The phenomenon of cut-off of concrete pump and the problem of hydraulic system

It must be a problem for users that the concrete delivery pump is cut off in the process of use, so why is it cut off and what can be done to solve it? Today, let's share with you how to solve the problem of disconnection.

1. Shorten the reversing time and speed up the running speed of the main cylinder piston at the beginning of reversing.

2. The constant power plunger pump is controlled by electric proportion. Increase the displacement of the main oil pump to realize the rapid reversing of the distribution valve and reduce the time from reversing to starting to push the concrete.

3. Two proximity switches are set in the water tank between the oil cylinder and the concrete cylinder. The positions of the starting and cutoff point and the signal taking port are set according to the displacement of the main oil pump, the cylinder diameter and stroke of the main oil cylinder. The distance between the proximity switches is usually 5% ~ 10% of the total stroke. It is adjusted according to the actual situation of the concrete pump.

Concrete delivery pump is a kind of equipment for transporting concrete by pipeline. It is used for the transportation and supply of concrete in the construction of reinforced concrete structures. It is widely used in high-rise or super high-rise housing construction, tunnel and bridge construction. The use of concrete transportation can not only reduce the cost, but also save the construction time and standardize the construction site.

By studying the change law of the technical status of the concrete pump in the use process, and carrying out the necessary maintenance and maintenance before the mechanical parts have not reached the limit wear or failure, the service life of the concrete pump can be prolonged, the hidden dangers can be eliminated, the accidents can be prevented, and the smooth progress of the pumping operation can be guaranteed.

Next, according to the working experience of technicians, we will summarize the parts and contents that need key maintenance and repair in the use of concrete pump, so as to guide the operation and use of mechanical concrete pump customers.

Taking HBT concrete delivery pump as an example, its hydraulic system includes four parts: main pump oil circuit system, distribution valve oil circuit system, mixing oil circuit system and lubrication system. The maintenance and overhaul of the hydraulic system is the focus of the maintenance of the concrete transfer pump, mainly including the following points:

1. Hydraulic oil is not only a power transmission medium, but also a softener and coolant. When selecting, considering the working conditions, surrounding environment and role of the hydraulic system, the hydraulic oil should have appropriate viscosity, good lubricity, good oxidation resistance and good cleanliness. The normal hydraulic oil temperature is 20 ℃ ~ 60 ℃, and the high temperature limit is 70 ℃. It is recommended to drain the hydraulic system when the hydraulic oil is warm, so that the dirt in the hydraulic oil can be discharged with the oil: drain the oil as much as possible to prevent the mixing of old and new oil. After the oil is drained, flush the accumulation in the system with low viscosity hydraulic oil, and the hydraulic oil must contain preservatives to prevent rust on the metal surface just after the hot oil is drained. Replace the hydraulic oil after the oil pump and motor are removed for maintenance in case of failure. All links of hydraulic oil management and use must prevent oil pollution. The hydraulic oil drum shall be placed separately and covered with tarpaulin to prevent dust and water, and the oil drum shall be fully loaded to prevent the formation of condensate.

The oil filter and return oil filter of the main system of the hydraulic system shall be frequently checked for blockage. If blockage is found, all oil filters shall be cleaned or the filter element shall be replaced.

2. The main causes of hydraulic oil tank pollution are:

(1) Dust on the construction site.

(2) The oil tank is small, and the hydraulic oil is not fully precipitated before entering the oil pump again.

(3) The oil quantity of the hydraulic system is small, the turnover frequency increases accordingly, and the grinding of the hydraulic system increases due to pollutants. The mesh oil filter on the oil inlet pipe head in the hydraulic oil tank shall be cleaned regularly to ensure that the oil pump can absorb enough hydraulic oil at all times.