1. Common faults and solutions of concrete mixing station equipment
During the use of concrete mixing station equipment, due to the aging, wear and environmental impact of parts and other reasons, faults often occur. Various faults, common faults and solutions are as follows:
1. The main motor of the mixer cannot be started
Fault phenomenon: Press the mixer on the operating table Press the start button and the blender will not start.
Cause analysis:
(1) The air compressor did not start or the air supply system pressure did not reach 0.4MPa.
(2) The maintenance protection switch of the mixing host and the keyed emergency stop switch on the host are not turned on.
(3) The emergency stop switch on the operating table has not been reset.
(4) The host power switch is not turned on.
(5) The host stop signal must be reset.
Processing method:
(1) Check whether the compressed air detection signal (air pressure signal greater than 0.4MPa) is sent to the PLC, that is, whether there is a signal at I8.0. If there is no signal from I8.0, check whether the air compressor pressure is greater than 0.4MPa. When the pressure reaches above 0.4MPa and there is no signal from I8.0, check whether the adjustment of the electric contact pressure gauge is normal or damaged until I8.0 is Signal.
(2) Check whether the signal on the maintenance protection switch of the mixing host is sent to the PLC, that is, whether there is a signal in I9.7.
(3) Check whether the emergency stop switch on the operating table is reset and whether there is a signal from I0.1.
(4) Check whether the host power switch is turned on and whether there is a signal on I3.4.
(5) Check whether the host stop button is reset and whether I5.2 is connected.
2. In the automatic production process, the batching machine does not discharge the aggregate after weighing it.
Fault phenomenon: In the automatic production process, a Or a variety of aggregates are weighed in the weighing hopper and are not discharged, and the system stops running.
Cause analysis:
(1) The hopper is not closed properly.
(2) The weighing instrument has no discharge output signal.
(3) The belt conveyor does not start.
(4) The precision weighing door of the aggregate scale is not closed in place.
(5) The unloading sequence of aggregates must be defined.
Processing process:
(1) Check whether the material is stuck in the hopper valve or the door is not closed properly. After the door is closed in place, there is a signal from I6.7.
(2) Check the aggregate weighing instrumentWhether to output signal for unloading, stone 1 unloading I0.4, stone 2 unloading I0.7, sand 1 unloading I1.5, sand 2 unloading I1.2.
(3) Check whether the belt conveyor is started.
(4) Check whether the fine weighing door of the aggregate is closed in place. Stone 1 is finely weighed and the door is closed at I8.2. Stone 2 is finely weighed and the door is closed at I8.3. Sand 1 is finely weighed and the door is closed at I8.5. Sand 2 is finely weighed and closed. Precisely called closing the door I8.4.
(5) Check the computer interface to see if the aggregate unloading sequence is defined.
3. The inclined belt does not start.
Fault phenomenon: After the mixer starts normally, press the inclined belt start button on the operating table, and the inclined belt does not start. .
Cause analysis:
(1) The mixer does not start.
(2) The inclined belt maintenance stop switch has not been reset.
(3) The power switch of the inclined belt conveyor is not turned on.
(4) The stop button switch of the inclined belt conveyor has not been reset.
(5) The washing button is not reset.
Processing process:
(1) Check whether the inclined belt maintenance stop switch is reset and I7.7 is turned on.
(2) Check whether the power switch of the inclined belt conveyor is turned on and I7.6 is turned on.
(3) Check whether the stop button switch of the inclined belt conveyor is reset and I11.4 is connected.
(4) Check whether the washing button is reset and I5.3 is disconnected.
4. The aggregate weighing hopper does not feed material
Fault phenomenon: In the automatic state, press cycle start or single disk start, one or Several aggregates are not weighed.
Cause analysis:
In the automatic state, the process of aggregate weighing is as follows: PLC gives a weighing signal to the instrument, and the weighing instrument outputs the rough weighing sum according to the formula setting value. The precise weighing signal is sent to the PLC. After the PLC receives the coarse weighing and fine weighing signals, when the discharge door of the aggregate weighing hopper is closed, it outputs a signal to the solenoid valve of the coarse weighing and fine weighing feeding door. The solenoid valve gets After the signal, the fine and coarse weighing feed doors are opened and the weighing starts. When the weight of the aggregate scale reaches the precise weighing requirements, the coarse weighing signal of the instrument stops outputting, the coarse weighing solenoid valve is powered off, and the coarse weighing door is closed. When the weight of the aggregate scale reaches the drop value, the precision weighing signal of the instrument stops outputting, the precision weighing solenoid valve is powered off, the precision weighing door is closed, and the weighing is completed. It can be seen from the production process that the factors that affect weighing include: whether the weighing instrument gives a weighing signal to the PLC, whether the PLC gives a signal to the solenoid valve, whether the solenoid valve can reverse normally, etc.
