Cold Runner & Hot Runner Plastic Mold

Types of Runners in Injection Moulding

Generally, the temperature-sensitive wire is composed of steel wire insulated with a heat-sensitive material, the temperature sensing wire is commonly known as the "thermocouple", and there are many types, but hot runner thermocouple has two types: standard type J and type K.

Hot Runner and Cold Runner Plastic Mold Types

Multi Cavities Hot Runner Injection Mold

The hot runner will keep the plastic material in liquid in runner and injection gate, the temperature in injection machine barrel and runner are very high which can keep the material in liquid, due to there is heating system surrounded, it will only need to heat the hot runner to request temperature before production, and the hot runner is like the extension of injection machine barrel.

Cold Runner Mould

Compared with the runner plastic molding, a cold runner mold does not require a special heating system for the runner system. It will be cooled with the product together and taken out after injection finishing, and then cut the runner, the cold runner mold is what we often call the traditional mold.

Switch Cover Injection Mold

The K-type thermocouple is a metal thermocouple with strong oxidation resistance, which can measure the medium temperature of 0~1300℃, suitable for continuous use in oxidizing and inert gases, the short-term use temperature is 1200°C, and the long-term use temperature is 1000°C, the relationship between thermoelectric potential and temperature is approximately linear, and it is currently the biggest thermocouple.

Transparent PC Plastic Injection Molding

Type-J thermocouple, the positive electrode of this thermocouple is pure iron, and the negative electrode is constant (copper-nickel alloy).

Common Hot Runner Temperature Sensing Wires Types And Characteristics

However, the basic principle is to use the corresponding relationship of a certain material to temperature changes, and a closed-loop is formed by two different component material conductors, when there is a temperature gradient at both ends, at this time, there is the electromotive force-term electromotive force between the two ends, which is called "Seebeck effect". After the electric potential signal is amplified by the amplifying circuit, it is converted into an AD signal and displayed by LED or pointer, thermocouple is one of the commonly used temperature detection elements in the industry.

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