If the filter cloth only slides towards one side of the filter constantly, check as follows:            

1. Check that the air supply is on. Refer to "air requirements" above. Check the air filter and clean it if necessary.            

2. Check the limit switch lever. The contact rod should touch the filter cloth slightly. When the filter cloth is in the middle, its normal position is at 0 degree to the vertical line.           

 If the contact angle is greater than or less than 16 degrees and the filter cloth continues to slide to one side, the following measures should be taken:           

 1) Stop the filter           

 2) Push or pull the contact rod of limit switch by hand according to the offset direction of filter cloth. The straightening roll should start or continue to move. If not, it means that the position of the contact rod needs to be adjusted.           

 3) If the air cylinder has been fully inflated, and the deviation correction roll can not be corrected, it means that the angle of the centering wheel can be further adjusted at the bearing on the drive side. At the same time, in the slot hole of the driving side roller, the bearing of the driving side rotary roller is moved according to the travel direction of the filter cloth, so that the filter cloth is in the middle of the filter. Fix the driving roller and wait for at least 15 minutes to check whether the filter cloth returns to the middle. Remember, when the filter cloth is in the centering position, the cylinder on each side does not act, and the contact rod of the limit switch forms a 0 degree angle with the vertical line of the filter cloth, which should just touch the filter cloth.           

 4) If the contact rod of the limit switch moves, the cylinder is not fully extended and the rotary roller does not move, check whether the air pipe is loose or whether the air supply is sufficient. If these are not the problems, and the airbag does not respond to the movement of the touch bar, then the problem may lie in the airbag or the limit control device.           

 Other reasons for dislocation and fold of filter cloth in vacuum belt filter            

The wrinkling of filter cloth is often caused by incorrect alignment of filter cloth, but some misplacement can not be corrected only by rotating roller. The details are as follows:          

  1. Insufficient tension may cause wrinkling. Although the filter is equipped with a weighted rotating wheel to tension the filter cloth, the wheel also needs to be weighted additionally. The sliding block of the rotary roller is provided with a notch for weighting.          

  2. Improper joint of filter cloth at the joint can also cause wrinkling.           

 3. Sometimes, the deposition of solid matter on the filter cloth roller or sliding adjusting block will cause dislocation and wrinkling of the filter cloth. When this happens, stop the filter and thoroughly clean the rollers and sliding blocks. Start the driver and readjust the filter cloth for alignment and tension. Then carefully observe the accumulation of solids during the normal operation of the filter. If necessary, the amount of flushing water can be increased to remove the residual solids.          

  4. Dislocation and wrinkling may also be caused by the misalignment of the take-up wheel or other rolls. This kind of dislocation is manifested as the diagonal deflection of the zipper of the filter cloth. Due to the uneven distance of the outer edge of each side of the filter cloth, one side of the filter cloth is ahead of the other side in the walking direction around the filter, so the travel distance of the leading side is shorter. This phenomenon can be corrected by adding a balance weight on the sliding adjusting block of the tension wheel to reduce the tension on the trailing side of the filter cloth and shorten the travel distance of the trailing side of the filter cloth. This problem may also be caused by the misplacement of the filter cloth support roller. Check whether all the filter cloth support rollers are aligned with the frame.          

  5. During any such adjustment, the filter cloth shall be kept centered and wrinkle free for at least half an hour. Because many filter cloth is easy to shrink after being wet, it will cause the filter cloth to be either narrow or much larger than the final use size. For this reason, it is recommended that there should be a period of cloth stabilization before any major adjustments are made for alignment.