clean
Cleaning requires that all parts of the concrete mixing station should be kept free of oil sludge, dirt and dust, especially the cleanliness of the surface of the motor and reducer, and the normal heat dissipation of the machinery. concrete mixing
Fastening
Fastening is to timely check and fasten the connectors of each part of the concrete mixing plant. The vibration generated during the mechanical operation is easy to loosen the connectors. If not tightened in time, not only oil leakage, air leakage, water leakage, electricity leakage, etc. may occur, but also the loosening of bolts at some key parts will change the force distribution of the original design components, which may cause deformation of components, or fracture and separation of parts, leading to operation failure and mechanical accidents.
adjustment
Adjustment is to timely check and adjust the relative relationship and working parameters of many parts of the concrete mixing plant machinery. The station maintenance method, especially the flexibility and reliability of key components, should be properly adjusted to prevent accidents.
lubrication
Lubrication is to add or replace lubricating oil regularly according to the specified requirements, so as to maintain good lubrication between moving parts of machinery, reduce wear of parts and ensure normal operation of machinery.
protect
The protection is to prevent the concrete mixing plant from moisture, rust, acid and corrosion of mechanical parts and electrical equipment. In particular, the surface of the machine shall be painted or coated with anti-corrosion materials such as grease.
drive system
The transmission system is driven by two motors to two right angle planetary reducers through belt. The reducers drive the two mixing shafts to rotate through spline shafts. The synchronization of the two mixing shafts is realized by couplings. The reducer has the characteristics of stable transmission, convenient installation, low noise, etc.
Mixing system
The mixing system is composed of mixing tank and mixing device.
Mixing tank
The mixing tank is composed of cylinder and lining plate.
In order to avoid wear on the inner side of the cylinder, the whole inner cavity of the cylinder is equipped with wear-resistant lining plates, which can be replaced according to the wear condition of the lining plates. There is a discharge port under the cylinder to discharge the concrete in time.
Mixing device
The mixing device is composed of mixing shaft, mixing arm, mixing blade and shaft end sealing device. The mixing arm and the mixing shaft are connected and fixed through a connecting sleeve and a bolt. The mixing blade and the mixing arm are connected by bolts through long holes. By adjusting the position of the mixing blade, the gap between the blade and the lining plate is not more than 5mm, which can not only slow down the wear of the blade and the lining plate, discharge cleanly, but also reduce energy consumption and noise, so that the mixer can work smoothly and is not easy to jam.
Shaft end sealing device
The shaft end sealing device consists of four seals, which are labyrinth seal, plane seal ring seal, U-ring seal and floating seal in the order from inside to outside. Through timely oil supply, the wear surface of each sealing element in the sealing chamber can be well lubricated. Therefore, the device can seal the shaft end, which is safe and reliable, and also reduces the maintenance cost.
Unloading system
The system consists of a discharging mechanism, a discharging door, etc. The unloading mechanism is divided into hydraulic unloading and pneumatic unloading (special order).
Hydraulic unloading mechanism
The hydraulic unloading mechanism includes hydraulic power pack, rocker arm, hydraulic cylinder, etc.
The mechanism is operated by a single hydraulic cylinder. Its working principle is that the hydraulic power drives the rocker arm through the hydraulic cylinder to make the discharge door rotate at a certain angle. Inductive proximity sensors are installed at the opening, middle and closing positions of the material door. By adjusting the position of the middle position proximity sensor, the size of the opening material door can be adjusted to meet the needs of users with different material receiving capacities. The hydraulic power pack is equipped with a manual pump. When the mixer is suddenly powered off during operation, or the electric pump cannot work normally, in order to unload the concrete in the mixing tank and prevent it from solidifying in the mixing tank, the manual pump can be used to open the material gate to clean the mixing tank.
Pneumatic unloading mechanism
Pneumatic unloading mechanism includes air cylinder, rocker arm, solenoid valve, etc. This part shall be specially ordered
The air source for pneumatic unloading is generally provided by the air pump uniformly used in the mixing station (building), and the air pressure is generally required to be ≥ 0.5MPa. This mechanism is operated by two air cylinders, which are installed at both ends of the mixing tank respectively and driven synchronously, so that the opening and closing of the unloading door are more reliable. The three position five way electric control reversing valve controls the cylinder to open or close the discharge valve to realize the discharge of the mixer. Through microcomputer electrical control of cylinder stroke, the size of opening material door can be adjusted to meet the needs of users with different material receiving capacities.
Discharge door
The discharge door is processed by assembling weldments.
The bearings at both ends of the discharge door shall be maintained carefully, and oil shall be injected after cleaning the mixing tank every time. A sealing strip is installed between the discharge door and the mixing tank. The sealing performance of the discharge door can be achieved by adjusting the height of the gasket of the bearing seat.
Oil supply and lubrication system
The mixing host adopts a variety of oil supply and lubrication methods, mainly including shaft end electric thick oil pump oil injection lubrication, gearbox oil immersion lubrication and bearing oil gun oil injection. The electric thick oil pump is equipped with a low level alarm device to remind the user to fill grease into the reservoir in time.
Unloading handle
The unloading handle is a group of weldments. In case of sudden power failure during the operation of the mixer, in order to unload the concrete in the mixing tank and prevent it from solidifying in the cylinder, the cylinder joint pin shaft can be disconnected, and the unloading handle can be used to pull the shaft end of the unloading door to open the door so as to clean the mixing tank.
