Rust can be a major issue in injection molding. Mold makers and injection mould companies know the importance of keeping molds rust-free. Rust not only affects the mold but also damages the quality of products. Preventing rust ensures smooth production and longer mold life. In this article, we’ll discuss simple ways to prevent rust on injection molds.
Why Does Rust Happen?
Rust forms when metal is exposed to moisture and air. In an injection molding factory, water is often present. Water is used to cool the molds, and sometimes it stays on the surface. Over time, this moisture can cause rust. Other factors, like humidity, can also lead to rusting. For mold makers, controlling these factors is essential.
Preventing rust helps an injection mould company avoid costly repairs. It also ensures the mold stays in good condition for a longer time. Let’s look at the best methods to stop rust from forming.
1. Keep Molds Dry
One of the simplest ways to prevent rust is to keep the molds dry. After every injection molding cycle, make sure the mold is free of moisture. Mold makers should always dry the mold immediately after use. A dry cloth or air blower can help remove any water. Some mold makers use compressed air to blow off water droplets from the mold surface. This step is easy and takes just a few minutes.
Drying the mold prevents water from staying on the surface, which can cause rust. An injection mould company should have a routine for drying molds after each use. This will greatly reduce the chances of rust forming.
2. Use Rust Preventive Sprays
Rust preventive sprays are a common solution. These sprays form a protective layer over the mold surface. This layer stops moisture and air from contacting the metal. Injection molding companies often use these sprays after cleaning the molds. The spray protects the mold during storage and between production runs.
For long-term protection, some mold makers reapply the spray regularly. It is important to choose a high-quality rust preventive spray. Many injection mould companies rely on these sprays to protect their expensive molds. This small step can save time and money in the long run.
3. Control Mold Temperature
Controlling mold temperature is another important factor. Rapid changes in temperature can cause condensation on the mold. Condensation leads to water droplets on the surface, increasing the risk of rust. Mold makers should carefully monitor mold temperature during production.
Injection molding machines often use water or other fluids for cooling. If the cooling process is too fast, condensation may form. By controlling the cooling rate, mold makers can reduce condensation. Keeping the mold temperature steady is key to preventing rust.
4. Clean and Maintain Molds Regularly
Cleaning the mold regularly helps remove any substances that could cause rust. Dust, plastic residue, and oils can collect on the mold surface. These substances may hold moisture, leading to rust spots. Mold makers should have a regular cleaning schedule.
Use soft brushes or cloths to clean the mold surface gently. Avoid abrasive cleaning tools that could scratch the mold. Scratches make the metal more prone to rust. Many injection mould companies clean their molds daily or weekly, depending on the frequency of use.
Maintenance is just as important as cleaning. Mold makers should inspect the mold for small rust spots or scratches. These spots can be treated early before they become serious problems. Regular maintenance helps extend the mold’s lifespan.
5. Store Molds in a Dry Environment
Where you store the molds matters. A dry, well-ventilated area is the best place for storing molds. Humid environments increase the chance of rust. Injection molding companies often invest in special storage areas to protect their molds.
Some mold makers use dehumidifiers in the storage rooms. These devices reduce the moisture in the air, making the environment less suitable for rust formation. For long-term storage, some injection mould companies store molds in special anti-rust cabinets. These cabinets are designed to keep moisture away from the molds.
Proper storage can make a big difference. Mold makers should always ensure their molds are in a dry, safe place when not in use.
6. Apply Protective Coatings
Applying protective coatings is another effective method. Some injection mould companies use coatings like chrome or nickel to cover the mold surface. These coatings act as a barrier, preventing rust from forming.
Protective coatings can be applied to the entire mold or just the most vulnerable parts. The coating process adds an extra layer of defense, making the mold more resistant to corrosion. Mold makers often choose this option for molds that are used frequently. This method is especially helpful in high-humidity environments where rust is more likely to occur.
7. Control the Air in the Factory
Humidity in the air can cause rust over time. Mold makers can reduce rust risks by controlling the air quality in the factory. Using air conditioners or dehumidifiers can help lower the moisture in the air. This is especially useful in humid regions.
Many injection molding companies monitor the humidity levels in their factories. If the air becomes too humid, they take steps to reduce moisture. This reduces the chance of rust forming on the molds during production and storage.
8. Avoid Prolonged Contact with Water-Based Cooling
Water is commonly used in cooling systems during injection molding. While water is efficient for cooling, prolonged contact can increase rust risk. Mold makers should carefully manage how long water stays in contact with the mold. After cooling, it’s important to quickly dry the mold surface.
Some injection mould companies use alternative cooling fluids that are less likely to cause rust. These fluids are specifically designed for cooling without rusting the mold. While they may cost more, they can save the company money on rust prevention and mold repair.