Metal separator

1、 Core functions and importance

The core function of a metal separator is:

Full detection: online and real-time detection of plastic particles passing through the detection channel.

Accurate identification: It can detect magnetic metals (iron) and non-magnetic metals (copper, aluminum, stainless steel, etc.), with a detection accuracy of up to 0.2mm (iron ball) and 0.5mm (stainless steel ball).

Automatic removal: When metal impurities are detected, a millisecond response is given, and the material containing metal is automatically separated to the waste port through a flipping plate or air blowing mechanism.

Protecting downstream: As the last barrier before the extruder, it ensures that the material entering the screw is pure and metal free.

2、 Working principle (free fall)

The most commonly used granulation production line is the free fall metal separator, which works as follows:

Material falling: Plastic particles pass through the annular detection coil of the metal separator in a free fall manner from the upper hopper or feeder outlet.

Electromagnetic induction detection: The detection coil generates a high-frequency magnetic field after being energized. When metal particles pass through, they will interfere with the magnetic field balance and generate induction signals. The controller distinguishes between ferrous and non-ferrous metals and determines the size of impurities by analyzing the strength and phase of the signal.

Signal processing and judgment: The controller compares the detected signal with the set sensitivity threshold. If it exceeds the threshold, it is determined to contain metal impurities.

Quick removal: At the moment of detecting metal, the controller triggers the removal device located below the detection channel (usually a high-speed flap valve). Quickly flip the board and guide the small portion of material containing metal into the waste port.

Quick reset: After the removal is completed, the flipping plate quickly resets to its normal position within 0.1-0.3 seconds, allowing subsequent qualified materials to continue flowing towards the qualified product discharge port without affecting the continuous flow of the main material.

3、 Main structural components

Detection head (core component):

It contains a high-sensitivity circular detection coil, which adopts the principle of electromagnetic induction and responds to both magnetic and non-magnetic metals.

The detection sensitivity is inversely proportional to the detection aperture: the smaller the aperture, the higher the accuracy. The common caliber ranges from 25mm to 200mm.

Removal device:

Flip board (standard configuration): The flip board is driven by a high-speed cylinder, with a simple and reliable structure, minimal damage to granular materials, and can minimize the loss of qualified materials.

Hopper and bracket:

Standard equipment includes a 12L storage hopper, and larger capacity can be customized according to needs.

Equipped with stainless steel brackets and discharge hoppers, it is convenient to connect with the extruder hopper.

Discharge outlet:

Qualified product export: Connect the feeding port of the extruder.

Waste outlet: Connect the waste collection container, and the removed metal containing materials can be manually sorted or recycled later.

4、 Core features and advantages of the product

Full metal detection capability: It can not only detect magnetic metals such as iron, but also non-magnetic metals such as copper, aluminum, stainless steel, zinc, tin, etc., making up for the shortcomings of permanent magnet iron removers.

Ultra high detection accuracy: It can detect iron balls as small as 0.2mm and stainless steel balls as small as 0.5mm (depending on the diameter), even small metal wires have nowhere to hide.

Fast response and elimination: The reaction time from detection to elimination is only milliseconds, ensuring accurate separation of impurities and minimizing the loss of qualified materials.

Intelligent learning and anti-interference: Equipped with product automatic learning function, it can automatically adapt to different material characteristics (such as carbon black and humid materials) and eliminate their effects, avoiding false alarms.

Compact structure, easy to integrate: With a small size, it can be directly installed above the extruder hopper or placed behind the vibrating screen without occupying additional space.

Easy to operate: Digitally set sensitivity, one click operation, with password protection to prevent accidental changes.

Statistical function: It can record the number of detections and removals, facilitating production management and quality control.

Protecting investments and reducing risks: Investing in a metal separator can effectively protect core assets such as extruder screws and molds that are worth several times or even tens of times their value.