Leakage caused by imperfect sealing of the pipeline will affect the quality of concrete pouring on the one hand, and reduce the slump of the concrete and the loss of pumping pressure on the other hand, which will lead to the blockage of the pipeline. The pipeline joint is not tightly sealed, the pipe clamp is loose or the sealing ring is damaged, causing slurry leakage. At this time, the pipe clamp should be tightened or the sealing ring should be replaced. If the piston is worn, it should be replaced in time, otherwise the pipeline will be blocked due to slurry leakage and pressure loss, and the wear of the piston and the delivery cylinder will be aggravated.
Before pumping concrete, the pipeline should be lubricated with clean water, and the mortar should be transported first, and then the concrete should be transported to prevent the pipeline from being blocked. After wetting the pipe with water in front of the pump, loosen the pipe joint from the low point of the pipe to drain all the remaining water, or put a sponge ball after pumping and before pumping the mortar to separate the mortar from the water. When cleaning the pipeline after pumping the concrete, put in a sponge ball to separate the water from the concrete, otherwise it is easy to cause the pipeline to block. After pumping the concrete, the hopper and piping system must be cleaned carefully. If the residual concrete in the cylinder is not cleaned up, the concrete will easily solidify on the cylinder wall. When the piston is running again, the piston sealing surface will directly bear the impact of the solidified concrete on the cylinder wall, causing partial peeling of the pushing piston. This damage is different from the normal wear and tear of piston seals. The sealing surface cannot compensate itself under pressure, causing slurry leakage or suction, causing pumping weakness, pipeline blockage, etc.
In summer, when the temperature is high and the pipeline is exposed to strong sunlight, the concrete is easily dehydrated, causing the pipeline to block. Therefore, the pipes should be covered with wet grass curtains, and water should be sprayed frequently. In winter, use insulation straw curtains to prevent heat loss and affect the workability of concrete.
(1) Repeat the operation of the reverse pump and the forward pump, gradually suck out the concrete and return it to the hopper, and then send it after mixing evenly.
(2) Use a hammer to find out the blockage. After the concrete becomes loose, repeat the reverse pump and forward pump operation to remove the blockage.