Concrete batching plant is an important equipment for the production of concrete in construction projects. Its operating efficiency and stability directly affect the construction progress and project quality. Due to the long-term high-frequency flow and mixing of aggregates, cement and other materials, the equipment works in harsh environments such as dust, vibration, temperature difference, etc., and key parts are prone to wear, loosening or calibration drift. Therefore, it is important to formulate and implement a systematic maintenance plan. Structured inspection and maintenance plans can significantly reduce the failure rate of equipment and reduce the impact of downtime on production.
Accurate weighing, smooth material flow and efficient stirring depend on the good condition of each component. Preventive maintenance maintains the accuracy of stirring blades, sensors and weighing systems. When there is a deviation in the measurement system of the concrete mixing plant, the concrete mixing ratio cannot be guaranteed, which directly affects the safety of the engineering structure. For example, the weighing error of gelling materials should be controlled within ±1%, and the measurement error of sand and stone materials should not exceed ±2% – the maintenance of these accuracy cannot be separated from daily maintenance and calibration.
At present, environmental protection supervision strictly controls the dust and sewage discharge of mobile batching plants. The damage of the dust collector on the top of the warehouse, the unsealed belt, and the blockage of the dust removal filter bag will cause a large area of dust in the factory area; pipeline leakage and indiscriminate discharge of flushing wastewater will trigger environmental protection law enforcement penalties. The maintenance list includes dust removal systems, wastewater recovery equipment and sealing devices into the normal inspection, and regularly cleans up and replaces accessories to meet the requirements of environmental protection and compliant production.
Under normal use, the design service life of most concrete plants is 10 to 15 years. However, if the preventive maintenance of the system is carried out, the equipment can operate reliably for more than 20 years. On the contrary, if it is only repaired after the failure, the equipment will deteriorate faster and the service life will be significantly shortened.
Prevention priority principle; replace emergency repair after failure with regular inspection, maintenance and calibration, and divide the cycle of all inspection items in advance to eliminate “repair if it is broken”;
Cycle classification principle; daily, weekly, monthly, quarterly and annual maintenance is divided according to the wear speed of the equipment, and the inspection cycle of high-frequency loss parts is shortened;
The principle of fixed posts and responsibilities; divide the three-level positions of operators, full-time maintenance technicians and equipment supervisors, and clarify the maintenance projects corresponding to each position, and the responsibility can be traced back.
The on-site operator (the main body of daily maintenance implementation) is responsible for basic cleaning, visual inspection, simple lubrication, hidden danger records before the start-up and after production of each shift, and fill in the daily maintenance record form;
Full-time maintenance technician (weekly/monthly maintenance executive body) completes equipment deep lubrication, system calibration, parts disassembly inspection, consumable parts replacement, leakage repair;
Equipment supervisor (quarterly/annual overhaul, ledger management) coordinates the annual overhaul plan, third-party calibration of measuring equipment, maintenance ledger audit, extreme working condition maintenance plan adjustment, and fault review.
The complete ledger is the core basis for equipment fault tracing, accessories replacement cycle statistics, and maintenance effect review. The ledger must contain the following information: maintenance date, equipment number, maintenance cycle type (day/week/month/year), inspection items, hidden dangers found, handling measures, number of replacement accessory models, Signed by the operator and signed by the reviewer.
The residual concrete in the main cylinder is thoroughly flushed with high-pressure water, and there is no hardening and clump adhesion to the cylinder wall, stirring arm and blade;
Visually check the degree of wear of the stirring blade and lining plate. If the bolt is not loose and falls off, mark and report immediately if cracks and large-area wear occur;
The two ends of the stirring shaft are sealed to observe whether there is slurry leakage. The oil level of the automatic lubrication pump is sufficient, and there is no oil pipe blockage or oil leakage;
The cylinder of the unloading door opens and closes smoothly, the sealing strip is intact and not damaged, the door is closed without slurry leakage, and the lumpy concrete of the door body is cleaned;
There is no abnormal noise in the operation of the main motor and reducer, no overheating of the fuselage, and no traces of oil seepage or oil leakage in the housing;
The mainframe safety cover is completely fixed, without missing or damaged, and the maintenance entrance cover is locked in place.
The discharge port of the batching warehouse cleans up the lumps of sand and stones. There is no blockage or bridging phenomenon, and the vibrator of the warehouse door is running normally;
There is no large area of adhesive on the surface of the belt, the sweeper adhesive strip fits the belt, and there is no residual aggregate spilling;
Check whether the belt is skewed, torn or layered, and whether the roller and roller rotation are not stuck or abnormal;
The soft connection canvas around the metering bucket is not damaged or leaking, there is no dust on the surface of the sensor, and it can return to zero normally without load;
The protective barriers on both sides of the belt corridor are intact, no one steps on the notch, and the emergency stop rope switch function is normal.