Processing process:
(1) Check the closing position of the weighing hopper discharge door, the 1# stone weighing hopper closing position signal I5.5, the 2# stone weighing The signal of bucket closing is in place I5.6, the signal of 1# sand weighing bucket closing in place is I6.0, the signal of 2# sand weighing bucket closing is in place I5.7.
(2) Check the weighing signal output by the instrument, stone 1 rough weighing signalNo. I0.5, stone 1 precise weighing signal I0.6, stone 2 coarse weighing signal I1.0, stone 2 precise weighing signal I1.1, sand 1 coarse weighing signal I1.6, sand 1 precise weighing signal I1.7, The coarse weighing signal of sand 2 is I1.3, and the precise weighing signal of sand 2 is I1.4.
(3) Check the output signal of the PLC. The feed signal of stone 1 is Q0.1, the feed signal of stone 2 is rough weighing Q0.2, the feed signal of stone 2 is fine Q0.3, and the feed signal of stone 2 is Q0.3. The feeding signal of coarse weighing 1 is Q0.6, the feeding signal of fine weighing of sand 1 is Q0.7, the feeding signal of coarse weighing of sand 2 is Q0.4, and the feeding signal of fine weighing of sand 2 is Q0.5.
(4) When there is a signal output to the solenoid valve but no material is fed, check whether the solenoid valve coil is burned out or whether the valve core is stuck.
5. Powder feeding is slow
Fault phenomenon: The screw machine feeds very slowly, and the feeding time exceeds 2 minutes, while normal feeding is less than 20 seconds. .
Cause analysis:
The main influencing factors are poor loading of the powder tank and damage to the screw conveyor. The manifestations of poor powder feeding include arching of the powder, agglomeration of material at the outlet of the powder tank, too small opening of the discharge butterfly valve, insufficient material in the powder tank, etc. The damage to the screw conveyor is mainly due to the deformation of the spiral blades and the inability to convey normally.
Processing process:
(1) Turn on the air blowing arch breaking device.
(2) Check the opening of the powder tank discharge butterfly valve and keep the butterfly valve in the fully open position.
(3) Check whether the material at the outlet of the powder tank is agglomerated.
(4) Check whether the screw machine blades are deformed. If they are deformed, remove them, correct them or replace them.
6. Belt deviation
Fault phenomenon: When the belt conveyor is running without load or with load, it deviations to one side or for a while. The phenomenon of running on the left side for a while and then running on the right side will cause material leakage, abnormal wear and damage of equipment, reduce productivity, and affect the normal operation of the entire equipment.
Cause analysis:
The result of the external force on the tape in the width direction of the tape is not zero or the tensile stress perpendicular to the width direction of the tape is uneven. Since there are many factors that lead to tape deviation, the deviation of the tape should be solved from the aspects of conveyor design, manufacturing, installation and commissioning, use and maintenance, such as the tightness of the two sides of the tape is different, the height of the two sides of the tape is different, etc. Similarly, if the roller bracket and other devices are not installed in the vertical section of the belt running direction, it will cause the belt to deviate.
Processing process:
(1) Adjust the tensioning mechanism method
When the tape is running, if the tape moves to the same side under no-load and heavy-load conditions, If the tape deviates, it means that the tightness on both sides of the tape is different, and it can be adjusted; if the tape deviates from left to right and has no fixed direction, it means that the tape is loose, and the tensioning mechanism should be adjusted.
(2) Adjusting the roller method
If the tape deviates at the roller, it means that the installation of the roller is incorrect.The installation is not level enough, the drum moves axially, or one end of the drum is in front and the other is behind. At this time, the levelness and parallelism of the drum should be corrected.
(3) Adjusting the roller bracket (or frame) method
If the tape always deviates to one side when no-load, the roller bracket on the deviation side should be Move forward 1-2cm in the direction of tape running (see Figure B), or increase the height of the roller bracket (or frame) on the other side appropriately.
(4) Sticky removal method
If there is material stuck to part of the roller or roller, the diameter of that part will increase, causing the tape tension there to increase. This results in deviation. Adhering materials should be cleaned up in time.
