No-Dig Live Exhibition


Indoor 123
2 Stewart Street
East Dunbartonshire
G62 6BH
United Kingdom

If you have any questions, please get in contact with us.

Steven Brogden

Full informa

The process involves elastically reducing the diameter of the liner pipe at ambient temperature enabling the thermoplastic (usually PE 100) liner pipe to be installed as a tight-fitting liner within a host pipe. 

Load applied to the liner through a reduction die enables utilisation of the viscoelastic properties of the polymer material. As the liner passes through the die it is elastically reduced diametrically and elongated axially while tension is maintained (cold drawing). The reduced diameter needs to be designed so that there is adequate clearance between the outside diameter of the liner and the inner diameter of the rigid host pipe.

Once tension is removed the stored energy in the liner causes the liner to revert elastically in the axial direction providing diametric recovery which produces a tight fit on the bore of the host. The strain on the liner is comprised of both elastic and inelastic components resulting in a tight-fitting liner with a reduced diameter to that of the original liner pipe.

The proportion of elastic and inelastic strain is dependent on the outside diameter of the liner and the die size. This results in multiple design possibilities, enabling optimisation for specific installation conditions. As design depends on the complex viscoelastic strain behaviour of the polymeric thermoplastic it is not simple to calculate, this is where Die Draw can help.

We enable Contractors to use the technology for themselves by offering:

  • Technology selection for application and location
  • Liner design and design control
  • Equipment specification and design
  • Liner installation and reversion procedures
  • Inspection of installation set-up
  • On-site support
  • Contingency planning


Located in: Exhibitors 2021