>>If the structure has not been built, then use values established in the literature. A welded steel structure is going to have different damping parameters than a bolted steel structure or a concrete structure.

my design is a pipe that comes from the pump and is supported by metal structures:

>>Please show the tabular data that is PERMISSIBLE VIBRATION AMPLITUDE 60 microns. Is that a statement about the pump or the pipe?

this approval is for the pump, it is indicated in the documentation for these pumps.

Can i use displacement to apply 60 microns? without converting it to a function?

>>The pump specification might have a requirement on the maximum unbalance of the rotor calculated from the mass m of the rotor and the radius r of the center of mass from the rotational axis. You can calculate the force F amplitude as a function of rotor angular velocity w using the formula F = mr(w^2). 

There is no data on the pump yet, it has not yet been manufactured. But the customer wants to make a calculation. 60 microns is all there is from the boundary conditions.