(5) Adjust gravity method
If the tape does not deviate when it is unloaded, but always deviates to one side when it is heavily loaded, it means that the tape has been deviated. The position of the hopper or tape conveyor should be adjusted so that the tape is evenly loaded to prevent deviation.
(6) Tape adjustment method
If the edges of the tape are severely worn or the tape seams are not parallel, the tension on both sides of the tape will be inconsistent. The tape should be retrimmed or replaced.
(7) Method of installing offset rollers
If several sets of automatic self-aligning rollers (flat rollers or grooved rollers) are installed on the conveyor, the belt running can be automatically corrected. partial phenomenon. For example: when the tape runs off track and rubs against the small roller on one side, the bracket on that side should move forward along the running direction of the tape, and the other side should move backward relatively. At this time, the tape will move backward. The retaining roller moves on one side until it returns to its normal position.
(8) Installing the limit roller method
If the tape always deviates to one side, a limit roller can be installed on the frame on the deviation side; in this way, a On the one hand, it can force the tape to reset, on the other hand, the vertical roller can reduce the tension of the tape on the side of the deviation and make the tape move to the other side.
7. Mixer tripping
Fault phenomenon: During the feeding and mixing process, the mixing host tripped due to excessive current.
Cause analysis:
The result of the external force on the tape in the width direction of the tape is not zero or the tensile stress perpendicular to the width direction of the tape is uneven. Since there are many factors that lead to tape deviation, the deviation of the tape should be solved from the aspects of conveyor design, manufacturing, installation and commissioning, use and maintenance, such as the tightness of the two sides of the tape is different, the height of the two sides of the tape is different, etc. Similarly, if the roller bracket and other devices are not installed in the vertical section of the belt running direction, it will cause the belt to deviate.
(1) Too much material is fed, causing the mixer to be overloaded.
(2) The gap between the blades and the lining plate of the mixing system is too large, which increases the resistance during the mixing process.
(3) The triangle transmission belt is too loose, making the transmission system inefficient.
(4) The safety inspection switch on the upper cover of the mixing host was loosened, causing the machine to shut down.
Processing process:
(1) Check whether the batching system exceeds the standard and whetherThere is a phenomenon of secondary feeding.
(2) Check whether the gap between the mixer blade and the liner is 3~8mm.
(3) Check the tightness of the V-belt of the transmission system and adjust it. Check whether the safety switch on the upper cover of the main unit is loose.
8. There is no signal when the mixer discharge door is closed
Fault phenomenon: After the mixer has finished unloading the material, the unloading door is closed, but there is no door signal. Cause the program to stop running.
Cause analysis:
The signal must be sensed only if the distance between the mixer discharge door proximity switch and the rotating handle pointer on the discharge door does not exceed 5mm. When the discharge door does not meet the requirements due to the pressure of the oil pump or the discharge door is stuck by the residual material in the mixer when it is closed, the proximity switch cannot approach the rotating handle pointer and there is no signal. Because the proximity switch or the rotating handle pointer is loose, the proximity switch or the rotating handle pointer is loose. When the distance exceeds 5mm, the proximity switch cannot sense the signal. If the proximity switch is damaged, there will be no signal output.
Processing process:
(1) Check whether the working pressure of the hydraulic system of the discharge door reaches the requirement (13MPa)..
(2) Switch to manual, Open the mixer discharge door, let the stuck residual material fall out, and then close it.
(3) Check whether the proximity switch and the handle pointer are loose.
(4) Check whether the proximity switch is damaged.
9. Uneven concrete mixing
Fault phenomenon: The concrete discharged by the mixer is uneven, dry on one side and wet on the other.
Cause analysis:
If the mixing time is too short, the mixing will be uneven. In addition, if the nozzle of the mixer’s water pipe is installed incorrectly, the water spray will be uneven, making it easier for the concrete to dry on one side and on the other. wet.
Processing process:
(1) Check whether the stirring time is too short (usually 30 seconds). If the stirring time is too short, the stirring time can be extended.
(2) Check whether the installation order of the nozzles of the water spray pipe is correct. The correct order is that the nozzles on the side of the drainage pump are the smallest, the nozzles on the other side are the largest, and the nozzles in the middle are evenly arranged in order from small to large. .
10. Inaccurate weighing of aggregates
Fault phenomenon:
(1) Aggregate is always weighed too much .
