Daily pre startup inspection (pre shift maintenance)
1. Mixing host (double horizontal axis/vertical axis planetary)
Check for clumped concrete and debris inside the mixing drum, clean the drum mouth and discharge door for material accumulation;
Check the wear degree of the blades and lining plates, whether the bolts are loose, and tighten them in a timely manner for leakage of slurry and material;
Check the sealing grease cup at the shaft end, add lithium based grease every shift, and prevent leakage and water damage to the bearings;
Whether the unloading door cylinder/oil cylinder and sealing strip are damaged, whether the switch is smooth, and whether there is any leakage of slurry;
The oil level observation window of the reducer maintains the oil level between the upper and lower scales without oil leakage or abnormal noise.
2. Batching machine (aggregate bin, belt, material door)
Check for material jamming or rust on the doors and vibrators of each aggregate bin, and replace the seals promptly if there is any air leakage in the cylinder of the material door;
Flat belt/inclined belt: clean the adhesive material on the drum and idler, check for belt deviation, tearing, and fuzzing;
Replace the belt cleaner and material blocking skin in a timely manner to prevent the scattering of aggregates;
Add lubricating grease to the drum and roller bearings, and listen for any abnormal noise when idling.
3. Powder system (cement silo, fly ash silo, screw conveyor)
Is the cement silo level gauge and high/low level alarm working properly;
Warehouse top dust collector: Clean the filter element dust, check the vibration motor to prevent blockage and dust emission in the warehouse;
The arch breaking device (air disc/vibrator) has smooth ventilation and no blockage, avoiding the arching of powder materials and preventing them from not being discharged;
Spiral conveyor: observe whether there is any abnormal noise or powder leakage during operation, and lubricate the bearings at both ends daily;
Butterfly valves and pneumatic valves have good sealing, flexible opening and closing, and no air leakage from the gas source.
4. Water and admixture supply system
Are there any leaks in the water pump and admixture pump, and are there no blockages in the pipelines;
Zero point calibration of water meters and additive measuring scales, daily cleaning of pipeline filters and screens;
The mixing motor of the admixture tank is turned on at regular intervals to prevent the stratification and sedimentation of the admixture;
Drain the pipeline of accumulated water in winter to prevent freezing and cracking.
5. Measurement system (core maintenance, affecting proportioning accuracy)
Clean the hopper of the aggregate scale, cement scale, water scale, and admixture scale to ensure that there is no accumulated material or load during weighing;
Check the connection wire and limit block of the weighing sensor for any collision or jamming;
Before class, the empty scale returns to zero, and if zero drift is found, it should be calibrated in a timely manner;
The soft connection canvas of the weighing bucket is free of damage and material leakage.
6. Pneumatic and hydraulic systems
Air compressor: Check the pressure and oil level of the air storage tank, and drain the condensed water at the bottom of the air storage tank;
Drain the oil-water separator, clean the filter element, and ensure that the compressed air is dry and free of oil and water;
Hydraulic station oil level, oil temperature, and oil pipe joints have no leakage, and the filter element is regularly inspected;
Add lubricating grease to all cylinder grease fittings.
7. Electrical and Control Systems
Close the doors of the control room and distribution box to prevent dust and water damage, and clean the dust on the cooling fan;
Emergency stop button, limit switch, and sound and light alarm function testing;
The motor cables are free from damage or aging, and the grounding protection is reliable;
The computer and sensor circuit connectors are securely fastened and free from moisture and oxidation.
Post shift shutdown cleaning (daily mandatory)
Host cleaning: Mix water and stones in idle for 3-5 minutes, wash away residual concrete on the cylinder wall and blades, and discharge sewage; It is strictly prohibited to clean dry and hard lumps the next day;
Wash the scattered sand and gravel from the discharge hopper, belt conveyor, and batching machine to avoid solidification and agglomeration;
Clean the sticky mortar in each weighing hopper to prevent long-term adhesion and inaccurate weighing;
Clean up the dust and waste accumulated on the entire machine platform and aisle, and keep the equipment clean;
Drain the air compressor and storage tank, turn off the main air source and power supply;
Circulating flushing of additive pipelines to prevent crystallization blockage.
