1. Operators are not focused

The operators of the delivery pumps should concentrate during the pumping construction and always pay attention to the reading of the pumping pressure gauge. Once the pressure gauge reading suddenly increases, they should immediately reverse the pump for 2 to 3 strokes and then pump forward to eliminate the pipe blockage. If the pipe blockage has not been eliminated after several cycles of reverse pumping (forward pumping), the pipe should be removed and cleaned in time, otherwise the pipe blockage will become more serious.

2. Improper selection of pumping speed

When pumping, the selection of speed is critical. Operators cannot blindly map fast, sometimes haste makes waste. When pumping for the first time, due to the large resistance of the pipeline, the pumping should be done at a low speed. After the pumping is normal, the pumping speed can be appropriately increased. When there are signs of pipe blockage or the slump of a truck of concrete is small, it should be pumped at a low speed to eliminate the pipe blockage in the bud.

3. Improper control of the amount of residual material

When pumping, the operator must always observe the residual material in the hopper. The residual material must not be lower than the mixing shaft. If the residual material is too little, it is very easy to inhale air and cause pipe blockage. The material in the hopper should not be piled too much, and it should be lower than the guardrail to facilitate timely cleaning Coarse aggregate and oversized aggregate. When the slump of a truckload of concrete is small, the remaining material can be lower than the mixing shaft and controlled above the "S" pipe or suction port to reduce the mixing resistance, swing resistance and suction resistance. This method is only applicable to the "S" valve series concrete pump.

4. Improper measures when the slump of concrete is too small

When it is found that the slump of a bucket of concrete is very small and cannot be pumped, the concrete should be released from the bottom of the hopper in time. If you want to save trouble, forced pumping is very likely to cause pipe blockage. Do not add water to the hopper for mixing.

5. The downtime is too long

During the downtime, the pump should be turned on every 5~10 minutes (the specific time depends on the temperature of the day, the slump of concrete, and the initial setting time of concrete) to prevent pipe blockage. For concrete that has been initially set due to long downtime, it is not suitable to continue pumping.