A guide and axial limit stop at nodes 45 and 105 produces little increase in thermal stresses, which were low to begin with, and serves to attenuate the large axial displacements in the line due to the water hammer load. Loads on this support due to the low mode displacements are seen to be small. Local, very short duration loads may not be so small. The restraint should be designed with this in mind.
A few simple design rules are usually sufficient:
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Flexible is optimal. The restraint should only be stiff enough to sufficiently attenuate the low frequency gross deformation.
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Areas of local discontinuities, such as the weld of the support to the pipe, should have extra weld or support plate area. Discontinuities at other restraints in a problem area should also be reinforced to withstand the local passing of the impact stress wave.
