To improve the efficiency and quality of concrete mixing plant, it is essential to understand the common troubleshooting and daily maintenance of concrete mixing plant machinery. Take HZS180 concrete mixing plant as an example, there are many things to pay attention to.
Common faults and troubleshooting methods
- Mixing system common troubleshooting
The mixing system of the concrete mixing plant mainly consists of the mixing transmission unit and the mixing unit. During operation, the following problems may occur in the mixing host.
(1) The gap between the mixing blades and cylinder wall is too large, the mainframe residual concrete is too much, the liner plate and blades have damage phenomenon, these problems will lead to the mainframe residual concrete amount exceeds the standard.
Elimination method: need to adjust the distance between the mixing blade and the cylinder wall, the damage to the blade and liner leaf timely replacement.
(2) Mixing machinery discharge slurry leakage, in the operation process, the discharge door is not completely closed, the damage of the liner plate causes the mixer discharge door slurry leakage.
Elimination method: Before the relevant concrete machine and equipment start to run, the relevant personnel should carry out strict inspection, timely swap the liner, to avoid the discharge door and cylinder gap.
(3) Mixer shaft end seal damage, in the operation process is not regularly injected into the lubricant, resulting in slurry squeeze in, seal damage phenomenon.
Elimination method: Mixer shaft end seal should be carefully cleaned, the damaged parts should be replaced in time. Before injecting lubricating oil, should squeeze out the mud and dirt oil outside the cavity.
- Other common troubleshooting
Water, admixture supply system
- No water or admixture from the pump
If the pump is not full of liquid and air flows in the pump chamber, it is easy to cause clogging of the pump body and failure of the bottom valve to open, resulting in serious failure of the pump to deliver water or additive.
- Elimination method: Fill the pump with water to ensure that there is no air in the pump, and then carefully check the bottom valve to remove the blockage.
Reduced pump flow
This problem mainly occurs because the valve opening is not enough or the pump vane wheel part of the windings are more.
Remedy: Remove the blockage in the pipeline and on the impeller blade, adjust the valve switch appropriately and increase the pump speed.
(3) Pump leakage or leakage of additives
When the seal is excessively worn, the pump body will crack or sand holes will appear, in addition, if there is a problem in the installation process or the installation screws are loose can cause such problems.
Remedy: Replace the seal ring in time and pay attention to details during installation, especially the loose screws.
- Air supply failure
If the pressure of the air line system rises slowly or the pressure cannot be adjusted up, it is easy to cause the pneumatic components to have insufficient power and cannot be turned off or opened.
Elimination method: to replace some old parts in time, update the regulator spring, and then clean.
(2) The failure of the oil-water separation as well as the oil mist failure will cause the failure of the compressed air handling components.
Elimination method: clean the filter element, mainly clean the oil and impurities in the drainer, update the regulator spring, and clean it afterwards. Then perform a detailed check of the air flow to the inlet to see if there are any air leaks. Adjust the oil volume to avoid blockage phenomenon, at the same time, timely exclude the water deposited at the bottom of the water cup, and timely replace the seal ring.
- Pneumatic actuators problems mainly due to improper cylinder assembly or long-term use, pneumatic actuators will occur inside and outside the leakage problem, but also the lack of output force, buffer effect is not good, cylinder cover damage and other phenomena.
- Elimination method: in machinery and equipment in the course of operation, if the cylinder leaks inside and outside the problem, the piston rod should be properly adjusted to ensure that the distance between the piston rod and cylinder barrel, regular inspection of the oil mist work, timely replacement of worn seals and sealing rings.
- When the cylinder output force is insufficient or unstable action, adjust the piston rod in a timely manner, check whether the air supply pipe is blocked. If the cushioning effect of the cylinder is not good, replace the seal ring and adjust the damaged screw. If the cylinder piston rod or cylinder cover problems, to adjust the piston rod and screws, the sealing ring for technical cushioning.
Daily maintenance of concrete mixing plant
01 Mixer and batching system
Transmission system, equipment in the operation process, should be in accordance with the provisions of the transmission gear, reducer and chain and other lubricants to add enough, and at the same time to carry out a detailed inspection of the equipment, to avoid problems in the operation process, affecting the efficiency. If there is bearing oil leakage, heat, brake pad wear phenomenon, should be replaced in a timely manner.
To ensure long-term stable operation of the oil seal structure, the bearing end seal should be regularly refueled. As for the mixing system, to ensure the normal operation of the mechanical equipment, it should be ensured that the mixer runs smoothly and the blades and other components are not loose. If the blades and mixing arms show wear, they should be replaced in time, and the residual concrete in the equipment should be cleaned up in time.
02 Water and admixture pathways
The flow of water can be affected by many factors, especially the sealing of the pump, and if a clean water source is not used during the operation of the machinery, it will not only affect the metering, but also cause blockages in the waterways. The accuracy of water metering can be affected by the pump installation and seal installation. Water pump seals should be inspected and repaired in time if problems occur during normal operation to avoid affecting the construction, and relevant records should be kept.
03 Maintenance and repair of the air line
For air compressors, it is important to ensure that the oil level is on the lowest line during operation, and the relevant personnel should regularly check the oil level and the quality of the lubricant, and should replace and add it according to the actual situation. It should also be noted that 19 compressor oil should be used in summer and 13 compressor oil in winter. The compressor should be placed in a flat and clean place, and the working environment should not be damp and dusty. As for the oil and water of the gas cylinder, it should be drained every two shifts to ensure the sensitivity of the safety valve, and checked regularly, about once every 3 months, the silencer needs to be cleaned every 250h.
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