Site Jointing

It has long been recognised that the achilles heel of a thermoplastics pipe system 1s the quality of the site jointing procedure. Successful site welding, and indeed the making of mechanical joints, requires a higher level of competence than the more conventional jointing methods associated with traditional materials. This gap has recently taken a higher prominence as problem areas related to the materials themselves have been addressed.

A two-pronged solution has been proposed by the UK Water Industry. The first element 1s the establishment of a rigorous training, assessment, certification and licensing scheme for pipe jointers - with associated provision for trainers, assessors, supervisors and engineers. The second element is the concept of ‘joint ownership’ requiring the on-site marking of each joint by the jointer - a declaration of ownership by the competent and licensed jointer.

Progress on a proposed European Standard (1), which will apply to site welding of thermoplastics pipes, has added urgency to the task of developing the UK scheme. The Thermoplastics Jointing Group (TJG) has been established, supported by almost all the major UK water companies, to create and implement the industry’s proposals and at the same time

meet the requirements of the proposed Standard.
The TJG commenced work in January 1998. The deadlines for developing the proposals are tight - the timetable requires that the training scheme and the qualification & licensing framework will be in place and accredited by the end of 1998. Implementation will subsequently follow during 1999.
This Paper examines the background to the current proposals and the context within which they are perceived to be necessary. The work of the TJG is charted and a detailed vision of the implementation of the UK Water Industry scheme is set out. Once implemented, the quality gap will, at long last, be bridged and greater confidence in site jointing will be established.