Metal Separator Locations in a Plastics Plant

By Paul Fears | 14 October 2019

Determining the best location to remove metal in a Plastics Processing plant can be difficult.  To assist plastics engineers, Bunting has released a Typical Plant Flowsheet showing optimum locations for metal separators.  This blog focuses on the locations, designs and types of Magnetic Separator and Metal Detector commonly used in plastics plants.

A Typical Flowsheet

Perfect Plastics Plant

On the flowsheet, the Plastics plant is divided into different areas and identifies optimum locations to remove metal.  In many cases, a combination of Magnetic Separator and Metal Detector is recommended as the Magnet captures and holds ferrous metal (the vast majority of metal contamination in any plant).  This leaves the Metal Detector to focus on removing the more difficult non-ferrous metals whilst minimising product loss and production downtime.

The Equipment

The type and suggested location of Metal Separation equipment is as follows:On the primary feed into the Bulk Storage Silo to remove metal before it enters the process:

Primary Feed into Bulk Storage Silo to remove metal before it enters the process:

Bunting Magnetics In Line Magnet
In Line Magnet

From the Bulk Storage Silo to capture any metal from the storage silo:

  • Drawer Magnet for ferrous metal removal;
  • Pneumatic Inline Magnet (PIM) for ferrous metal removal;
  • Bullet Magnets for ferrous metal removal

On the Moulding Line to protect processing equipment;

On the 1st Extruder to protect processing equipment:

FF Grate Magnet
A Bunting FF Grate Magnet included in a plastics production line at the Polymer Training and Innovation Centre in Telford

On the Hot Runner System to protect processing equipment:

Molding (just in time material handling) to protect processing equipment:

  • Torpedo Magnet to remove ferrous metal;
  • Machine Mounted All-Metal Separator to remove all metals;

On the 2nd Extruder to protect processing equipment:

On the Regrind Line to remove metal introduced during reprocessing:

Pneumatic Inline Magnet for ferrous metal removal;

  • pTRON 05 Metal Detector to remove all metals;
  • Plate Magnet for ferrous metal removal;
  • HS Metal Detector to remove all metals;

On the Cleaning Station as a final metal removal stage

  • Duplex Separator

The type and design of Magnetic Separator and Metal Detector and the recommended location has been determined following several decades of working with plastics producers and processors all over the world.  There are always variations to plant designs and layouts that mean different types of Metal Separation equipment is needed and an onsite review by a Bunting engineer will help ascertain the best solution.

Other relevant plastic industry articles

For further information on removing Metal from a plastics processing plant using Magnetic Separators and Metal Detectors, please contact the Bunting technical sales team on:

For additional information on removing metal from plastic please contact us on:


Via the website

Telephone:  +44 (0) 1527 65858

All product photographs by Paul Fears Photography

Follow us on social media