Injection molds for Electrical Appliances

Plastics having very good electrical insulating properties, light weight, weight to strength ratio and antirust properties increases its use in electrical appliances. Electrical parts vary from very simple to very complex single shot to two shot. Both rubber and plastic is used. Aesthetic look is required for domestic. On these bases the molds for electrical appliances are very simple two plate to complex with sliders and inserts. Surface finish is also important in these devices. Printed plastic now a days used with different graphics printed on these device that add a new look to device.

List of electrical appliances:

1. Plastic Housing
2. Plastic Body
3. Plastic Boxes
4. Plastic Casings
5. Plastic Connector
6. Switches and gears
7. Plastic Sockets
8. Plastic Hubs
9. Plastic Buttons

• Plastic Bridges

Mold specifications for electrical Appliances

Electrical appliances molds are specified according to their end use. Injection molds for electrical should have

1. Low cycle time
2. Even cooling system
3. High rate of production
4. Corrosion resistant
5. Product without any stresses
6. Product according to requirements

Designing of mold

Design engineer design the mold with the help of designing tools and software. There are two stages in designing. 1st Product designing and 2nd mold designing. Plastic product is designed in CAD software and then it is converted to CNC machine language by using a CAM software. CAE (computer aided engineering) software like mold flow is used simulate the mold in real like environment. By CAE flow of molten plastic in the mold is simulated, cooling of product and any other defect can be analyzed that can cause a major problem during real run of mold. After this machining of mold starts.

Mold materials

Mold is fabricated by combining different parts together. These different parts are made from different type of materials. Like Base of molds mostly made from P20 pre-hardened tool steel and core and cavity are made from hardened tool steel like 718, NAK80, H13,S45C, 2311, H13, 2344, Starvax 420, 236, AdC3, 2312, 2379, 2316, 2083, 2767 and others S136 have very good surface polishing capabilities.

Plastic materials for electrical Appliances

1. HDPE (High Density Polyethylene)
2. PP & CoPP (Polypropylene)
3. PC (Polycarbonate)
4. ABS+PC (Blend)
5. PA66 (Polyamide 66)
6. PU (Polyurethane)
7. PVC (Polyvinylchloride)
8. ABS (Acrylonitrile Butadiene Styrene)
9. PMMA (Poly Methyl Meth Acrylate)

The most common materials for the shell of electrical appliances are ABS, PP, ABS+PC, PVC, Polycarbonate and blends of these. ABS is the mostly used plastic as it is cheap. PC holds very good mechanical properties but its chemical resistance is not as good.