Little knowledge of pump truck blocking, necessary for pump operators

All pumpers may encounter this problem, blocking the pipe!

A worldwide problem, very disturbing, not only affected the progress of the project, but also affected the working mood of the pumpers.

There are many reasons for blocking pipes, man-made, machines, etc. Today, I will talk about the problem of blocking the pump trucks.

Blocking reasons:

Under normal circumstances, commercial concrete forms a columnar fluid in the center of the pumping pipeline and flows in a suspended state.

The surface of the fluid is covered with a layer of cement slurry. The cement slurry layer acts as a lubricant to contact the wall of the pipe, and there is basically no relative movement between the aggregates.

When the movement of some aggregates in the coarse aggregate is blocked, the movement speed of the subsequent aggregate gradually slows down due to the impact, resulting in the formation of aggregate in the pipeline, the mortar supporting the coarse aggregate is squeezed away, and the remaining gap Filled with small aggregates.

In this way, the aggregate density increases, causing the aggregates in this section of pipe to expand radially along the pipe, the cement slurry lubrication layer is destroyed, the movement resistance increases, and the speed becomes slower until the movement stops and blockage occurs.

Judgment and elimination of blocked pipe position:

1. Blockage at the inlet:

The pumping action and hydraulic system are normal, there are no abnormal sounds and vibrations, there is a large aggregate or agglomeration in the hopper, and it is stuck or arched at the feed port and blocked.

Remedy: Run the pump in reverse to destroy the agglomeration, return the commercial concrete to the hopper and stir again, and then pump it forward. If it does not work, it needs to be manually cleaned up and eliminated.

2. Blockage at the outlet of the distribution valve:

The action of the pumping system was suddenly interrupted, there was an abnormal noise, the equipment had strong vibrations, but there was no corresponding vibration in the pipeline.

Remedy: Pour 15 ~ 30L cement slurry into the hopper, and repeat the positive and negative pumps to force the passage to open. If this method is not effective, it can only be eliminated manually, remove the connecting pipe, and remove the debris in the valve.

3. Blockage at the S-pipe valve:

The clogging at the S pipe valve is gradually formed. The main reason is that after the commercial concrete is pumped, it is not flushed with high pressure water in time, which causes the commercial concrete to remain in the S pipe.

Exclusion method: After the pumping of the commercial concrete, the pump body and the S pipe must be washed with high-pressure water. When rinsing is not effective, you can use tapping to remove the residue until it is completely clean.

4. Blockage of commercial concrete pipelines:

When the conveying pressure gradually increases, the hopper level does not drop, the pipe outlet does not discharge, the pump vibrates, and the pipe is accompanied by strong vibration and displacement, it can be determined that the pipe is blocked.

Judgment of blocked parts: Blocking generally occurs in curved pipes, tapered pipes, and areas with vibration. At this time, you can use a small hammer to hit along the pipeline. The dull sound is the blockage; the crisp sound is normal. Listen with your ears, rustling is normal, and harsh ears are blocked.

Exclusion method: When a pipe blockage occurs, the method of repeating the forward and reverse pumps should be adopted immediately, and the commercial concrete at the pump outlet should be gradually sucked back to the hopper and remixed before being transported. It can also be tapped with a wooden hammer, combined with forward and reverse pumps, to make it clear;

When the above measures are not effective, it means that the blockage is serious. After finding out the blocked section, remove the pipe, blow it with high-pressure air or hammer, or wash it with high-pressure water. After it is completely cleaned, connect the pipeline and continue pumping the commercial concrete.

Measures to prevent blockage of pumped commercial concrete:

1. When installing and designing pipes, avoid 90 ° and S-bends as much as possible to reduce the resistance of pumping commercial concrete and prevent blockage.

2. In order to ensure the continuity of the pumped commercial concrete operation and the quality of the commercial concrete pouring, the interval between operations should not be too long to prevent blockage. If the interval is long for some reason, you should start the pump or reverse and forward pump several times every 5 to 10 minutes to prevent blockage.

3. The pumped commercial concrete shall be strictly designed in accordance with the pumped commercial concrete design mix ratio, and the slump shall be strictly controlled.

4. The particle size of the selected aggregate must meet the requirements, and generally should not be larger than 1/4 of the diameter of the conveying pipe.

5. There are two ways to lubricate the pipelines of the boom concrete pump truck before pumping commercial concrete:

ATraditional method: first lubricate the pipeline with clean water, and then send a certain amount of mortar before pumping the commercial concrete to prevent blockage. The cost of this method is higher (400 yuan / time).

B. Scientific method: first use a pipe-lubricant special for boom pump trucks (commonly known as “good companion for boom pump trucks” in the market) to lubricate the pipelines, and then start pumping the commercial concrete. This method is easy to operate and the cost is very low. At present, many large construction sites, commercial concrete stations, boom truck rental companies, etc. are selected. The research and development of the boom pump pump lubricating agent can be said to be a huge revolution in the pumping technology of commercial concrete in this century! The future promotion prospect is huge!

6. In the hot summer, the wet straw bag should be used to cover the pipeline to prevent the commercial concrete from falling too fast during the pumping process and causing the pipe to be blocked.