The operator is not focused

输送泵操作人员在泵送施工中应精力集中，时刻注意泵送压力表的读数，一旦发现压力表读数突然增大，应立即反泵2-3个行程，再正泵，堵管即可排除。若已经进行了反泵(正泵几个操作循环，仍未排除堵管，应及时拆管清洗，否则将使堵管更加严重。

During the pumping construction, the pump operator should pay attention to the reading of the pumping pressure gauge at all times. Once the reading of the pressure gauge suddenly increases, the pump should be reversed for 2-3 strokes immediately, and then the pump should be straightened, and the pipe blockage can be eliminated. If the anti pump (positive pump) has been operated for several cycles and the pipe blockage has not been eliminated, the pipe should be removed and cleaned in time, otherwise the pipe blockage will be more serious.

泵送速度选择不当

Improper selection of pumping speed

泵送时，速度的选择很关键，操作人员不能一味地图快，有时欲速则不达。泵送时，由于管道阻力较大，此时应低速泵送，泵送正常后，可适当提高泵送速度。当出现堵管征兆或某一车混凝土的塌落度较小时，应低速泵送，将堵管消灭在萌芽状态。

When pumping, the choice of speed is very critical, the operator can not blindly map fast, sometimes speed is not up to. When pumping for the first time, due to the large pipeline resistance, it should be pumped at a low speed. After the pumping is normal, the pumping speed can be appropriately increased. When there is a sign of pipe plugging or the slump of a truck of concrete is small, it should be pumped at low speed to eliminate the pipe plugging in the bud.

余料量控制不适当

Improper control of surplus material

泵送时，操作人员须随时观察料斗中的余料，余料不得低于搅拌轴，如果余料太少，极易吸入空气，导致堵管。料斗中的料也不能堆得太多，应低于防护栏，以便于及时清理粗骨料和超大骨料。当某一车混凝土的塌落度较小时，余料可低于搅拌轴，控制在“S”管或吸入口以上，以减小搅拌阻力、摆动阻力和吸入阻力。本办法仅适用于“S”阀系列混凝土泵。

When pumping, the operator must observe the residual material in the hopper at any time, and the residual material shall not be lower than the mixing shaft. If the residual material is too small, it is easy to inhale air, resulting in pipe blockage. The material in the hopper should not be piled too much, and should be lower than the protective fence, so as to clean the coarse aggregate and super large aggregate in time. When the slump of a truck concrete is small, the surplus material can be lower than the mixing shaft and controlled above the "s" pipe or suction inlet to reduce the mixing resistance, swing resistance and suction resistance. This method is only applicable to "s" valve series concrete pump.

混凝土的塌落度过小时采取措施不当

Improper measures should be taken when concrete collapses

当发现有一斗混凝土的塌落度很小，无法泵送时，应及时将混凝土从料斗底部放掉，若贪图省事，强行泵送极易造成堵管。切忌在料斗中加水搅拌。

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

停机时间过长

Long downtime

停机期间，应每隔5-10min(具体时间视当日气温、混凝土塌落度、混凝土初凝时间而定)开泵一次，以防堵管。对于停机时间过长，已初凝的混凝土，不宜继续泵送。

During the shutdown period, the pump should be started every 5-10 minutes (the specific time depends on the temperature of the day, concrete slump and initial setting time of concrete) to prevent pipe blockage. It is not suitable to continue pumping the concrete that has been stopped for a long time and has set initially.

管道未清洗干净

Pipeline not cleaned

次泵送完毕，管道未清洗干净，会造成下一次泵送时堵管。所以每次泵送完毕一定要按照操作规程将输送管道清洗干净。

If the pipeline is not cleaned after the first pumping, the next pumping will be blocked. Therefore, after each pumping, the pipeline must be cleaned in accordance with the operating procedures.