Injection molding machine maintenance manual: solutions to 14 problems in clamping part

Time:2022-05-14 08:24:33 / Popularity: / Source:

1. No mold locking

Approach:
Check safety door front travel switch and repair it.
Check 24V5A power supply in electrical box, replace fuse and power supply box.
Check if spool is stuck and clean spool.
Check if I/O board has output and if solenoid valve is energized.
Check whether hydraulic safety switch is pressed and whether mechanical lock lever baffle is opened.

2. Mould opening and closing machine wringing noise

Approach:
Check whether lubricating oil pipe is disconnected, if so, oil pipe must be reconnected.
If amount of lubricating oil is small, increase amount of lubricating oil. It is recommended to fill 50 molds with oil once or add enough lubricating oil manually.
Clamping force is large, check whether mold needs a large clamping force, and reduce clamping force.
Adjust current of amplifying board, check whether current parameters meet acceptance criteria, and re-adjust current value.
If parallelism is out of tolerance, use a dial indicator to check whether parallelism of the first and second plates is greater than acceptance standard; adjust parallelism.
Injection molding machine maintenance 

3. Wait a few seconds before opening mold

Approach:
Starting speed is slow, check whether screw damping is too large, and adjust screw damping hole.
Middle hole of damping screw is too large, check whether damping of Y hole screw is too large, and replace damping screw with a thin central hole.

4. Crawling of mold opening and locking

Approach:
Second plate guide rail and Colin column are worn out, check second plate guide rail and Colin column, replace second plate copper sleeve, Colin column, and add lubricating oil.
Improper adjustment of speed and pressure of mold opening and locking. When flow rate is set to 20 and pressure is 99, second mold clamping plate should not crawl. Adjust flow proportional valve hole, or the pilot valve hole, and adjust linear current value of proportional valve.
There is air and exhaust in pipes and cylinders.

5. Mold can not be opened

Approach:
Increase mold opening and locking speed, if pressure flow is too small and not adjusted properly, check mold opening and locking speed and whether pressure is appropriate, increase mold opening and locking pressure and speed.
Zero position of clamping electronic scale is changed, check whether clamping and straightening machine ends at zero position after twisting, and re-adjust zero position of electronic scale.
Check for reverse hinges.

6. In automatic production, mold adjustment will become tighter or looser

Approach:
There is leakage in mold adjusting solenoid valve, check whether solenoid valve is "O" type;
Check whether there is a mold adjustment action when manually playing other actions, and see if valve is stuck.

7. When other actions are working after mold clamping, mold will be fully automatically opened slowly.

Approach:
If oil plate leaks, check or replace express clamping valve and replace oil plate.
If the mold opening valve leaks, start oil pump and stop mold clamping. Press injection table or injection action to check whether second plate moves backward. Replace mold opening oil valve. It is normal to open and lock mold and not move.

8. There is only mold opening action during mold clamping

Approach:
If wiring is wrong, check if there is 24VDC to the valve, check wiring and connect wiring.
If valve is stuck or wrong valve core is installed, check whether valve core is wrongly installed or blocked, and then re-install valve core or clean it. Under normal circumstances, action of opening and locking mold is not moving.

9. Poor mold clamping

Approach:
A and B holes are not properly adjusted, set system flow to 20 and pressure to 99, observe whether clamping action crawls, readjust or replace valve.
There is air in oil circuit, listen to sound of air in oil circuit, check whether there are air bubbles in oil, and need to exhaust.
Ramp-up and ramp-down adjustment of amplifier board is improper, observe whether current value of ammeter is proportional to rise and fall or rotation speed, and adjust amplifier board.

10. Clamping can not afford high pressure, exceeding stroke

Approach:
If limit switch exceeds limit, check whether mold adjustment is appropriate, adjust appropriate mold thickness; check whether motor is in normal state.
If hydraulic limit exceeds stroke, check whether stroke position of electronic ruler is appropriate, check whether mold adjustment is appropriate, and adjust mold forward appropriately.

11. Manual with mold-opening termination, semi-automatic without mold-opening termination

Approach:
If mold opening valve leaks, move after manual shooting table, observe whether second plate moves backwards, and replace mold opening valve.
Check maximum stroke and pressure flow of electronic scale.
Crawling of mold opening and locking 

12. No thimble action

Approach:
Thimble limit switch is broken, use a multimeter to check whether 24V proximity switch is on. Replace thimble limit switch.
If valve is stuck, use a hexagonal key to press thimble valve core to see if it can move, and clean pressure valve.
Limit rod of thimble is broken. After machine stops, take out limit rod by hand and replace limit rod.
Thimble switch is short-circuited, check 0 voltage of thimble switch to ground with a multimeter, and replace thimble switch.
Position of electronic ruler is not set properly.

13. Thimble out of control when semi-automatic

Approach:
Thimble board is broken, check whether line is normal, normal voltage is DV24V. Repair thimble plate.
If wire is broken, check connection wire of switch and connection wire on I/O board. Check wiring and rewire.
Check whether mold is out of position.
Whether cylinder piston rod seal is damaged.

14. Loud sound when opening mold

Approach:
Proportional linearity is poor, pressure flow at the time of mold opening and closing is poorly adjusted. Check ramp up and ramp down in parameters, adjust ramp up and ramp down in parameters.
Clamping machine hinge is poorly lubricated, check Colin column, second plate sliding foot, and lubrication of machine hinge, increase lubrication, and increase number of oiling.
Clamping force of mold is too large, check clamping force when mold is stressed, and reduce clamping force according to user's product conditions. Check that time position is appropriate.
Deviation of parallelism of head and second plate, check parallelism of head and second plate. Adjust parallel error of second board and head board.
Setting position of slow-speed rotation and rapid mold-opening is too small, and speed is too fast. Check whether position of slow mold opening to fast mold opening is appropriate, and whether slow mold opening speed is too fast. Lengthen slow mold opening position and reduce slow mold opening speed.

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