The main reason for the nonuniformity of the pipe wall is that the feed is not uniform and the amount of dry and hard concrete is large in the process of pipe making, and the pipe wall thickness is beyond the mold mouth. Uniform rolling pressure is not in a plane, making the die beating caused. Prevention is to strengthen the technical workers job training.
Wall surface Ma surface,not smooth
Resulting in the surface of the pipe surface Ma, not smooth There are three main reasons, one is because the mold wall of residual concrete clean. Prevention methods are: after the demolition of prefabricated pipe section, the steel mold on the inner wall of the concrete dry wire brush, clean the ball clean, and even brushing a layer of release agent.
Forming the inner surface of the pipe section of the contraction cracks
There are two main causes of shrinkage cracks in the inner wall of the tube after forming. One is the production of improper operation of the wall to achieve dense state, without a slow down and direct downtime. In strict accordance with the operating rules of construction, and pay attention to gradually reduce the speed.