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Plastic Extrusion Process Monitoring and Control

System for monitoring and process control of plastic extrusion coating of steel pipes.

The plant takes in large steel pipes, up to 82” in diameter and 6 metres in length, and applies a thick plastic coating. The pipes are then used for transporting oil overland between refineries and storage sites. The system was designed to monitor the complete plastic extrusion process and to apply supervisory control to the key elements.


Key Benefits


Plastic Extrusion Process Control


  • Closed loop control of induction coils
  • Automatic analysis of thermal image
  • Complete process monitoring
  • Improved quality of finished products

The steel pipes received at the plant are first passed through a water wash and then through a dryer before going on to a shot blasting stage. After the shot blasting, the pipe is inspected, chromated and then passed through a pair of temperature controlled induction coil ovens. It is then driven in a corkscrew fashion through to the extruder where it is coated, first with an adhesive layer and then with the plastic itself.

The system integrates a variety of new and exisiting equipment including Eurotherm controllers, West indicators, Raytek single point measurements and Dynisco indicators. By performing supervisory control of the induction heating stages, the quantity of rejected product has been significantly reduced. Having proven its worth proved the system is due to be expanded with further closed loop control and automatic monitoring of the pipe identities.

If you have an application and would like more information please contact us.