The appearance of the dust collector on the top of the cement and pulvery ash warehouse is intact, there is no damage and ash, and the vibration motor starts and stops normally;
The signal feedback of the material level meter is accurate, the alarm of high material level and low material level is normal, and there is no signal failure;
There is no dust leakage in the shell of the screw conveyor, and there is no abnormal heat and noise in the motor and suspension bearing;
The spiral feed port and discharge port clean up the dust and lumps to avoid blocking the turning card machine.
The liquid level of the clear water tank and the adding agent tank is normal, there is no leakage in the tank, and there is no precipitation lumps at the bottom;
There are no cracks and leakage in the water supply pipeline and the addition pipeline, the valve switch is flexible, and there is no blockage crystallization;
The operation of the addant pump is not idle, the suction is insufficient, and the filter is not blocked;
After daily shutdown in low-temperature environments, empty the pipeline will accumulate water to prevent freezing and cracking of the pipeline and pump body.
The pressure gauge of the air compressor is stable and maintains the standard working pressure of 0.6-0.8MPa;
The gas storage tank manually discharges condensate water every day, and there is no stagnant water in the oil-water separator;
The lubricating oil level of the oil mist is sufficient, and there is no damage to the trachea or leakage of the joint;
The solenoid valve and cylinder respond quickly, and there is no stuttering, air leakage and pressure relief.
The door of the operation control cabinet is closed and sealed, and there is no dust accumulation inside, and there is no aging and exposure of the line;
The test of the emergency stop button, the limit switch of each system and the overload protection device is effective;
The readings of each sensor on the display are stable, there is no abnormal alarm code, and the alarm fault has been handled on the same day;
The cable groove is intact, without crushing or damage, and the grounding line is firmly connected.
There is no abnormal sound in the dust collector fan, and there is no continuous dust leakage in the factory area;
At the end of production, cut off the total power supply, gas source and water source, and hang the equipment maintenance warning sign;
Sort out the on-site materials and tools, record the hidden equipment hazards found on that day, and report them to the equipment supervisor.
Unified lubrication operation of the whole equipment: mixing host shaft end, belt roller, roller, unloading door hinge, vibration motor, spiral suspension bearing are all filled with adaptive grease, and low-temperature special grease is replaced under low-temperature working conditions;
Initial static calibration of the weighing system: use standard weights to calibrate aggregate scales, cement scales, water scales and additive scales one by one, record the weighing error, and adjust the sensor parameters immediately;
The structural bolts of the whole machine are fully tightened: the silo bracket, the mainframe base, the belt rack, and the silo connection bolts are tightened one by one to eliminate the loosening caused by long-term vibration;
In-depth cleaning of the dust removal system: disassemble the dust collector filter bag, blow the dust with compressed air, replace the damaged filter bag directly, and check the sealed cover of the warehouse roof;
Maintenance of vibration equipment: clean up the dust on the shell of the mixing warehouse vibration motor and dust collector, tighten the fixing bolts, and check whether the shock-absorbing spring is broken;
Maintenance of air compressor accessories: replace the air filter, clean up the impurities of the oil-water separator, and check the air compressor cooling fan;
Electrical line fastening and dust removal: open the terminal of the control cabinet, sweep the dust, fasten the loose terminal, and troubleshoot the hidden danger of line aging.
High-precision full set of measurement system calibration: use standard weights for full-range multi-point calibration, retain the calibration data ledger, and repair or directly replace sensors with errors that exceed the standard;
Deep detection of the stirring host: measure the wear gap of the blade and the lining plate, replace the wear thickness if it exceeds 1/2 of the standard thickness, clean up the internal oil sludge of the reducer, and replenish the gear oil as needed;
Internal inspection of the screw conveyor: open the maintenance port to clean up the internal hardening powder, check the wear of the spiral blade and the gap between the lifting bearings;
Hydraulic / reducer oil product detection: take samples to test the oil quality of lubricating oil, and replace all of them immediately if there is blackening, impurities and emulsification;
Anti-corrosion inspection of steel structure: comprehensively check the corrosion points of the silo, frame and belt bracket, polish and remove rust for mild rust, apply anti-rust primer + top paint; check whether the equipment foundation is subsident or cracked;
Special inspection of safety protection facilities: all transmission parts protective covers, high-altitude work guardrails and ladders are fully protected, and if they are missing or damaged, they will be replenished immediately;
Disassemble the head and tail roller of the belt conveyor, clean up the internal accumulated material, check the bearing wear, and replace the aging belt;
Comprehensively check the arch breaking device and fluidized air cushion of the powder silo, clean up the blocked pores, and replace the aging air cushion;
Electrical control system line insulation detection, tidy up messy cables, replace cracked and aging cables;
Complete maintenance of wastewater recovery, sand and stone separation equipment, and clean up the sedimentation tank;
The whole machine is free-load linkage test drive, simulates the fully automatic batching process, tests the PLC automatic control logic, and backs up the control system program;
Fire-fighting facilities are checked. The pressure of the fire extinguisher is in the green range, and the expired fire-fighting equipment is replaced uniformly.
