In addition to high reliability, the concrete pump truck must also do a good job in the inspection and maintenance of the pump truck and master the emergency treatment plan for the failure of the pump truck, otherwise it will lead to tragedy. This is not true. Recently, Xiaobian encountered a tragedy of concrete condensation of the conveying pipe caused by inadequate maintenance and inexperienced operators. Let’s talk about the causes and consequences of this accident.
On the last day of the national day, I went to the commercial mixing station where I worked before. As soon as I entered the door, I found that the elbow behind the hopper of the pump truck was disassembled. After inquiry, it was learned that during the pumping process, the swing oil cylinder and the swing handle of s swing valve fell off, resulting in the pump truck unable to pump, and the pump truck boom was retracted and returned to the company for treatment without any treatment on site.
Next, the operator plans to do two things for emergency treatment. One is to repair the connecting plate. However, during the maintenance process, it was found that only a small section of the keyway was in contact with the spline of the s swing valve at the end of the swing handle falling off, resulting in the deformation of the keyway and spline, which could not be replaced.
In case of necessity, the second scheme is adopted, and the on-board pump is directly connected to the pump truck delivery pipe to see whether the concrete in the delivery pipe can be flushed out in reverse. However, due to too long time, the concrete in the conveying pipe coagulated, which also ended in failure.
In the process of back flushing, due to the blocking of concrete and the excessive pressure of the conveying pipe, the 5-arm conveying pipe was broken, and the stones washed out by high pressure broke the side window glass of Delong dump truck parked next to it.
This operation is very dangerous. After the conveying pipe cannot withstand high pressure, the pipe will explode. The stones ejected by high pressure and the fragments that burst the conveying pipe are like shrapnel, which will cause extremely serious consequences to personnel. Strongly prohibited! Strongly prohibited! Strongly prohibited! Say important things three times.
After the above two methods failed, we can only dismantle all the delivery pipes to clean the concrete in the pipes. It is very hard to do so, which is also the biggest headache for each pump truck operator. The maintenance of pump truck due to failure and shutdown will also cause a lot of losses. What is the reason? Let’s follow the accident and see what the problem is.
The main reason why the swing handle of swing cylinder and s swing valve falls off is that the fastening nut falls off. The falling off of the nut does not happen overnight, which also shows that the pump truck is lack of maintenance and repair at ordinary times. If it is checked frequently, such faults generally will not occur.
Generally, after the pump truck fails to pump and cannot be repaired in a short time, the concrete in the conveying pipe shall be drained immediately, otherwise the conveying pipe will be scrapped. In this accident, after the failure, the pump truck operator did not do so, but retracted the boom and drove the vehicle back to the factory for treatment. The delayed time led to the concreting of the conveying pipe.
Xiaobian’s experience is to operate according to the following methods. Of course, it may not be too comprehensive. If you have better experience, you are welcome to share with us.
When the concrete still has fluidity, disassemble the elbow behind the hopper, and then vertically discharge the boom from the conveying pipe by its own gravity. However, the concrete in the flat pipe still needs to be disassembled and discharged manually.
If the above methods cannot make the concrete in the pipe discharge automatically, the pipe can be removed from the elbow behind the hopper towards the boom to minimize the blocking length of the conveying pipe and reduce the loss and later workload. However, it should be noted that the boom should be placed flat when removing the pipe to prevent personal injury caused by the spraying of concrete in the pipe due to gravity.
Wash the concrete in the delivery cylinder and s swing pipe with the high-pressure water gun or on-site water pipe brought by the pump truck to prevent the concrete from solidification. Because the s swing valve cannot work, when flushing another conveying cylinder, pry the s swing valve with a crowbar in the hopper to move it again, and then flush with a water gun.
The concrete pump truck needs to have very high reliability, and the operator must have the experience in handling the emergency plan. Because in the process of construction, in case of failure and failure to pump, the direct and indirect losses will be very serious. All pump truck operators shall master this experience and do a good job in the daily maintenance of pump truck. I also hope that auto enterprises can do a good job in this aspect of pre-sales training and improve their brand value.
The family members of the workers who died due to the sudden spraying of commercial concrete by the pump truck were compensated 510000
Dance like a nose, cement pump truck operation safety
