The method of joining molded products in injection moulds

Plastic molding products processed by injection moulds may need to be made into two parts and then joined together in a suitable way if they have concave shapes, etc. The joint processing methods of injection mold molding products mainly include hot melt method, instant hot melt method, hot air welding, high frequency induction heating welding method, ultrasonic welding method and dichroic forming method.

1. Hot fusion method

Hot fusion method refers to the connection between non-metal and non-metal, which is heated up to the melting point (liquid). Mainly used for film, bag and pipe fittings.

2. Instant hot fusion method

This is one of the hot bonding method, is the use of metal belt heater to heat fusion. Because the metal strip heater is very thin, heating and cooling are instantaneous, so the fused joint is neat and firm.

3. Hot air welding

Hot air welding is a method that uses preheated compressed air or inert gas to heat plastic welds and electrodes to make them sticky and weld under low pressure. Hot air welding is mainly used for the welding of polyvinyl chloride, polyolefin, polyformaldehyde, nylon and other plastics, but also can be used for the welding of polystyrene, ABS, polycarbonate, chlorinated polyeths, chlorinated polyethylene and other plastics.

4. High-frequency induction heating welding method

High frequency welding mainly uses the skin effect and proximity effect of high frequency current, so that the current is highly concentrated on the side to be welded, and then carries out pressure welding under the action of the extrusion roll. It is used for welding of thin film and thin plate.

5. Ultrasonic welding method

The ultrasonic vibration transmits the ultrasonic wave to the weldment along with the welding head. Due to the high acoustic resistance at the two welds, the interface of local high-temperature parts is melted. Under certain pressure, the two welds can achieve beautiful, fast and strong welding effect. For all the application markets, ultrasonic welding with its unique advantages - fast, efficient, clean and firm, won the recognition of all walks of life.

6. Dichroic forming method

Dichroic molding is done by alternately injecting resin into the mold from two injection molding cylinders. The first formed product is covered by the resin injected later and fused. If the resins are compatible with each other, they will bond together firmly.

Injection mold molding products need to choose the appropriate way according to the specific situation, the above has made a detailed description of each method you can refer to use. The mission of Fanstar is to master the core technology of injection molding production, communicate and analyze the technology before mold production with customers from the production needs of finished products, so that the mold delivery time is short, the service life is long, the rapid mass production and the finished product quality is excellent! Have injection mold need or related questions welcome to contact us!