Hi!!!

I am little bit confused about this 'SUS Pull' term. Many of my friends suggest me that if you are using spring support near nozzle then you should check the vertical displacement (Sustained Pull) of spring for SUS case. It should not be more than 3 mm else it would be difficult for alignment purpose after the dismantling work.
My question is that if the SUS pull is 10 mm and the nozzle is passed in SUS and OPE case (both in stresses and loads consideration) then is it required to check such type of 'SUS Pull'? (though, at the time of desmantling work the spring is locked)
I have also checked the displacements and stresses in WNC case and these are within the allowable.
Please guide.

As per good engineering practice the check is must especially if near sensitive equipments like pumps,compressors & turbines where an accurate alignment is required. The Spring must be restricted to 1mm, although your nozzle loads pass & safe in WNC still better to restrict it to 1mm.In such case why don't u try playing with operating load ranges & restrict the sus-spring movement. As good engg. practice, In such case on isometrics or spring specification you can put a note: Spring to be locked before maintenace,

You need to consider also the fact that the pin removal will be difficult to be done if your spring hanger is not in balance with the pipe weight.

Regards,