To M. Moleshi,
The loads on the equipment need to be compared for the sustained (cold) case and for the operating (hot) case. If the loads in cold case are low, but loads for the hot operating case are high, then spring supports might be one solution to deal with the piping expansion and equipment thermal displacements. Another apporoach to dealing with piping expansion is to locate vertical support, guide, limit stop, and / or anchor to control expansion movement to directions away from the equipment. Any gaps used in guide or limit stops should be evaluated against the un-restrained thermal expansion - the selected gaps could have little effect unless the gaps are large enough to allow sufficient movement, or if the gaps result in not enough retraint to control loads. If the cold sustained case loads are in excess of the allowable loads, then the supports and possibly piping geometry first need to be improved to reduce the loads on equipment. The directions of the high operating loads will indicate which directions need more flexibility to absorb thermal expansion. If the allowable loads are very small such that it is difficult to achieve acceptable operating loads by improved supports design, then one last tool to use would be cold spring of the piping by use of 'cut short' or 'cut long' elements in those directions of high loads.
Heat exchangers and rotating equipment can have ridiculous low allowable loads, so some negotiation with vendors is often needed to arrive at allowable loads and piping compliance. The API 610 pump packge supplied by one vendor had option for reinforced baseplate to increase the allowable loads to 2x the API 610 allowable. The cost increase of slightly more than 1% of the pumps package was worth the savings from the simplified piping. How could a vendor propose a baseplate too weak to even sustain the low allowable loads of API 610 !
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R Yee
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