear pins”. However , the simplest solution to avoid shaft bending is to use an elastic top shaft (bearing block) holddown mechanism such as pre-loaded springs, or pneumatic or hydraulic cylinders. A drawing of a typical stand is shown below. CZ PURLIN ROLL FORMING MACHINE
Most roll forming machine made in JIANGSU YUANDING have the bottom shafts in a fixed position above the machine frame. The top shafts can be adjusted up and down with screws. To allow easy and accurate adjustability of the top shaft, the lifting/pushing screws above the bearing blocks, and their attachments to the bearing blocks and to the cross bars, must be free of play, with gaps not exceeding 0. 0005 in. (0. 015 mm).
The bearing blocks should move freely up and down, but the gap should be sufficiently small , especially at the drive side, that when the operator-side stands are removed, the end of the shafts cannot be moved up or down by hand.
The approximate position of the upper shafts is shown on a vertical scale fastened to the side of the stand. A more correct up and down adjustment can be observed on the micrometer scale attached to the adjusting screws. The micrometer scales at both the drive and the operator part shall show the same number when the shafts are exactly parallel.
It is essential that all shafts should be set exactly at 908 to the direction from the strip travel during installation of the drive-side stands. The smallest angular deviation can create serious roll forming problems.