(2) Aggregate is always weighed too little.
(3) The aggregates are weighed for a while and then become less.
Cause analysis:
The aggregate weighing error is closely related to the fine setting, drop and discharge uniformity. The fine setting data must be greater than the drop, otherwise, the fine setting signal has not been output yet, the drop signal has been sent, and the unloading will stop.
Processing process:
(1) There is always too much aggregate, which can be solved by adjusting the large gap. After the drop is increased, it is necessary to check whether the value is smaller than the fine setting value. If the drop is greater than the fine setting, the fine setting value should be increased accordingly.
(2) There is always too much aggregate, which can be solved by adjusting the small gap. After the height difference is reduced, the fine setting value generally does not need to be adjusted.
(3) The aggregate is weighed for a while and becomes more and less. First check the uniformity of the discharge, check whether there is any debris stuck in the discharge port, etc., and then adjust the fine setting and gap.
11. Inaccurate weighing of powders
Troubleshooting:
(1) Powders are always weighed too much .
(2) The powder is always weighed too little.
(3) Weigh the powder for a while and then it will be more and then less.
Cause analysis:
The factors related to powder weighing include the setting of the height difference, the feeding uniformity of the screw machine, the influence of the negative pressure of the dust removal in the main building, etc.
Processing process:
Always too long or always too small can be corrected by adjusting the gap. When the weighing is unstable, the uniformity of feeding by the screw machine should be checked (mainly to see whether the powder tank is unloading smoothly) and dealt with. Also check whether the dust removal pipeline in the main building and the filter element of the dust removal machine are blocked.
12. Inaccurate weighing of admixtures
Fault phenomenon:
(1) The admixtures are always weighed too much .
(2) The weighing of admixtures is always too low.
(3) Weigh the admixture for a while and then add less.
Cause analysis:
Mainly due to the impact of the drop and the opening of the manual ball valve.
Processing process:
Adjust the drop first. If there are still problems with weighing after adjusting the drop, close the manual ball valve in the admixture pipeline and then adjust the drop.
13. After the powder scale measures accurately, the reading of the weighing instrument gradually becomes smaller
Fault phenomenon: During the automatic production process, the powder metering hopper The materials gradually become smaller after being weighed.
Cause analysis:
It is mainly caused by the unloading pneumatic butterfly valve not closing tightly. The factors that cause the pneumatic butterfly valve to not close tightly include: improper position of the limit screw when assembling the pneumatic butterfly valve, causing the butterfly valve itself to not close in place, and material sticking to the outlet of the butterfly valve, which will also cause the pneumatic butterfly valve to not close in place.
Processing process:
(1) First disassemble the red hose connected to the pneumatic butterfly valve and check whether there is any material stuck to the butterfly valve. If so, when the butterfly valve is open , use a steel brush to clean away the material.
(2) Check whether the position of the limiting jackscrew of the butterfly valve is appropriate. You can limit the opening of the butterfly valve by adjusting the jackscrew.
14. The ratio cannot be downloaded to the instrument or the instrument display data cannot be uploaded to the computer or the instrument does not start up
Fault phenomenon: After the task is set, use Click the mouse to save and download, but the weighing instrument cannot accept the data downloaded from the computer. During the production process, the weight data detected by the weighing instrument cannot be transmitted to the computer.The corresponding data control window on the computer interface does not respond.
Cause analysis:
The weighing instrument and the computer are connected through a one-to-eight serial port line. If the communication line between the instrument and the computer is loose, disconnected, short-circuited or damaged, there will be no communication between the instrument and the computer. In addition, incorrect parameter settings of the instrument may also affect communication.
Processing process:
Check whether the communication line connector is defective and deal with it, and check whether the instrument parameter settings are correct.
15. Digital drift of the weighing instrument when it is static
Fault phenomenon: In the natural state, the instrument display data changes continuously.
Cause analysis:
The weight data displayed by the weighing instrument comes from the current signal transmitted from the sensor junction box. If the instrument shows a large weight fluctuation, it means that the current signal transmitted from the sensor junction box fluctuates. . Damage to the sensor’s internal bridge or loose connections in the sensor junction box will cause current fluctuations.
