Issues regarding the quality of shimming installation for moving equipment.
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The specifications require that the height of the shim layer be 30–70 mm, with no more than five shims being used, and they should be placed as close as possible to the foot bolts. I have always wondered that when anchor bolts are tightened, they represent points under high stress. If the equipment base is sturdy enough to avoid deformation, then whether or not shims are placed away from the anchor bolts could be considered a violation of the requirements. Also, what effects can an excessive number and height of shims in the shim set have on the machine, and is it necessary to make corrections?
Why not follow the standards during construction? It’s very difficult to carry out repairs after the work is completed. If vibration levels are too high after testing, can you be sure whether it’s due to the equipment or to issues with the foundation construction? Once there are standards, one must follow them. If construction is not carried out in accordance with those standards, it’s only acceptable if you’re doing the work for yourself; no one else will agree that it’s fine or without problems.
When manufacturing the base of ordinary mechanical equipment, the area around the bolt holes is usually thickened or equipped with support beams, this being done to account for the tightening force exerted by the foundation bolts on the equipment base. Under normal conditions, the stress generated by vibrations in the equipment is greatest at the location of the foundation bolts; it is therefore best to follow the specifications and place shims on both sides of these bolts. The more shims there are, the smaller the average contact area of these shims becomes due to issues related to mechanical processing precision. The greater the total height of the shims, the poorer the stability of the shim set. It is necessary to follow the specifications to avoid disputes. It’s not that your approach will necessarily be problematic, but the underlying rationale for formulating standards is sound.