1. Divided by function:

1) Metal detectors machine (balanced coil type): It can detect all metals such as iron, stainless steel, copper, and aluminum. The detection accuracy and sensitivity are relatively high, stable and reliable, and can not pass aluminum film.

2) Iron metal detectors machine (permanent magnet type): Only iron metal can be detected, commonly known as needle detectors. The detection accuracy and sensitivity are low, easy to interfere, and can be packaged in aluminum film.

3) Aluminum foil: Only ferrous metals can be detected, but when testing products with aluminum foil packaging, the detection accuracy and sensitivity are still high.

2. Divided by purpose:

1) Channel conveying type: Mainly used to detect products with relatively small volume, as well as small bags and boxes of industrial products, which can be connected to the production line and realize linkage.

2) Falling type: Mainly used to detect powder, small particles and granular products. Mainly used for plastic raw materials, rubber, liquid substances.

3) Pipeline type: Mainly used to detect pasty and flowing liquid substances and seal pipelines on the assembly line. It is convenient to detect and remove metal impurities in the pipeline. It is mainly used for the detection of tablets, capsules, granular (plastic particles, etc.), and powdery items.

4) Flat plate type: usually used to detect sheet, filament and other products with relatively thin thickness but relatively large width and length, such as textile fabrics and cardboard. Its primary purpose is to protect downstream equipment while improving product quality. Easy to install, it can be installed horizontally, vertically and obliquely, and can be installed almost anywhere in the production process.

5) Split type: The metal detectors machine can be separated from the upper and lower parts, which is convenient for customers to install and use. However, there is a problem that the detector needs to be assembled again after separation, and the magnetic field balance needs to be adjusted after the regular separation is assembled again.

6) At present, the most common metal detection equipment on the market is the channel conveying type. The channel of the probe is square. Generally, it is equipped with a conveyor belt mechanism with an automatic rejection device or provides an alarm signal. When the items on the conveyor belt pass through the probe, once they contain metal, they are automatically rejected or stopped. Mainly for on-line inspection of finished and semi-finished products, providing final inspection before shipment. For example: bagged materials, boxed products, etc.