Process:
Remove all the wiring of a certain sensor on the junction box and see if the instrument data continues to drift. If the instrument data stops drifting, it can be determined that the sensor wiring is loose or the sensor is damaged. Reconnect all the wiring of the removed sensor to the junction box. If the instrument data stops drifting, it means that the cause is loose wiring. If the instrument data continues to drift, the sensor is damaged, which can be solved by replacing the sensor. If the instrument data continues to drift after removing a certain sensor, remove the other sensor (do not connect the wiring of the removed sensor yet) and handle it in a similar way.
16. After the hopper is unloaded, the material indicator light continues to flash.
Fault phenomenon: After the hopper is unloaded, the bucket valve is closed, and the material indicator light continues to flash. Continue to flash.
Cause analysis:
When the hopper is unloading, the indicator light in the hopper starts to flash. When the unloading is completed, the valve of the hopper is closed and the closing signal is in place (I6.7) , wait until the hopper filled indicator light stops flashing. If the bucket valve is closed and the material indicator light continues to flash, it can be judged that the bucket valve is not closed in place or the door is closed in place. The installation position of the travel switch or magnetic switch is loose. This fault will also occur if the proximity switch or magnetic switch is damaged.
Processing process:
Check the closing condition of the valve of the hopper to be hopper. If it is stuck and not closed due to aggregate or other reasons, switch to manual state and press to discharge the hopper. button to open the bucket valve to make the aggregate stuck on the bucket valve fall down, then release the hopper unloading button to close the bucket valve in place, and then switch to the automatic state. You can also use the mouse to click on the hopper unloading control on the computer monitoring interface in the automatic state, open the hopper valve, clear the material and then close it.
If the travel switch or the magnetic switch on the cylinder is loose, especially the magnetic switch, adjust the switch position and tighten it. If the door is closed in place and the switch position is normal, you need to check whether the travel switch or magnetic switch isis damaged.
17. When the overlay weighing screw conveyor is switched, its circuit breaker trips.
Fault phenomenon: After the fly ash weighing is completed, it switches to the mine. The powder spiral trips when it starts.
Cause analysis:
Because the two spiral conveyors share an air switch, when the fly ash spiral is powered off, its contactors are not immediately disconnected. Starting the mineral powder screw machine again can easily cause a short circuit.
Processing process:
Prolong the conversion time by adjusting F6.3.3.2 on the T600.02 instrument.
18. The mixer does not unload after the mixing time is up
Fault phenomenon: During the automatic production process, after the mixing time becomes zero, the mixer does not unload material.
Cause analysis:
Under normal circumstances, after the mixing time becomes zero, the mixer will automatically unload, but during the production process, the pause button on the console was pressed or the If the mouse clicks on the discharging control on the computer monitoring interface, the mixer will not unload after the mixing time is up. In addition, the solenoid valve of the discharge door is damaged, the discharge door cannot be opened, and the mixer will not discharge.
Processing process:
(1) Check whether the pause button on the operating table is pressed. If pressed, reset.
(2) Check whether the discharging prohibition control on the computer monitoring interface is activated. If activated, cancel it.
(3) Check whether the discharge solenoid valve is working properly.
19. When one solenoid valve operates, all solenoid valves are energized
Fault phenomenon: During the automatic production process, all pneumatic doors of the batching station are open .
Cause analysis:
(1) Line 100 on the printed circuit board is not connected or has poor contact.
(2) The freewheeling diode on the printed circuit board breaks down.
Processing process:
(1) Check the No. 100 line on the printed circuit board and connect it properly.
(2) Replace the entire printed circuit board or only the damaged freewheeling diode.
20. The host computer system prompts that the encryption lock is not detected or the encryption lock initialization error
Fault phenomenon: After the computer is started, an alarm prompts that the encryption is not detected. Lock or dongle initialization error.
Cause analysis:
The concrete mixing control system is developed on the configuration software. When using the configuration software, the encryption lock must be correctly installed on the computer and the encryption lock driver must be installed. program. When the encryption lock is not installed properly or is damaged, the computer cannot detect it. The cause of the dongle initialization error is a problem with the driver.
Processing process:
(1) Shut down the computer, pull out the encryption lock, check it and then reinstall it. If it has been checked multiple times, check again.If the encryption lock cannot be detected, the encryption lock or computer motherboard needs to be replaced.
(2) Reinstall the driver.
21. Unable to enter the operating system
Fault phenomenon: When starting the computer, you are prompted to insert the system startup floppy disk
Cause analysis:
p>
System files are lost due to hardware or software reasons.
Processing process:
(1) Use the system disk to restore.
(2) Re-clone the hard drive and replace it.