Regular weekly maintenance
Apply lubricating grease uniformly to all lubrication points (bearings, shaft ends, rollers, cylinder pin shafts);
Check all connecting bolts: the main engine, batching machine, cement silo, and bracket foundation bolts are fully tightened;
Adjust belt tension, repair damaged belts, and replace faulty cleaners;
Clean all filter elements of the dust collector on the top of the warehouse and inspect the vibration mechanism;
Overall calibration of the measuring system, checking the weighing errors of each scale;
Check the gearbox and hydraulic oil for emulsification and blackening, replace the filter element for minor impurities;
Check the wear and breakage of the steel wire rope and lifting hopper (bucket type), lubricate the steel wire rope;
Check for leaks in valve and cylinder seals, and replace damaged parts due to air leakage.
Monthly in-depth maintenance
Sampling and testing of reducers and hydraulic oil. If there is severe pollution, replace the oil directly and clean the oil tank;
Open the maintenance door of the mixing host, comprehensively inspect the wear of the lining plate, mixing arm, and blades, and replace them in a timely manner if the wear exceeds one-third;
Disassemble the bearings at both ends of the screw conveyor for inspection and clean the internal clumped powder;
Replace the air filter and oil filter of the air compressor, and replace the oil of the air compressor as needed;
Moisture proof treatment of sensors and junction boxes, and fastening of all wiring terminals;
Check the walls of the cement and powder silos for any clumping, and manually clear them if necessary;
Rust removal and repainting of the entire machine, checking for cracks and deformations in the welds of the support legs and brackets;
Calibration of safety valves and pressure gauges to ensure the sensitivity and effectiveness of safety devices.
Quarterly/Annual Overhaul and Maintenance
Replace all gearboxes with specialized gear oil and clean the casing;
Replace the entire set of shaft end seals of the mixing host and thoroughly clean the mortar on the shaft head;
The belt conveyor drum and idler are severely worn and need to be replaced directly;
Fully verify all measuring equipment and issue weighing calibration records;
Overall maintenance of electrical system circuits, replacement of aging cables, contactors, and relays;
Safety inspection of gas storage tanks and pressure pipelines;
Rust removal, anti-corrosion, and repainting of the entire equipment.
Key points for special maintenance of key components
1. Sealing of mixing host shaft end (vulnerable core)
It is strictly prohibited to lack butter, as it can quickly enter the slurry and damage the bearings;
If there is a slight leakage, immediately add lubricating grease. If there is a serious leakage, stop the machine and replace the seal;
When flushing the equipment, avoid direct flushing of high-pressure water onto the shaft end position.
2. Maintenance of measuring scales
Heavy objects are prohibited from hitting the weighing hopper, and materials are not allowed to be stacked on the hopper;
Wipe the sensor dry in a timely manner on rainy days and cover it with rain protection;
Perform zero point reset before mass production and third-party calibration every quarter.
3. Dust collector
Filter blockage can cause slow powder discharge and ash emission from the top of the warehouse;
Increase the frequency of drainage on rainy days to prevent the filter element from getting damp and sticking.
4. Air compressor
Drain water daily, clean the filter element weekly, and change the engine oil on time;
The pressure should be maintained at 0.6-0.8MPa. Insufficient pressure can cause the cylinder to move weakly and the discharge door to not close tightly.
Usage taboos and maintenance precautions
Prohibit large stones and steel bars from entering the main engine to avoid damaging the blade lining plate;
Do not open the maintenance door or reach into the mixing drum during equipment operation;
Long term overload operation is strictly prohibited to prevent damage to motors and reducers caused by overload;
Keep water tanks, additive tanks, and pipelines insulated and antifreeze in winter;
During the rainy season, ensure that electrical cabinets and sensors are well protected against rain and water;
Establish a maintenance ledger to record daily lubrication, calibration, and parts replacement times;
Pre stock vulnerable parts (liners, blades, seals, belts, filters, rubber strips) to reduce downtime.
