Introduction: The scope of work for this second stage is split into discrete Tasks:

TASK 1 – Investigate Liner Collapse Mechanisms

The purpose of this task is to develop greater understanding of liner collapse mechanisms and installation, and findings used to develop requirements for the Finite Element Analysis (FEA).

TASK 2 – Finite Element Analysis

In this task, finite element analysis will be employed to model a number of the scenarios developed in Task 1. This will enable a number of liner / host main combinations to be investigated.

TASK 3 – Design of Electrofusion Parameters for SDR 33 and SDR 51 Pipe

Perform a series of tests to prove the feasibility of welding high SDR PE100 materials. The work will design an electrofusion procedure for joining low wall thickness (SDR 33 and SDR 51) pipe using electro fusion couplers. TASK 4 – Purchase PE Pipe

Purchase of PE100 pipe and associated fittings in order to perform the buckling tests. These tests will be performed on pipe of 315 mm or 355 mm diameter (depending on availability).

TASK 5 – Buckling Tests

Perform a trial to assess the required external pressure to collapse thin wall PE100 (SDR 33 and 51). Further testing will be done to characterise the resistance to buckling when exposed to external pressure.

Objectives:

To identify and develop solutions to issues that might limit the introduction and operation of polymeric pipes, with a much lower wall thickness than those currently supplied to GIS specifications, for use as liners within CI pipes.  At large diameters, PE pipes to GIS specification consume a large quantity of material. For the refurbishment of large iron pipes (tiers 2 and 3), it is believed that linings fabricated at reduced wall thickness can be made entirely fit for purpose with a consequent improved economics of material consumption. The objective of this project would be to identify and indicate engineering solutions to issues that might limit pipeline construction procedures or long term performance of pipe with revised dimensions.

Expected Benefits: Success of this project would be the ability to provide planning and installation engineers with proposals for a revised plastic pipe technology that makes far more efficient usage of resources, whilst maintaining the proven advantages of all-welded PE pipe construction.