22. The powder tank material level gauge indicates abnormally
Fault phenomenon: There is material in the powder tank, but there is no material in it, and the material level gauge shows that there is material.
Cause analysis:
When the powder in the powder tank covers the material level meter, the rotating blade of the material level meter encounters resistance and stops rotating. At this time, the material level meter gives a material signal. When there is too much material sticking to the rotating blade of the material level machine to a certain extent or the gap between the rotating blade and the mounting base is too small and gets stuck, the material level meter cannot rotate and the material level meter will output a material signal. In addition, incorrect wiring of the material level meter or damage to the material level meter will also send out an error signal.
Processing process:
(1) Remove the material level gauge and clean the powder standing on the rotating blade.
(2) Check whether the gap between the rotating blade and the mounting seat cover is sufficient. If it is too small, it needs to be dealt with.
(3) Check whether the wiring of the material level meter is correct.
(4) Dismantle the power-on test to determine whether the material level meter is damaged.
23. The production screen does not start and the feeding animation is displayed.
Fault phenomenon: Production is not started and the computer monitoring screen displays the feeding animation.
Cause analysis:
The feeding animation of the computer monitoring screen is related to the closing position signal of each pneumatic door. The door closing signal is transmitted to the computer through the PLC.
Processing process:
Check whether the PC/PPI communication cable connection between the PLC and the computer is correct and reliable.
24. A certain material does not feed automatically or manually, but it can be fed when operating the upper computer
Fault phenomenon: In automatic or manual state, There is no response when pressing the feed button on the operating table, but clicking the feed button on the computer monitoring interface with the mouse can feed.
Cause analysis:
The most basic condition for measuring each material is that the discharging door of the weighing hopper must be closed in place, and the closing door signal is input to the PLC, but the input on the computer interface The feed button can skip this condition and force feeding.
Processing process:
Check whether the door closing signal for this type of material is in place.
25. Screw conveyor tripped
Fault phenomenon: The screw conveyor motor can start but then immediatelyJust stop
Cause analysis:
(1) The power supply voltage is too low or the air switch adjustment current is too low.
(2) There is foreign matter stuck in the powder.
(3) The rotation direction of the screw machine is reversed.
(4) The screw machine is deformed during installation.
Processing process:
(1) Check whether the power supply and air switch adjustment current meet the requirements.
(2) Clean and check the screw machine for foreign matter.
(4) Check the straightness of the screw machine.
26. The aggregate feed door is stuck
Fault phenomenon: The pneumatic door for the gravel feed in the batching station is stuck by stones and cannot be opened.
Cause analysis:
The pneumatic door of the batching station has a large gap door and a small gap door. The gap of the large gap door is larger than the average stone particle size, so there will be no jamming. The gap of small gap doors is generally 5~10mm. When stones below 10mm get stuck in the gap, it will be difficult to jam the pneumatic door. After the batching station has been used for a period of time, the aggregate outlet is worn. When the gap is worn to 20~30mm, larger stones are stuck into the gap. During the process of opening the door, the stones are easily stuck (shaped force) , so that the pneumatic door cannot be opened.
Processing process:
Check the pneumatic door gap and adjust it to the appropriate value. If it cannot be adjusted to the appropriate value due to excessive wear, you need to add a welded steel plate or round steel to the material opening. , so that the gap reaches a reasonable value.
27. Blockage during concrete unloading
Fault phenomenon: During the unloading process of the mixer, the concrete blocks the entrance of the mixer truck and cannot enter, resulting in Concrete is blocked in the discharge hopper.
Cause analysis:
The reason for material blocking is that the material is unloaded too fast. When the mixer’s semi-open opening is too large, the concrete will be discharged too quickly. When the half-open time of the mixer is too short, the concrete will be discharged too quickly when it is turned to full open.
Processing process:
If material is blocked during the half-opening process, reduce the half-opening of the mixer discharge door. If the material is blocked when turning from half-open to full-open, the half-open time needs to be extended.
28. When transporting powder to the tank, ash comes out of the top of the tank
Fault phenomenon: During the process of pumping ash from the bulk cement truck to the powder tank , there is powder coming out from the top of the cement tank.