Mixing device
It is mainly composed of mixing drum and its auxiliary supporting parts. The mixing drum is a concrete loading container, which is made of wear-resistant thin steel plate. In order to automatically load and unload concrete, its inner wall is welded with spiral blades of special shape. When rotating, the concrete moves along the spiral direction of the blade, and is mixed and stirred in the process of continuous lifting and turning. In the process of feeding and transportation, the mixing drum rotates forward, and the concrete moves inward along the blade. When discharging, the mixing drum reverses, and the concrete is discharged outward along the blade. The mixing drum is rotated by hydraulic drive device. The loading capacity is 3-6 cubic meters. The concrete mixer truck of is generally driven by the automobile engine through the power output shaft to drive the hydraulic pump, and then driven by the hydraulic motor driven by high-pressure oil to drive the mixing drum. The truck mounted auxiliary diesel engine is used to drive the hydraulic pump to drive the hydraulic motor when the loading capacity is 9-12m3. The blade is the main part of the mixing device, and damage or serious wear will lead to uneven concrete mixing. In addition, if the angle of the blade is not properly designed, the concrete will segregate.
If the concrete mixer does not produce for a short time during normal operation, the mixing motor should be kept in normal operation and the operation of other electrical parts should be cut off. The material cut-off switch and the water pump button of the water supply system can also be operated to stop the material supply and water supply of the material supply system while maintaining the operation of other parts.
5. In normal production, in case of emergency, press the "Emergency Stop" button when all the machines have to be shut down, and then all the motors stop running. Concrete mixing, however, will cause unnecessary trouble to restart the machine because various materials have not been transported completely. The stabilized soil mixing plant manufacturer believes that in addition to paying attention to the safety of the machine and the supply of relevant materials, it is necessary to improve the sense of responsibility of the operators and strive to maintain the normal operation of the machine.
The requirements of the concrete mixer for its lubricating oil are: it has certain viscosity and viscosity temperature characteristics, low freezing point, good overall understanding of the machine, no mechanical impurities and moisture, and is not corrosive and abrasive substances. The common gasoline engine lubricating oil is numbered with a kinematic viscosity of 100c, including No. 6, No. 10, No. 15, No. 8 thickening, No. 8 low setting, the higher the grade, the greater the viscosity, and its quality indicators should meet the national standards.
The selection of gasoline engine lubrication berth depends on the environment of the area of use, the type of gasoline engine and the degree of wear. The machine oil with larger brand shall be selected for the machines in the stabilized soil mixing station with higher temperature, greater wear and tear; For the internal combustion engine with low temperature, new engine and high speed, the engine oil with lower brand shall be selected.
The lubricating oil used is very pure and clean, without impurities, dust, etc., to prevent damage to the lubrication and the surface of concrete mixer parts. The amount of lubricating oil shall be sufficient, and the oil layer added to the oil tank or oil pool shall reach the water level indicated by the mooring mark.
Before the equipment in the mixing station is shut down, it shall be unloaded first, and then all switches and pipelines shall be closed in order. All cement in the spiral pipe shall be transported out, and no materials shall be left in the equipment pipe of the mixing station; In freezing season, the water pump, additive pump, water tank and additive tank shall be drained, and the mixing plant equipment water pump and additive pump shall be started to work within 1-2 minutes; After the mixing plant equipment is shut down, all parts of the mixing plant equipment shall be cleaned and weighed accurately. The concrete mixer shall be cleaned in place.
Because during construction, some raw materials or semi-finished products will fall around the conveyor belt or mixing tank. If they are not cleaned in time, they will accumulate together, thus affecting the normal operation of the entire conveyor belt. Therefore, when the concrete mixing plant is running, it should be cleaned constantly. When producing cement and stabilized soil gravel, it should be cleaned immediately as long as it is stopped.
(1) Clean the blades of the concrete mixer timely after each mixing to remove the dirt on the blades of the mixer. Add lubricating oil between the bearing and blade of concrete mixer, and between the blade and blade handle of concrete mixer. Rust removal and anti rust treatment shall be carried out for the mixer blades in time to avoid rust and corrosion of concrete mixer blades due to untimely maintenance.
(2) Regularly check the abrasion and consumption of the concrete mixer blade and the welding position between the concrete mixer blade and the blade handle, record the abnormal phenomena found and select corresponding solutions. In addition, it is also necessary to check whether the welding point of the mixer blade is connected to the bottom, so as to prevent casualties caused by electric leakage. The distance between the concrete mixer blade and the lining plate is also one of the data that needs to be carefully checked and recorded.
(3) Before the start of each shift, the concrete mixer should be allowed to idle for two to three minutes to check whether the concrete mixer blades are firm and normal. If there is abnormal sound or parts fall during the operation, it should be quickly eliminated with attention to safety. Maintenance personnel and construction personnel shall keep away from the outlet direction of the concrete mixer as far as possible during idling to avoid casualties caused by flying parts.
(4) In the process of concrete mixing, pay close attention to the sound, speed, strength and other conditions of the mixer blades to prevent fracture and other accidents.
(5) Strictly control the feeding specification of the concrete mixer, and it is better to screen before feeding. During the selection of concrete materials, no matter the size of concrete formula and material specifications, the properties of concrete materials such as pH should also be paid attention to, so as to avoid unnecessary corrosion of concrete mixer blades caused by improper use of materials.
(6) The concrete mixer blades shall be subject to wear resistance treatment regularly to increase the wear resistance of the mixer blades. Timely adjust the distance between the concrete mixer blade and the lining plate as required. In wear-resistant treatment, appropriate treatment methods shall be selected according to different positions of concrete mixer blades. The strength and wear resistance of concrete mixer blades can be increased by adding manganese and nano to the concrete mixer blades.
(7) The Construction Project Department needs to arrange personnel to maintain the concrete mixer and other construction machinery on the construction site, and maintain the concrete mixer blades and secondary maintenance in a timely manner. Establish a digital registration system for maintenance, and at the same time, the management personnel on the construction site shall timely understand the use status of construction machinery.
