ISO/TS 10986:2021 Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes — System design of above ground pipe and joint installations without end thrust.
4.4.5 Adjusting joints The joint should be adjusted if any of the checks described in the preceding clauses fall outside the specified limits. The necessary adjustments of coupling or pipe position should be made carefully, avoiding concentrated loads or impact loads that can damage the pipe or the coupling.
5 Installation of above ground pipes 5.1 General The designer of an above ground pipe installation should be aware of the forces that act on the pipe system, particularly where high system pressures exist. When a component in a pressurized pipeline has a change in cross-sectional area or alignment direction, a resultant force is induced. All components such as bends, reducers, tees, wyes or valves shall be anchored or restrained to withstand these loads. This is the case for above ground as well as buried pipes. In buried pipelines, adequate resistance to movements at joints in undeflected installations is generally provided by the pipe embedment. Such resistance shall be provided at the supports of an above ground pipeline. Care shall be exercised to minimize misalignments and all components shall be properly supported to ensure the stability of the pipeline.
5.2 Supporting of pipes 5.2.1 General A range of joint designs are manufactured for which a variety of support configurations are recommended. Generally, pipes are supported on either side of the joint, but some systems allow direct support under the joint. To minimize the loads induced in pipes and supports, the supports should not restrain longitudinal expansion of the pipes. However, it is essential that the pipe movements be guided and controlled in such a way that all pipe sections are stable and that acceptable longitudinal movement of the pipe in the couplings is not exceeded. As non-restrained couplings are flexible, it is very important for the stability of every pipe component to be ensured by the supports. Each pipe should therefore be supported by at least two cradles and anchored by a pipe anchor at one of these cradles, while the remaining cradles should be designed as guides, allowing longitudinal expansion of the pipe but restraining lateral movements. With direct support under the joints, the coupling clamp can act as anchor, see Figure 6 (1) and Figure 8. For pipes supported in more than two cradles, the cradle closest to the middle of the pipe should be used as an anchor. The anchors should be located with regular spacing to ensure even distribution of longitudinal pipe expansion on the joints. However, the maximum distance between two anchors shall not result in exceeding the draw limits specified for the joint given in ISO 23856. Figure 6 shows typical support arrangements for pipes.
ISO/TS 10986 pdf download.