Cause analysis:
The powder is transported to the powder tank through compressed air. After the compressed air sends the powder to the powder tank, it is discharged to the dust collector through the filter element on the top of the tank. In the air, if the filter element of the dust collector is clogged, the compressed air cannot be discharged in time and “pressure suppression” occurs. When the pressure reaches the opening pressure of the safety valve on the top of the tank, the safety valve opens, and the compressed air and powder are discharged into the atmosphere through the safety valve. Ashing occurs. In addition, due to the failure of the material level meter, ash will also appear on the top of the tank if the powder continues to be fed after it is full.
Processing process:
（1) Check the condition of the filter element of the dust collector on the top of the tank and clean it.
(2) Once ash emission occurs, the powder around the safety valve must be cleaned to prevent the powder from being wetted by rainwater and clumping to block the safety valve.
(3) If dust is emitted due to overfilling of powder, the reliability of the material level gauge and material full alarm device must be checked.
29. The air compressor starts frequently.
Fault phenomenon: During the working process, the air compressor starts frequently.
Cause analysis:
(1) The pressure difference of the air compressor is too small.
(2) The air system leaks seriously.
Processing process:
(1) Check the pressure difference of the air compressor and adjust it, usually 0.2MPa.
(2) Check whether the air tightness of the gas line system meets the requirements, and deal with the leaking parts.
30. Belt slips in rainy days
Fault phenomenon: In rainy days, the inclined belt slips when running under load.
Cause analysis:
On rainy days, the moisture in the aggregate and the exposed parts of the belt are easy to get wet. The belt is wet, especially the inner ring, which reduces the friction between the belt and the transmission roller. The coefficient reduces the torque transmitted from the drum to the belt. When the torque is less than the torque required for material transportation by the belt, the belt will slip.
Processing process:
(1) Increase the counterweight of the belt tensioning device or tighten the belt adjustment screw to increase the positive pressure between the belt and the roller, so as to achieve the optimal balance between the transmission roller and the roller. Friction between belts.
(2) Adjust the tensioning drum near the transmission drum to increase the wrapping angle of the belt on the transmission drum and increase the friction.
(3) Cut straight grooves on the rubber coating of the transmission roller to increase the friction coefficient.
(4) If the first three methods cannot solve the problem, the anti-skid roller needs to be replaced.
31. The admixture pump does not load the admixture
Fault phenomenon: The admixture pump does not pump the admixture when it is working.
Cause analysis:
(1) There are bubbles in the admixture pump.
(2) There is insufficient material in the admixture box.
(3) The impeller of the admixture pump is damaged.
Processing process:
(1) Unscrew the admixture vent screw and discharge the bubbles in the admixture.
(2) Add admixture to the admixture box.
(3) Check the condition of the admixture impeller and replace spare parts as appropriate.
32. Belt damage
Fault phenomenon: After one end of use, degumming, cracking, scratches, etc. appear on the surface of the belt.
Cause analysis:
If the metal belt cleaner is not adjusted in time, it will easily damage the belt and cause the rubber on the belt surface to fall off. cleanerIf installed incorrectly, sharp gravel can get stuck between the cleaners and damage the belt. The belt itself is of poor quality and prone to the above defects.
Processing process:
Once the belt has defects such as degumming, cracking, scratches, etc., it should be repaired in time. When the belt is damaged, the factors causing the belt damage must be solved first. If the cleaner is damaged, the cleaner needs to be adjusted or replaced immediately, and the belt must be repaired in time. When the belt damage is very small, belt repair glue can be used to repair it on site. When the damaged area of the belt is large or the local damage is serious, the partially damaged belt can be removed, a section of the belt can be replaced, and a vulcanizing machine can be used for cementing. If the belt damage is not treated in time and the damage spreads to the entire belt, there will be no repair value and the entire belt can only be replaced.
33. The belt conveys uneven aggregates
Fault phenomenon: The materials unloaded onto the belt by the aggregate scale accumulate, causing the belt to be bulky, or There are gaps in the aggregate conveyed on the belt, resulting in pebbles and bulk materials.
Cause analysis:
The order and time interval for unloading various aggregates onto the belt in the batching station can be adjusted at any time. The general discharge sequence requires that the last aggregate to be discharged is sand, and the discharge time interval requires that the tail of the former aggregate falling on the belt coincides with the head of the latter aggregate falling on the belt. If the time interval is too short, the former aggregate and the latter aggregate will overlap and stack. Too much stacking will cause bulk materials. If the time interval is too large, there will be a gap between the two aggregates, and the former aggregate will If the material is pebbles, they will roll on the belt and scatter.
Processing process:
(1) Adjust the discharge sequence of aggregates to ensure that sand is discharged last.
