Requirements of Daily Maintenance

Part I Requirements of Daily Maintenance
For high performance and long service life, the machine should be checked regularly and repaired accordingly.

I. Maintenance and Checking of Hydraulic Device

In fact, more than 70% of the failures of the hydraulic device are caused by the pressure oil. In order to reduce failures and make sure that the hydraulic system is working well, the pressure oil, air filter, oil filter and radiator should be maintained and checked.

1.1 Checking the Pressure Oil

After being used for six months, 100CC pressure oil from the oil tank should be sent to the laboratory for checking. If the pressure oil is found bad, it should be replaced at once. After running for three months, the pressure oil of the new machine should be replaced. Then replace the pressure oil once a year. Pay attention to the following items when replacing or adding pressure oil:

i. The pressure oil added should be completely same as that in the hydraulic system. The reason lies in that after mixing, the different pressure oil will cause chemical reaction and hence the quality of the oil will be affected.
ii. If the pressure oil is decreased for unknown reasons, before adding the pressure oil, the reasons should be found out first.
iii. The oil in the oil tank should be drawn out completely and the oil tank should be cleaned before it is replaced.
iv. The tube used for adding oil should be kept clean.
v. The pressure oil shouldn’t be added directly, the filter screen should be used.
vi. Rags can not be used for cleaning, for the batt left will block the screen of the filter.

1.2 Checking Air Filter

The top of the oil tank is equipped with air filter, which can also be used as an oil inlet. The air can come in and out easily by the adjustment of the air filter according to the level of the oil. Each time after adding pressure oil, the air filter should be taken out and put on the container, clean it by gasoline and dry it by compressed air.

1.3Checking Oil Filter

After the machine has run for two weeks, the oil filter should be taken out for cleaning. Put the filter on a container and add some gasoline, brush the filter screen and dry the screen by compressed air. Then clean it every three months so that oil suction hose be kept expedite. If the filter screen is blocked, the pump will cause noises.

1.4Checking the Cooler

After using for a period of time, furring will be adhered to the inner wall of the radiant pipe of the cooler, which will cause lower heat transfer efficiency hence the pressure oil level will be raised. Therefore, the cooler should be cleaned every six months.

1.5 How the Temperature Affects the Pressure Oil

When injecting plastic, the temperature of the pressure oil should be kept between 30 degrees to 50 degrees. If the temperature is too high, the phenomena below can be found:

i) Oxidation will be accelerated, which will make the pressure oil bad
ii) If the consistency of the oil becomes lower, the lubricating effect will be worse, and the pump and oil switch will be damaged.
iii) The oil seal ring will be hardened and the seal effect will be worse. .

II. Maintenance and Checking of the Lubricant

The clamping unit is an important lubricating point,. Because of friction for a long time, the parts will, if deficiency of lubrication be damaged, this will affect their performance and quality.


Note: Do not use the pressure oil as lubricant because their viscosities are different. Otherwise the reamer will be damaged.

III. Maintenance and Checking of the Clamping Unit

The moving or turning part of the clamping unit will be damaged because of deficiency of lubricant. The damages or failures can be decreased if you can pay attention to the providing of the lubricant to all parts of the clamping unit and the screws. Moreover, you should also pay attention to the notices as below:

i) Enough lubricant to prevent the reamer from being damaged.
ii) Check the transparent lubricating tube of lubricating system where the reamers are centered to see if it is expedite and no disjunctions or damages.
iii) Check regularly if there is wear and tear of reamer or leakage of iron powder.
iv) Keep the boot guide rail of the moving mould clean and lubricate.
v) Keep the surface of the four columns clean.
vi) Do not use bad moulds, which will damage the reamers and break the columns.
vii) Do not use too strong clamping force, which will deform the mould or molding chamber and damage the reamers, moulds and column or shorten their service life.
viii) Do not use too small mould, which will create too much buckling strength and will cause the crack of the mould board.

IV). Maintenance and Checking of the Plasticizing Barrel

Notices are as below:
i) Do not activate the plasticizing motor before the plasticizing barrel has reached the pre-set temperature.
ii) When using the upside rope, make sure that the plastic in the melting rubber is melted completely. Otherwise the rubber kit or the components of the transmission system will be damaged when the screw is fallen back.
iii) Except plastic and additives, do not put anything into the hopper. If the material is used in large quantities, the hopper magnet should be added to prevent the metal fragments from entering into the plasticizing barrel.
iv) When disassembly or replace the nozzle, rubber ring, injection particle and fixing screws on the head, the lubricant should be added which can resists high temperature. Otherwise, the screw will be oxygenated and it will be difficult to disassembly.
v) When using such plastic as PVC or POM-,etc, inject all the plastic before the machine is stopped. Then clean the plasticizing barrel with such plastic as PE or PP.
vi) When the plasticizing temperature is normal but black dots or color changing occurs, check whether the injection screw, rubber ring or injection particle are damaged or not.
vii) Check the screws of the injection piston bar periodically if it becomes loose.

V. Maintenance and Checking of Other Units

5.1 Checking of Electric Motor
1) The normal electric motor radiates heat by the form of air cooling. Too much dirt will cause difficulty in the radiation of heat. Clean the outer structure and fans annually.
2) If there are noises caused by the electric motor, check if the bearing is damaged. Replace it if it is broken.
3) Use the wattmeter of 500V to check if the insulation resistance of the loop is above 1M|.

5.2 Checking adjustments of the thickness of the mould
The device for mould thickness adjustment should be used periodically. Adjust the mould from the thinnest to the thickest to make sure the action is smooth. The check is necessary if you use the machine with the same mould for a long time so that it can prevent the mould from damages. At the same time, add grease (yellow grease) on the gear wheels and the chains for adjusting moulds.

5.3 Checking Lifter and Unscrew Device

i) Check whether the outer side of the compressed soft tube is damaged.
ii) Check whether the connectors of the compressed soft tube are loose.

Part II Regular Checking and Maintenance

To make sure that the machine is running well and has lesser failures and higher performance, longer service life, safer running and shorter out of service time cause by the failures, the machines should be checked and maintained regularly. The maintenance and check can be divided into daily, weekly, monthly, every half year and annual check.


Appendix: Adjustments of the nozzle center
The nozzle center has been adjusted in the factory. Do not adjust them if the plasticizing barrel or injection screw need not be replaced.

Adjustment steps:
1)Prepare a caliper. If the mould has been assembled, disassemble it first.
2)Press the button of° Forward±, make the injection unite move to the nozzle and kept the same level as the mould plate. Loose the four bolts that fixed the injection unite.
3)Use the caliper to check if the horizontal distance and vertical distance between the nozzle center hole and the position circle of the mould fixing plate.
4)If the horizontal distances are different, use some tools (for example, spanner) to adjust it, making the nozzle as a force point and the center hole of the cephalic plate as fulcrum.
5)If the vertical distances are different, adjust slightly the four bolts that adjust the height.
6)Check again the horizontal distance and vertical distance between the nozzle center hole and the position circle of the mould fixing plate. Redo step 4 and 5 if necessary.
7)Re-fix the four fixing bolts.