1000 ton injection molding machine Precautions for use

Pre-start-up Inspection

Mechanical Parts: Check whether there are any foreign objects blocking the moving parts such as the clamping unit, injection unit, and ejection device of the injection molding machine, and whether the bolts at each connection point are tightened. For example, check whether there are any residual plastic fragments or tools between the plates of the clamping unit.

Hydraulic System: Confirm whether the oil level of the hydraulic oil is within the normal range and whether the oil quality is good. Observe whether there is any leakage in the hydraulic oil pipes, because hydraulic oil leakage will not only affect the performance of the machine but may also cause safety hazards. Meanwhile, check whether the hydraulic power sources such as oil pumps and motors are operating normally and whether there is any abnormal noise.

Electrical System: Check whether the connections of the electrical components in the electrical control cabinet are firm and whether there are any damages, aging, etc. in the wires. Ensure that all operation buttons, switches, and indicator lights can work properly, and that the grounding protection device is reliably grounded to prevent electric shock accidents.

Mold Installation: When installing the mold, make sure that the installation dimensions of the mold match those of the injection molding machine. The mold should be correctly installed on the plates of the injection molding machine, precisely positioned by the locating ring, and fastened with appropriate bolts. After installation, it is necessary to check whether the opening and closing movements of the mold are smooth.

Key Points to Note During Operation

Parameter Settings

Temperature Control: Set the temperatures of each section of the barrel according to the characteristics of the plastic raw materials used. Different plastics have different processing temperature ranges. For example, the general processing temperature range of polypropylene (PP) is about 180 - 240 °C, while that of polycarbonate (PC) is about 250 - 300 °C. If the temperature is too high, it may cause the plastic to decompose, and if it is too low, the fluidity of the plastic will be poor, affecting the molding quality.

Pressure Control: Reasonably set the injection pressure, holding pressure, and clamping pressure. The injection pressure should be determined according to the fluidity of the plastic, the shape and size of the product, etc. If the injection pressure is too high, it may cause flash, overflow of the product, or even damage to the mold; if it is too low, it may lead to insufficient filling of the product. The holding pressure is mainly used to compensate for the volume change caused by the cooling and shrinkage of the plastic to ensure the dimensional accuracy and density of the product. The clamping pressure should ensure that the mold is tightly closed during the injection process to prevent the plastic from overflowing, but it should not be too high to avoid damaging the mold.

Speed Control: It includes injection speed, mold opening and closing speed, and ejection speed. The injection speed will affect the flow state of the plastic in the mold. For thin-walled products, a relatively high injection speed may be required to ensure complete filling. If the mold opening and closing speed is too fast, it may cause the machine to vibrate and damage the mold and machine parts. The ejection speed should also be moderate to avoid damaging the product.

Material Handling

Raw Material Drying: Many plastic raw materials need to be dried before processing to remove moisture. For example, for plastics with strong hygroscopicity such as nylon (PA), if the moisture content is too high, bubbles will be generated during the processing, affecting the quality of the product. Usually, a dryer is used to dry the raw materials, and the drying temperature and time are determined according to the characteristics of the raw materials.

Feeding Operation: During the feeding process, make sure that the raw materials are evenly added to the barrel to avoid overfeeding or underfeeding. Overfeeding may lead to excessive pressure in the barrel, while underfeeding may result in insufficient injection volume. Meanwhile, pay attention to preventing foreign objects from being mixed into the raw materials, such as metal impurities, because they may damage the screw and the barrel.

Safe Operation

Protective Devices: During the operation of the injection molding machine, all protective doors should be kept closed. Protective doors are usually equipped with safety switches. When a protective door is opened, the machine will automatically stop relevant dangerous actions, such as injection actions and clamping actions. Operators are not allowed to remove or short-circuit safety protective devices at will.

Personnel Operation Specifications: Operators should wear personal protective equipment, such as work clothes and work shoes. It is strictly prohibited to reach into the mold area or the moving range of the moving parts during the operation of the machine to prevent accidents such as being pinched or scalded. When cleaning the mold or dealing with faults, it is necessary to stop the machine first, cut off the power supply, and wait until the machine has completely stopped moving and the pressure has been released before proceeding with the operation.

Maintenance and Care After Shutdown

Cleaning Work: After shutting down the machine, it is necessary to clean the injection molding machine. First, shoot out or clean up the remaining plastic raw materials in the barrel to avoid decomposition or deterioration of the raw materials due to long-term stay in the barrel. Meanwhile, clean the plastic residues, oil stains, etc. on the surface of the mold. Special mold cleaning agents and tools can be used for cleaning.

Equipment Inspection: After shutdown, check all parts of the machine, including the wear condition of the moving parts, the pressure retention condition of the hydraulic system (if there is an abnormal drop, it may indicate that there is a leak in the system), the connection condition of the electrical system, etc., and make good records so as to detect potential problems in time and carry out repairs.

Mold Maintenance: If the mold will not be used for a long time, it is necessary to apply anti-rust oil on the surface of the mold to prevent it from rusting. Meanwhile, for molds with moving parts, such as sliders and ejector pins, appropriate lubricants can be added to ensure their flexibility. And store the mold in a dry and well-ventilated place.