The four ISO systems Standards, ISO 11296-11299 cover plastic pipes in renovation of gravity sewerage, pressure sewerage, water and gas supply respectively. Each requires that an installation manual be provided by the installer of the plastic pipe.
Clause 9.4.1 Installation: requires that the installer provide an installation manual detailing all the procedures to be carried out during installation and specifying all key process parameters together with relevant values and tolerances. It also requires that the installer carry out the works with a competent well trained team conversant with the installation manual.
Clause 9.5 Process-related inspection and testing: requires that the manual specifies the required measurements and other tests relating to the installation process that must be recorded during installation, and that all such measurements are documented in the manual, thus providing a sound basis upon which QA inspections can be carried out on site.
Clause 9.7 Reconnection to the existing pipeline: recognising that the client’s operational team will not have the same expertise, nor the same special equipment and training, this requires the installer to include in the installation manual details of all the procedures to be carried out during maintenance and operation, including emergency procedures for dealing with mechanical damage and bursts, special equipment and training required, and what spare fittings etc. should be available.
This manual provides the client with a good opportunity to assess the installer’s proposal. All of the following parameters which are applicable should be provided:
- Proposed insertion technique
- Host pipe internal diameter assumptions
- Chosen PE100 liner pipe diameter
- Chosen PE100 liner pipe material and SDR
- Insertion temperature assumptions
- Proposed diameter reduction (if applicable)
- Range of actual host pipe internal diameters that can be accommodated
- Master (and slave(s) if provided) die throat diameters for Die Drawing
- Roller module throat diameter(s) for TiteLiner
- Roller module throat diameter(s) for Rolldown
- Predicted running diameter(s) for all reduction options
- Insertion length
- Insertion load(s) – winch load and load on PE100 pipe
- Maximum permitted load
- Anticipated longitudinal extension and required length of liner pipe in die drawing
- Time to achieve tight fit for all reduction options
- Hydraulic reversion pressure for Rolldown and for Fold and Form methods
- Type and dimensions of termination fittings to be used
- Final ‘free’ internal and external diameters of the liner for termination fitting design
The manual should include tolerances on certain parameters because they may be subject to change if the host pipe diameter assumptions are not accurate, or the insertion temperature is different from the assumption made.
Because the actual internal diameter of the host pipe is difficult to determine accurately in advance, and because it has been found that the internal diameter can very from pipe length to pipe length, the installer’s proposal should be flexible enough to accommodate reasonable variations and still achieve a close or tight fit as appropriate when the close-fit methods are used. For concentric reduction methods this means choosing a liner diameter in excess of the largest assumed host internal diameter, and providing a range of reduction options to accommodate the smallest assumed host internal diameter. For folded methods it means choosing the liner diameter smaller than the smallest assumed host internal diameter in order that full reversion can take place. The running diameter and the running load should be provided for each reduction option.
Dimensional parameters need to be given to the manufacturer of the liner termination fittings, and should be carefully checked as these fittings are expensive and may have a lead time of several weeks.