about Injection mould Maintenance suggestions

Compared with other molds, injection molds are more complex and precise in structure, and have higher requirements for operation and maintenance of products. Therefore, in the entire production process, the use of positive solutions and careful maintenance are of great significance for maintaining normal production and improving enterprise efficiency.

1、 Select appropriate molding equipment and determine reasonable process conditions. If the injection molding machine is too small, it can not meet the requirements. If it is too large, it is a waste of energy, and it will damage the mold or template due to improper adjustment of the clamping force, at the same time, it will reduce the efficiency.

When selecting the injection machine, it should be checked according to the larger injection volume, the effective distance of the pull rod, the installation size of the mold on the template, the larger mold thickness, the smaller mold thickness, the template stroke, the ejection method, the ejection stroke, the injection pressure, the mold closing force and other items, and it can be used only after the requirements are met. Reasonable determination of process conditions is also one of the contents of correct use of molds. Too large clamping force, too high injection pressure, too fast injection rate, and too high mold temperature will damage the service life of molds.

2、 After the mold is installed on the injection machine, empty mold operation shall be carried out first. Observe whether the operation of each part is flexible, whether there is any abnormality, whether the ejection stroke and opening stroke are in place, whether the profile is closely matched when closing the mold, and whether the pressing plate screws are tightened.

3、 When the mold is used, it should be kept at normal temperature. Working at normal temperature can extend the service life of the mold.

4、 The sliding parts on the mold, such as guide pillar, needle return, push rod, core, etc., should be observed at any time, checked regularly, scrubbed and filled with lubricating grease at the right time. Especially when the temperature is high in summer, oil should be added twice less per shift to ensure that these sliding parts can move flexibly and prevent tight seizure.

5、 Before locking the mold each time, pay attention to whether the mold cavity is cleaned, and no residual products or any other foreign matters are allowed to remain. It is strictly prohibited to use hard tools to clean the cavity surface to prevent damage.

6、 For molds with special requirements on the surface of the cavity, the surface roughness Ra is less than or equal to 0.2cm, which cannot be wiped by hand or with cotton wool, but should be blown with compressed air, or gently wiped with high-grade napkins and high-grade absorbent cotton dipped in alcohol

7、 The surface of the mold cavity should be cleaned regularly. During the molding process, the injection mold often decomposes low molecular compounds to corrode the mold cavity, making the bright cavity surface gradually dull and reducing the quality of products. Therefore, it needs to be cleaned regularly. Alcohol or ketone preparations can be used to scrub and then blow dry in time

8、 When temporary shutdown is required after operation, the mold should be closed to prevent the cavity and core from being exposed to prevent accidental damage. The shutdown time is expected to exceed 24 hours, and the surface of the cavity and core should be sprayed with antirust oil or release agent, especially in humid areas and rainy seasons. Rust prevention treatment should be carried out even if the time is short.

The water vapor in the air will reduce the surface quality of the mold cavity and the surface quality of the product. When the mold is used again, the oil on the mold should be removed, and it can be used only after it is wiped clean. The cleaning compressed air with mirror requirements should be dried and then dried with hot air, otherwise, the product will leak out during molding and cause defects.

9、 Start the machine after temporary shutdown. After opening the mold, check whether the slider limit moves. If no abnormality is found, the mold can be closed. In short, you must be careful before starting the machine.

10、 In order to extend the service life of the cooling water channel, when the mold is out of service, the water in the cooling water channel should be immediately removed with compressed air, a small amount of engine oil should be put into the nozzle mouth, and then compressed air should be used to blow, so that all cooling pipes have a layer of antirust oil layer.

11、 Carefully check the working status of each control component during work to prevent abnormalities of auxiliary system. Heating and maintenance of control system are particularly important for hot runner mold. At the end of each production cycle, the rod heater, belt heater and thermocouple shall be measured and compared with the technical description of the mold to ensure the integrity of its functions. At the same time, the control circuit may be tested by an ammeter installed in the circuit. The oil in the hydraulic cylinder for core pulling shall be drained as far as possible and the nozzle shall be sealed to prevent the hydraulic oil from leaking or polluting the surrounding environment during storage and transportation.

12、 In case of abnormal sound or other abnormal conditions in the production, the machine shall be stopped immediately for inspection. The mold maintenance personnel shall carry out patrol inspection on the molds that operate normally in the workshop, and timely handle any abnormal phenomenon found.

13、 In addition to the record of production handover and critical process, the operator should also have a detailed explanation of the use of the mold during shift handover.

14、 When the mold has completed the production quantity of products and needs to be dismounted to replace other molds, the mold cavity should be coated with anti rust agent, the mold and its accessories should be sent to the mold maintainer, and the qualified products of the next mold should be sent to the maintainer together as samples. In addition, a mold use list should also be submitted to fill in the details of what machine tool the mold is on, how many products are produced from a certain date, and whether the mold is in good condition. If there is a problem with the mold, fill in the use sheet of the mold, put forward specific requirements for modification and improvement, and submit an untreated sample of the mold to the storekeeper for reference when the mold repair.

15、 The mold warehouse shall be set up, managed by specially assigned person, and the mold file shall be established. If possible, the mold shall be managed by computer. The mold warehouse shall be located in a place with low moisture and ventilation, and the temperature shall be kept below 70%. If the humidity exceeds 70%, the mold is easy to rust. The mold shall be stored on shelves, and attention shall be paid to corrosion prevention and dust prevention. Mark the identification of repair or completion of repair and maintenance.