(2) Adjust the unloading time interval of various aggregates according to the distribution of aggregates on the belt to ensure continuous and even distribution of materials on the belt. The time interval generally needs to be adjusted multiple times.
34. The pressure of the pressure reducing valve in the air source triple unit cannot be adjusted
Fault phenomenon: Turn the pressure reducing valve adjustment handwheel, but the pressure cannot be adjusted.
Cause analysis:
(1) The inlet and outlet directions of the pressure reducing valve are reversed.
(2) Foreign matter is embedded in the valve core or foreign matter is stuck in the sliding part of the valve core.
(3) The pressure regulating spring, return spring, diaphragm, rubber pad on the valve core, etc. are damaged.
Processing process:
(1) Check whether the installation direction of the inlet and outlet of the pressure reducing valve is correct.
(2) Disassemble and inspect the valve core and related parts, and clean the debris on the parts.
(3) If the parts are damaged, replace the pressure reducing valve.
35. The oil mist device in the air source triple unit does not drip oil or the amount of oil dripping is too small
Fault phenomenon: The compressed air flows, but the oil mist device No oil dripping or oil dripping is very small.
Cause analysis:
(1) The oil mist device is installed in the inlet and outlet direction.opposite.
(2) The oil passage is clogged.
(3) The oil filling plug gasket is damaged or the oil cup sealing gasket is damaged, so that the upper cavity of the oil cup cannot be pressurized.
(4) The air channel is blocked and the upper chamber of the oil cup is not pressurized.
(5) The throttle valve is not opened or the opening is not enough.
(6) The viscosity of the oil is too high.
Processing process:
(1) Check the installation direction of the lubricator inlet and outlet.
(2) Stop the air, disassemble and clean the oil passage; replace the gasket and seal; clean the air passage.
(3) Adjust the opening of the throttle valve.
(4) Replace lubricating oil with lower viscosity.
36. The magnetic switch on the cylinder cannot be closed or sometimes cannot be closed.
Fault phenomenon: When the cylinder is closed or opened in place, the magnetic steel is close to the departure switch. But the part-of-speech switch is not closed or sometimes cannot be closed.
Cause analysis:
(1) Power failure.
(2) Poor wiring.
(3) The installation position of the magnetic switch is offset.
(4) There is a strong magnetic field around the cylinder.
(5) The temperature in the cylinder is too high or the temperature of the magnetic switch is higher than 70 degrees.
(6) The magnetic switch is impacted and its sensitivity is reduced.
(7) The magnetic switch instantly passed a large current and was disconnected.
Processing process:
(1) Check whether the power supply is normal.
(2) Check whether the wiring part is loose.
(3) Adjust the magnetic lighting installation position.
(4) Add magnetic isolation board.
(5) Cool down.
(6) Replace the magnetic switch.
2. Precautions for equipment maintenance of concrete mixing station
When repairing equipment failure occurs in concrete mixing station, it must be repaired by professionals, and Put safety first and pay attention to the following during maintenance:
1. Before performing maintenance work on the mixing machine, you must first supervise the operator to cut off the power supply, lock the power distribution cabinet, and place a warning on the operating console You can do the work only if you have the license plate. It is strictly prohibited for the main unit to enter the machine while it is powered on.
2. Before carrying out maintenance work on the belt conveyor system, the power supply must be cut off, the power distribution cabinet must be locked, and the key must be kept by the maintenance person. When inspecting and adjusting the work, it is indeed necessary to carry out the conveyor system while it is running. Two people must be present and take preventive measures before the work can be carried out. Single person work is strictly prohibited.
3. Safety belts must be fastened when working at heights, especially when working on the powder bin. It is strictly prohibited to work at heights without safety belts.
4. When performing vehicle and loader maintenance operations, wheel weirs must be installed, and support insurance must be installed when necessary to prevent the vehicle from slipping and the jack from collapsing, injuring people or damaging equipment.
5. Maintenance electricians must wear insulating protective gear when working. Only two people can work when they are present. Single person work is prohibited. Maintenance electricians should inspect the lines, switches, and distribution boxes of the company’s electrical facilities every month, promptly rectify the identified problems, and make inspection and rectification records.
6. Welders should wear protective gear when performing welding operations and operate with caution to prevent burns or eye injuries; when performing welding on equipment without disassembling, necessary precautions should be taken. Prevent damage to other parts due to welding.
If the website content violates your rights, please contact us to delete it。
