How to perform daily maintenance and care for injection molds?
What is an injection mold?
An injection mold is a tool installed on an injection molding machine that injects molten plastic into its cavity under high pressure. After cooling and shaping, the resulting plastic product perfectly matches the cavity shape.
As key equipment in injection molding production, injection mold maintenance is crucial for ensuring product quality, improving production efficiency, extending mold life, and reducing production costs. This manual aims to provide comprehensive, systematic, and practical guidance on the daily maintenance of injection molds, ensuring they are always in good working condition.
The Importance of Daily Maintenance
1. Ensuring Product Quality: Good mold condition ensures the dimensional accuracy, surface quality, and shape integrity of injection molded products, reducing product defects such as flash, sink marks, and deformation.
2. Improving Production Efficiency: Timely maintenance reduces the likelihood of mold failure, minimizes downtime, and improves production continuity and efficiency.
3. Extending Mold Life: Proper maintenance measures can slow the progression of mold damage, such as wear and corrosion, extend the mold's service life, and reduce mold replacement costs.
Daily Maintenance Details:
(I) Pre-production Inspection
1. Appearance Inspection:
A. Inspect the mold surface for defects such as damage, deformation, and cracks, especially in key areas such as the parting surface, gate, and ejector pins.
B. Check that the mold markings are clear and complete to ensure the mold is compatible with the production task.
2. Water Line Inspection: Connect the cooling water lines and check that the water pipes are securely connected and leak-free. Observe the smooth flow of water, which can be determined by the sound and pressure of the water flow. If the flow is poor or the water pressure is abnormal, check for blockage or pipe flattening.
3. Moving Part Inspection:
A. Manually push the slider, ejector, and other moving parts to check for smooth movement and any signs of sticking.
B. Check the ejector pin for bending or breakage, and the return spring for proper elasticity. Replace any abnormalities promptly. Check the clearance between the guide pins and guide sleeves. If the clearance is too large, it may cause inaccurate mold closing and require adjustment or replacement.
C. Fastener Inspection: Use a torque wrench to check the mold's fastening screws to ensure that the preload meets the required level. This prevents loose screws from causing mold displacement or deformation during the injection molding process.
(II) Production Process Monitoring
1. Injection Molding Parameter Monitoring: Closely monitor parameters such as injection pressure, injection speed, holding pressure, holding time, and cooling time to ensure they are within the mold's applicable range. Abnormal parameter fluctuations may cause impact and wear on the mold, shortening its lifespan.
2. Mold Condition Observation:
A. Regularly observe the mold during the opening and closing process for any abnormal noise, vibration, or jamming. If any abnormality is detected, immediately stop the machine for inspection and troubleshooting.
B. Monitor mold temperature fluctuations. This can be achieved by measuring the mold surface temperature or monitoring the cooling system's return water temperature to ensure uniform mold temperature and avoid localized overheating that could cause mold deformation or material performance degradation.
3. Product Quality Inspection: Inspect the quality of injection-molded products at a regular frequency. If problems such as flash, missing material, bubbles, or difficulty demolding are found, these issues may be related to mold condition. Promptly analyze the cause and implement appropriate measures, such as adjusting mold clearance, cleaning venting slots, and optimizing the injection molding process.
(III) Post-Production Cleaning and Maintenance
1. Residue Cleaning:
A. After injection molding, promptly clean plastic residue from the mold cavity, core, runner, gate, and other areas. Use a copper brush, soft cloth, or dedicated cleaning tools; avoid scratching the mold surface with steel tools. For stubborn residue, use an appropriate mold release agent or cleaning agent to assist in cleaning. However, be mindful of the corrosive nature of the cleaning agent to avoid damage to the mold.
B. Clean areas prone to residue accumulation, such as ejector pin holes and slider slots, to ensure the proper operation of moving parts.
2. Mold Surface Cleaning: Use a clean, soft cloth or lint-free paper dampened with an appropriate amount of mold cleaning agent to wipe the mold surface to remove contaminants such as oil and dust. For mirror-finish molds, use a dedicated mirror cleaner and a soft wiping tool to prevent scratches.
3. Lubrication and Maintenance:
A. Lubricate moving parts such as ejectors, guide pins, sliders, and lifters. Choose an appropriate lubricant, such as high-temperature grease or mold-specific lubricant. Determine the frequency and amount of lubrication based on the operating conditions and requirements of the moving parts. Generally, lubrication should be performed after each production run or regularly (e.g., weekly).
B. When applying lubricant, ensure that the surface of the moving parts is evenly covered, especially in friction areas and fitting clearances. Be careful to avoid applying excessive lubricant to prevent product contamination or affecting the mold's air venting performance.
4. Rust Prevention:
A. If the mold will not be used for a short period of time, perform rust prevention. Spray rust prevention oil evenly on the mold surface, especially in areas prone to rust, such as parting surfaces, cooling water channel holes, and ejector pin holes. Molds that are not in use for an extended period can be wrapped with rust-proof paper or plastic wrap to isolate them from air and moisture and prevent rust. B. The mold storage environment should be kept dry and well-ventilated to avoid moisture and corrosive gases. If the ambient humidity is high, consider using a dehumidifier to reduce it.
IV. Maintenance Tools and Materials
1. Cleaning Tools: Copper brush, soft cloth, dust-free paper, brush, special mold cleaning agent, mold release agent, compressed air gun, etc.
2. Inspection Tools: Torque wrench, caliper, micrometer, surface roughness tester, thermometer, hardness tester, etc., for checking mold dimensional accuracy, surface quality, temperature, hardness, and other parameters.
3. Lubricants: High-temperature grease, mold-specific lubricant, molybdenum disulfide lubricant, etc. Select the appropriate lubricant based on the operating conditions and requirements of the mold's moving parts.
4. Rust-Preventive Materials: Rust-Preventive oil, anti-rust paper, plastic wrap, desiccant, etc., for preventing mold, rust and corrosion.
V. Maintenance Records and File Management
1. Record Content: Detailed information should be recorded for each maintenance session, including the time, operator, maintenance items, any problems found and their resolution, and any replaced parts. At the same time, relevant data such as the number of production runs, usage time, and any failures should also be recorded.
2. Record Form Design: Design a standardized maintenance record form for easy completion and recording by operators. The form should include columns such as mold number, maintenance date, maintenance item, maintenance results, and notes.
3. File Management: Organize maintenance records into a file to create a mold maintenance file. Files should be categorized and stored by mold number for easy access and traceability. By analyzing maintenance records, you can identify mold usage patterns and common problems, providing a basis for developing a more effective maintenance plan.
VI. Precautions
1. Operating Standards: Maintenance personnel must undergo professional training and be familiar with the mold's structure and performance, mastering proper maintenance methods and operating procedures. When performing maintenance work, they must strictly adhere to safety operating procedures to prevent accidents.
2. Tool Use: Use appropriate tools for maintenance to avoid damage to the mold caused by improper tooling. For example, when disassembling and installing mold components, use dedicated disassembly tools and avoid directly striking the mold with hard objects such as hammers.
3. Material Selection: Choose materials of reliable quality that meet mold requirements for cleanliness and lubrication.
As a manufacturer of production equipment for heating elements, small appliances, and kitchenware, Davinci Machine provides customers with one-stop solutions, encompassing turnkey projects from production equipment, molds, raw materials, and production line guidance. If you're interested in injection molds, metal molds, and die-casting molds for these applications, we're your free consultant!
Foshan Davinci Technology Co., Ltd
Website: www.davinci-machine.com
Whatsapp/Wechat/Phone:+8618029293151
Email：sales1@vincienegy.com
Jenny Yao
