Causes and preventive measures of concrete pump blocking pipe:
1, improper operation can easily cause plugging:
1.1 operators do not concentrate
Pump operating personnel in pump construction should concentrate on, always pay attention to pumping pressure gauge readings, once found a sudden increase of pressure gauge readings should be immediately 2-3 against the pump stroke, then is the pump blockage can be ruled out. If the pump has been carried out (the pump is a few operating cycle, has not yet ruled out the pipe should be promptly removed pipe cleaning, otherwise it will be more serious blockage.
1.2 improper pump speed
Pump, the choice of speed is the key, the operator can not blindly map fast, sometimes haste is less than. For the first time pumping, due to the greater resistance of the pipeline, at this time should be low speed pumping, pumping normal, can be appropriately increased pumping speed. When plugging a sign or a car slump of concrete is small, should slow pumping, the plugging nipped in the bud.
1.3 more than the amount of control is not appropriate
When pumping, the operator must observe at any time in the hopper material, the material should not be lower than the stirring shaft, if the material is too small, very easy to breathe in the air, leading to plugging. Hopper material can not be piled too much, should be lower than the fence, in order to facilitate the timely clean-up of coarse aggregate and super aggregate. Is small when a car slump of concrete, I expected to be lower than the stirring shaft, control the "S" tube or intake above, to reduce the stirring resistance, swing resistance and inhalation resistance. This procedure applies only to the "S" valve series concrete pump.
1.4 the collapse of concrete measures taken do not spend hours Dangdang found a small bucket of concrete slump, unable to pump, should be the concrete from the hopper bottom out, if the temptation to save trouble, forced pumping easily cause plugging. Avoid mixing water in the hopper.
1.5 Long downtime
During the shutdown, should every 5 ~ 10min (depending on the specific time of day temperature, concrete slump, concrete setting time) to open the pump once to prevent pipe blockage. For too long downtime, has been the beginning of concrete, should not continue pumping.
1.6 pipeline is not clean
The last pumping is completed, the pipeline is not clean, will cause the next pump when the pipe. So every time the pump must be completed in accordance with the operating rules of the pipeline cleaning.
2, pipe connection causes the pipe:
Pipe connection error can easily lead to pipe blockage. The following principles shall be followed:
Piping layout should be according to the shortest distance, at least the elbow and the maximum elbow to the pipe, as far as possible to reduce the resistance, also reduces the possibility of plugging.
Pump outlet cone pipe, not directly connected to the elbow, at least should be connected to the 5mm straight pipe, then take the elbow.
When the pump is in the middle of the pipe, it can only be added one time, and the water is used to lubricate the inner wall of the pipe, so as to do the air side by side.
Vertical downward pipeline, the outlet should be equipped with isolation devices to prevent plugging.
When the pump is delivered, the length of the horizontal pipe shall not be less than 15% of the length of the vertical pipe. When the shutdown time is more than 5min, the valve should be closed to prevent the backflow of concrete, leading to plugging. From the horizontal to vertical 90 degree bend, bending radius should be greater than 500mm.
3, concrete or mortar segregation caused by pipe:
When concrete or mortar meets water, it is easy to cause segregation. Sometimes pumping mortar, then the occurrence of plugging phenomenon, because mortar and direct contact with the water in the pipes, the mortar caused by segregation, preventive measures are: wet water pipe before the pump after the lowest point from the pipe joint release, will let go all over the water, or pumping, before pumping mortar, put a sponge ball, mortar and water will separate.
When the pump is finished, it must be put into a sponge ball, which separates the water from the concrete.