Disassembly and cleaning of the whole machine of the mixing host: thoroughly remove the hardened concrete of the cylinder wall, replace all the worn mixing blades, lining plates and shaft end seals; disassemble the reducer, check the gear meshing wear, and replace the new heavy-duty gear oil;
Batch replacement of consumable parts in the conveying system: unified replacement of aging belts, spiral blades, rollers and roller bearings;
Third-party professional calibration of measuring equipment: entrust a qualified metrology institution to issue calibration reports to ensure metrology compliance;
Comprehensive upgrade and maintenance of electrical system: replace aging cables, contactors, relays, and repair PLC hosts and sensor signal lines
Steel structure flaw detection and reinforcement: weld joints, load-bearing bracket flaw detection, repair welding and reinforcement of severely rusted parts, and re-stratified anti-corrosion coating of the whole set of equipment;
Long-term shutdown and sealing a full set of protection: if the equipment is down for more than 1 month in winter, empty all water tanks, additive pipelines and air compressor gas storage tanks; add anti-rust grease to all lubrication points, and apply anti-rust oil to the exposed metal surface; seal the silo feed port and cut off all external energy.
High altitude and low air pressure, large temperature difference between day and night, low temperature and severe cold in winter, the core risk is pipe freezing and cracking, grease solidification, and insufficient engine power. Replace the lubrication system with NLGI 0-level low-temperature special grease, and add full-point grease replenishment operation once a week; water pipes, adductive pipelines and gas lines are all wrapped in insulation cotton + electric belt, and the water in the pipeline must be completely drained when the work is stopped; the air compressor and reducer are preheated for 30 minutes before starting every day, and the oil temperature reaches Put into production above 20℃; air compressors and diesel power equipment use plateau-specific oil products to shorten the replacement cycle of air filters and prevent insufficient air intake power from decreasing.
In summer, extreme high temperature, large sand and dust, strong ultraviolet radiation, equipment heat dissipation, filter loss, and line aging problems are prominent: motors, reducers, air compressor radiators clean up sand and dust every day, and install auxiliary heat dissipation fans; motor temperature exceeds 90℃, stop and repair immediately; the replacement cycle of air compressor filter elements and dust removal filter bags is shortened to regular 1/2, prevent sand and dust blockage; add a sunshade to the control cabinet and measurement sensor, and wrap the outer layer of the line with anti-ultraviolet protective sleeves; choose high-temperature and anti-aging hydraulic oil and gear oil to detect the oil quality every month to avoid high-temperature failure.
Long-term high humidity and continuous rainfall are prone to powder clumps, electrical short circuits, and steel structure corrosion; rainproof seals are added to the top of the silo, and fluidized air cushions are regularly overhauled to prevent rainwater from seeping into powder and clumping bridges; the control cabinet sealing strips are checked monthly, outdoor sensors are equipped with waterproof protective covers, and the internal moisture of the electric control cabinet is immediately after rain. Gas; Clean up the drainage ditch and sedimentation tank in the factory every day to prevent rain from soaking the foundation of the equipment; check the corrosion point of the rack once a quarter, and clean up the surface water of the equipment in time after rain.
Before carrying out any internal maintenance of the host, belt and spiral, cut off the main power switch of the equipment and pull out the control fuse; hang the switch handle with the warning sign “equipment maintenance, do not close the gate”, and a special person keeps the switch key, and it is strictly forbidden for others to close the gate; the pneumatic system closes the main air valve, emptys the compressed air of the pipeline, and prevents the cylinder accident. The action hurts people.
Before the operation, submit the “Limited Space Safety Operation Ticket”, and the construction can only be carried out after the double approval of the equipment supervisor and the safety officer; open the silo owner’s hole door, the high-power fan is forced to ventilate for 30 minutes, use the gas detector to detect the oxygen content and dust concentration, and enter after meeting the standard; external fixed full-time guardians, the whole process Do not leave the post, and be equipped with lifelines, isolated respirators and emergency rescue equipment.
