Working principle of concrete mixer truck transport vehicle
With the rapid development of concrete production and construction technology, some countries have gradually adopted the method of centralized concrete mixing and commercial supply, and the concrete is provided by special concrete mixing station and transported to various construction sites by concrete mixing transportation vehicles. The structure principle and maintenance of the concrete mixer truck are briefly introduced.

Composition and working principle of concrete mixing truck
The concrete mixing truck is composed of automobile chassis and special equipment for concrete mixing transportation. The chassis of the concrete mixing truck produced in our country mostly adopts the second kind universal chassis provided by the whole truck manufacturer. Its special mechanism mainly includes the force extractor, the support before and after the stirring tube, the reducer, the hydraulic system, the stirring tube, the controlling mechanism, the cleaning system and so on. Working principle: take out the power of the car chassis through the force extraction device, and drive the variable pump of hydraulic system, convert the mechanical energy into hydraulic energy and pass to the quantitative motor, and the motor drives the reducer again, and the mixer is driven by the reducer to mix the concrete.
1. 1. Force extraction device
The domestic concrete mixing truck adopts the main engine to pick up the force. The function of the force extraction device is to remove the engine power by controlling the force extraction switch and drive the stirring cylinder through the hydraulic system. The agitator cylinder rotates forward in the process of feeding and transportation, so as to facilitate feeding and mixing of concrete. When discharging, it rotates backward, cutting off the power connection with the engine after the end of work.

1. 2 hydraulic system
The power of the motor taken out by the force extractor is converted into hydraulic energy (displacement and pressure), and the mechanical energy (speed and torque) is output through the motor, providing power for the rotation of the stirring tube.
1. 3 speed reducer
Slow down the speed of the motor output in the hydraulic system and pass it to the agitator.
1. 4 control mechanism
A. Control the rotation direction of the agitator barrel so that it will rotate forward in the process of feeding and transportation, and reverse in the process of discharging.
B. Control the speed of stirring tube
1. 5 stirring device
It is mainly composed of stirring tube and supporting parts. The agitator tube is the concrete loading container, which is made of high quality wear-resistant steel sheet. In order to automatically load and unload the concrete, its inner wall is welded with specially shaped spiral blade. As the concrete moves along the spiral direction of the blade, it is mixed and stirred in the process of continuous lifting and turning. In the process of feeding and transportation, the stirring tube rotates positively, and the concrete moves inward along the blade. When discharging, the stirring tube reverses and the concrete is discharged outward along the blade. The rotation of stirring tube depends on the hydraulic drive device. The concrete mixing transport vehicle with a loading capacity of 3 ~ 6 cubic meters generally adopts the hydraulic pump driven by the motor engine through the power output shaft, and the mixing barrel driven by the hydraulic motor driven by the high-pressure oil, while the hydraulic pump driven by the on-board auxiliary diesel engine with a loading capacity of 9 ~ 12 cubic meters. The blade is the main part in the mixing plant. The damage or serious wear will cause the uneven mixing of concrete. In addition, if the blade Angle is not reasonable, concrete will be isolated.
1. 6 cleaning system
The main function of the cleaning system is to clean the stirring tube, and sometimes it is used for dry stirring in transit. The cleaning system also cools the hydraulic system.
Maintenance and repair of concrete mixing truck
As a transport vehicle, the concrete mixer truck must comply with the regulations of the ministry of communications (motc) in order no. 13, 1990 in terms of maintenance and repair and implement the maintenance and repair system of “regular inspection, mandatory maintenance and repair as required”. In this premise, combined with the actual situation of the concrete mixing truck, good maintenance and repair. In the aspect of daily maintenance, the concrete mixing truck should not only maintain the engine, chassis and other parts, but also do the following maintenance.
2. Clean concrete storage tank (mixing barrel) and inlet and outlet
Since the concrete will solidify into hard blocks in a short period of time and has a certain corrosiveness to steel and paint, cleaning the concrete adhered to the concrete storage tank and the inlet and outlet of the concrete tank is a daily maintenance work that must be done seriously. Among them:
A. Rinse the inlet with water before each charge to keep it moist while charging.
B. Fill the washing water tank with water when charging the materials;
C. Rinse the inlet after charging and clean the remaining concrete near the inlet.
D. After unloading at the construction site, flush out the feed tank, and then add the cleaning water to the concrete storage tank (30-40 L); Keep the concrete tank turning slowly on the return trip.
E. Be sure to remove the sewage from the concrete storage tank before loading next time.
F. Clean the concrete storage tank and the area around the inlet and outlet thoroughly every day.
As long as the above work is not carried out seriously, it will bring great trouble to the future work.
2. Maintain the drive
The driving device is used to drive the rotation of concrete storage tank. It is composed of force extractor, universal shaft, hydraulic pump, hydraulic motor, control valve, hydraulic oil tank and cooling device. If this part stops working due to fault, the concrete storage tank will not be able to rotate, which will cause the in-car concrete to be scrapped, and even cause the whole concrete to condense in the tank, causing the concrete mixing truck to be scrapped. Therefore, whether the drive device is reliable is a problem that must be paid great attention to in use. In order to ensure the drive device is intact and reliable, the following maintenance work should be done:
A. The universal rotating part is the part with multiple faults, grease should be added on time, and wear should be checked frequently to repair and replace in time. The fleet should have a spare universal shaft assembly that can be restored in a matter of minutes in case of failure.
B. Keep hydraulic oil clean. The working environment of the concrete mixing truck is bad, and sewage sediment must be prevented from entering the hydraulic system. Hydraulic oil should be changed regularly according to the manual. If water or sediment is found in the hydraulic oil during inspection, the hydraulic system shall be shut down immediately to clean and replace the hydraulic oil.
C. Ensure the hydraulic oil cooling device is effective. Should regularly clean the hydraulic oil radiator, to avoid the radiator blocked by cement, check whether the radiator electric fan operation is normal, to prevent the hydraulic oil temperature exceed the standard. Hydraulic part as long as the hydraulic oil clean, general faults few; But production manufacturer is different, service life is different.
2. Pay attention to tire maintenance
In addition, our company produces: oil tanker, sprinkler truck, garbage truck, sewage truck, dump truck, truck, garbage truck, coach truck, overhead working truck, bulk cement truck for powder material, chemical liquid truck, cement mixer, etc.