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. Signs of pipe blockage
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. Judgment of plugging position
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. Treatment of pipe blockage
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. 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.