Precautions and preventive measures of concrete pump machinery

Fine stone concrete pump has been developed in the direction of high pressure and large displacement, in the high-rise building construction, it is necessary to take into account the pump in the stop of the pump back and its preventive measures. Backflow of concrete and its impact on the so-called "stop pump" system refers to the fine stone concrete pump in the pumping batch (non-stop mainframe) or after the completion of the work before the completion of the concrete conveying pump stop. In the normal operation of the main cylinder when the pump stops (the starting and ending points) vertical piping in high slump concrete (18 - 22mm), the gravity of the larger through the horizontal piping and concrete distribution valve back pressure to return, return transfer to the concrete distribution valve back return, return back to the pressure transfer to concrete piston, piston rod and then transferred to the master cylinder piston oil cylinder pushing movement, to prevent the master cylinder structure in and out of the main oil channel, using the three position four way valve surface can be achieved when the pump stops the master cylinder circuit in the main circuit system of unloading partition, main control anti pump three cylinder, four valve adopts the liquid control structure of spring reset, the slide valve function for type M. Its working principle is to stop the pump, hydraulic control oil pressure PK disappear.

Four position three way valve core is in the middle position with the displacement spring on both sides. At this time, the outlet of the valve is in the closing state, and the main oil pressure P is in the oil unloading state. By the stop valve. In some closed the main pumping system, dig four valve control master cylinder reversing also uses the three position four way valve structure, but the slide valve function is the use of "H" type. Although it meets the requirements of the closed loop system, it can not play the role of preventing the backflow of concrete. Better to use M type function. Can meet the requirements of the closed system, but also to prevent the concrete back. The concrete structure of the one-way valve closed to prevent backflow of locking of the hydraulic concrete back from the back pressure, its working principle is to stop the pump, solenoid valve in the work position, the back pressure PK by the master cylinder four valve cylinder to produce concrete back (two), will be pushed to the right position of the spool spindle and, through the shuttle valve, solenoid valve after the role of the spring on the valve cavity. Because the one-way valve is the DF type right angle type, the main cylinder back pressure and is in the unloading state of the main system is separated from. Using sequential valve main core to send off the main circuit. In the main system sequence valve motion sequence, the sequence valve core in concrete pump when closed, the master cylinder oil inlet and unloading system is separated, the principle is in the current structure, one-way valve and the control circuit does not exist.