Pumping failure refers to the phenomenon that the pumping can not continue when the concrete pump and pipeline are in good condition. The common pumping faults are pipe blockage and pump blockage. Among them, pipe plugging has great influence on construction and is difficult to deal with.

1.堵管的征兆

1. Signs of pipe blockage

在刚刚出现堵管征兆时，应及时采取措施，这对于防止堵管非常重要。在正常情况下，泵送油压高值不会达到设定压力，正常的泵送循环自动停止，主油路溢流阀发出溢流的响声，就表明已经发生了堵管。这时，只要打开反泵按钮，使两缸各进行一、二个冲程的反泵循环，把管道中的混凝土吸回一部分到料斗后，通常就能排除堵塞。有时候这种反泵操作要进行多次才有效。如多次反泵仍不能恢复正常循环，表明已经堵管。

It is very important to take timely measures to prevent pipe plugging when the symptoms of pipe plugging just appear. Under normal conditions, the high value of pumping oil pressure will not reach the set pressure, the normal pumping cycle will stop automatically, and the overflow sound of the main oil circuit relief valve indicates that the pipe blockage has occurred. At this time, as long as the anti pump button is turned on to make the two cylinders carry out one or two stroke anti pump circulation respectively, and part of the concrete in the pipeline is sucked back to the hopper, the blockage can be eliminated. Sometimes this kind of anti pump operation has to be carried out many times to be effective. If the pump can not return to normal circulation for many times, it indicates that the pipe has been blocked.

2.堵管部位的判断

2. Judgment of plugging position

发生堵管后，应一边进行泵送—反泵操作，一边让其他人员沿着输送管路寻找堵塞部位。一般情况是从泵的出口开始，未堵塞的管段会剧烈振动，而堵塞部位以后的管路是静止的。还可用木锤敲打检查，凭手感和声音判断堵管部位。锥管、弯管都易发生堵管。在长距离水平输送时，如有管接头漏浆，它后面的直管也容易堵塞。

In case of pipe blockage, the pumping anti pumping operation should be carried out at the same time, and other personnel should look for the blockage along the pipeline. Generally speaking, starting from the outlet of the pump, the non blocked pipe section will vibrate violently, while the pipe after the blocked part is static. You can also use a wooden hammer to knock and check, and judge the pipe plugging position by hand feeling and sound. Both taper pipe and bend pipe are easy to be blocked. In long-distance horizontal transportation, if there is slurry leakage at the pipe joint, the straight pipe behind it is easy to be blocked.
               

3.堵管的处理方法

3. Treatment of pipe blockage

在一边进行泵送—反泵操作，一边沿管路检查时，可以用木锤敲打被认为是堵塞的部位，有时能使堵塞的骨料瓦解而恢复畅通；若敲打无效，不准再用铁锤或其它可能伤害管道的物件重击。如堵管部位判断准确，只要把堵塞段管件拆下，其中已堵塞的混凝土，再装回去，即可继续泵送。如果堵管部位离管道未端较远，堵塞段被清理后回装到管路，由于这段空管的气塞作用，也会造成再次堵管。在这种情况下，应将堵管段以后的管道混凝土用气洗和水洗，再接管泵送。管线较长时，可分段拆洗。

During the pumping reverse pump operation and the inspection along the pipeline, the wooden hammer can be used to knock the parts that are considered to be blocked, sometimes the blocked aggregate can be disintegrated and unblocked; if the knocking is invalid, it is not allowed to use the hammer or other objects that may damage the pipeline. If the position of pipe plugging is judged accurately, as long as the pipe fittings in the plugging section are removed, the blocked concrete is removed, and then the concrete is put back, the pumping can continue. If the plugging part is far away from the end of the pipeline, the plugging section will be cleaned and installed back into the pipeline. Due to the air plugging effect of the empty pipe, the pipe will be plugged again. In this case, the pipe concrete after the pipe blocking section shall be removed by air washing and water washing, and then the pipe shall be pumped. When the pipeline is long, it can be removed and washed in sections.

4.防止泵送故障的措施

4. Measures to prevent pumping failure

要有合理的施工布置，包括输送管道、混凝土泵及供料系统的合理布置；泵送混凝土的配合比要合理，质量要好；保持泵机良好的工作状况，料斗、S 管内无干结的混凝土积渣，混凝土流道畅通；S 阀、出料口等部位密封良好；及时更换磨损件和调正磨损间隙；按规定做好维护保养工作；泵送中断不要太长；正常操作，不违规操作；作好输送管道的维护工作，不使用严重损坏的或未清洗干净的管件。

There should be reasonable construction layout, including the reasonable layout of conveying pipeline, concrete pump and feeding system; the mix proportion of pumping concrete should be reasonable and the quality should be good; the pump should be kept in good working condition, there should be no dry concrete slag in hopper and S pipe, and the concrete flow channel should be smooth; s Valve, outlet and other parts are well sealed; timely replace wear parts and adjust wear clearance; do maintenance work according to regulations; pump interruption should not be too long; normal operation, no illegal operation; do maintenance work of transmission pipeline, do not use seriously damaged or not cleaned pipe fittings.