Operators must wear full-body seat belts, and the hooks must be fixed on a solid load-bearing steel structure; set up a warning area below the high altitude, prohibiting people from passing, and place warning fences; all high-altitude maintenance operations will be stopped in strong wind, rain, frost and slippery weather.
Insulated gloves and insulated shoes must be used for internal maintenance of the electrical control cabinet; the power must be cut off first for line aging and short-circuit failure, and it is forbidden to disassemble the terminal with electricity; reduce the electrical maintenance operation in the rainy season and humid environment, and set up a temporary dry rain shelter if necessary.
Wear dust masks, goggles and wear-resistant gloves when cleaning up dust removal filter bags and powder silos; wear acid- and alkali-resistant rubber gloves when contacting the original liquid of the additizer, and rinse with water immediately after skin contact; turn on the spray dust reduction equipment during the dust operation period in the factory to reduce the hazard of inhalation dust.
| Fault phenomenon | Possible reasons | Prevention and solution measures |
| Abnormal accuracy of ingredients | The weighing sensor is out of stand the humidity changes | Regularly calibrate the weighing system and check the humidity sensor; ensure the stability and uniformity of material flow. |
| The noise of the mixer increases | Wear or loose blades and linings | Check and replace the worn parts; reinforce the connectors and re-lubricate the bearings; ensure cleanliness without debris. |
| The conveyor belt is off. | Insufficient tension, roller wear or poor guidance | Adjust the tension of the belt; replace the wear roller; correct the oriented structure of the conveyor; regularly check the running deviation guide device. |
| The hopper is blocked. | The material door mechanism is stuck, and the material is wet and clumped. | Clean up the residual material in the material door and hopper; check and repair the damaged pneumatic actuator; keep the material dry and unobstructed; use anti-knoting agent regularly. |
| The dust collector is blocked | The filter bag is full or leaking | Clean or replace the filter element regularly; check whether the pulse blowing system is normal; repair the leaking pipe; keep the pressure gauge working normally. |
| Electrical control failure | Loose wiring and aging components | Tighten the terminal blocks and replace the aging relays or cables regularly; check the voltage stability of the power supply; install the surge protection device.
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| Slow operation of pneumatic system | Water retention in the gas storage tank, trachea leakage or blockage | Regularly discharge the water in the gas storage tank; check and replace the aging trachea; keep the filter clean; keep the system refueled and check the pressure gauge. |
Q1: How often should the ready mix concrete plant be maintained?
A1: Daily maintenance (such as cleaning and refueling) should be carried out every day; equipment fastening and parts inspection should be carried out every week; system calibration and parts inspection should be done every month; oil change and comprehensive inspection should be carried out every quarter; and inspection should be carried out at least once a year. The maintenance cycle can be adjusted appropriately according to the on-site load.
Q2: How often should the blender blades be replaced?
A2: The blade replacement cycle depends on the degree of wear and the time of use. It is generally recommended to check the wear condition every 1000~2000 hours during working time, and replace it when the wear limit is exceeded (usually about 30% of the blade thickness is left). For high-intensity operating environments, the replacement cycle can be appropriately shortened.
Q3: How often does the weighing system need to be calibrated?
A3: It is recommended to calibrate aggregate and cement weighing sensors at least once a month; it should be recalibrated immediately when critical projects or abnormal ratios are found. Before calibration, it should be ensured that the scale body is clean and the weighing weight is intact.
Q4: How to reduce the downtime of the mixing plant?
A4: The most effective way is to carry out preventive maintenance and predict faults through regular inspection. Maintain sufficient spare parts inventory, and train skilled operators to carry out front-end inspection, so that measures can be taken in the early stage of failure; at the same time, mobile CMMS and other tools can be used to monitor the equipment status in real time and give early warning.
Q5: How to make an annual maintenance plan for the batching plant?
A5: First of all, refer to the maintenance cycle given in the equipment manufacturer’s manual, and formulate a maintenance periodic table in combination with the actual operating time; then decompose the annual maintenance content into quarterly and monthly inspections; do a good job in the division of labor and time; and reserve sufficient downtime windows for in-depth maintenance and component replacement to avoid affecting the implementation. Work plan.
Practice has proved that after the preventive maintenance of the system, the average trouble-free running time of the equipment can be greatly improved. In the increasingly competitive concrete industry, maintenance is not only a cost expenditure, but also a strategic investment that can bring significant returns. Starting from today, use this list to systematically manage the ready mix concrete plant maintenance, so as to make the equipment more reliable, production more efficient and operation safer.
