Process control
The process control is different depending on the nature of the various processes and products. Control methods can be divided into the following groups:

Off-line measurements
- Optical comparator giving ID, Wall, OD, ovality and concentricity
- Pin gauges giving ID.
- Laser gauges giving OD and ovality.

In-line measurements
- Laser equipment giving OD and ovality.
- Ultrasonic equipment giving ID, Wall, OD, ovality and 
  concentricity.

Other in-line control systems
- Logging and simultaneous graphic display of different
  parameters such as: OD, ovality, extrusion pressure and
  temperatures, screw rpm and line speed.

Every extruder line has laser OD measurement and all extruded tubes are measured manually by the operator who has the total overall responsibility for the quality.