A good day to all,

I just want to inquire, it is a good practice to put a hanger or spring can support in piping around pump? Because of a very low flexibility of the piping configuration the load exceed the pump nozzle allowable, so i try to replace stachion support by hanger support then the result is lower than the allowable.

thank you in advance

regards,

junmar

Installation of a spring or hanger is a very common practice to solve pump nozzle loading challenges. IMO "good practice" is to have a design that doesn't require them, but often that is not possible. NB a spring installed incorrectly can make nozzle loading worse no matter how good your analysis is, but that could also be true for a well designed system w/o springs.

Mabuhay!



The more springs are to be added/used in the piping system, the more it became unstable against wind, seismic and other external load. Thus, it is preferable not to use springs/hangers as much as possile.

Here are some tips when to use springs/hangers.

a. When piping system lifts up due to thermal in W+P+T and Y-stop supports or equipment nozzle couldn't support large piping weight. Even if the piping system lifts up in load case W+P+T, spring need not be used unless calculated stress exceeds allowable stress in load case W+P

b. When the rigid support can't deal with the large movement of piping near equipment nozzle.

In short, if you have a large displacement and large force that couldn't be dealt with rigid type of supports, think of springs/hangers as an option but not yet as solution,... because there might be another way to solve your problem without using a costly spring/hanger.





Stress analysis? read, ask, understand and apply.

I read this many times in this forum... If you have spring in your calculation then it must be seen in the construction.(i forgot the exact statement)

Stanchion in my understanding are not reliable in front of pump if your surrounding temp reaching to -ve low where +ve installation. Why? during cold season this thing shrink and may give additional problem. While spring can absorb vertical displacements. Most pump cases are hard to justify without spring support. And I believe that is the most important thing to do. "GET IT PASSED"

Regards,

Kuyaw ka!!


This is the very most common problems when analyzing pumps.
We encounter these many times until the point we cannot think anymore
of ways reducing the nozzle loads. Now, we are trying to use expansion joint. Is this advisable?



Regards,
Machoguy.

Expansion joints are the easy way out based on the assumption you understand the correct way to design an expansion joint. With that said, an expansion joint adds a consumable to your system, i.e. maintenance and inspection costs that did not exist without one. The decision to use an expansion joint should not be frivolous.

Kumusta & Mabuhay!

For rotating equipments where alignment is necessary (i.e. end-suction pumps), we usually use adjustable base support. We can use rigid or spring can support whichever is necessary to minimize force and moment loads.

Though for use of spring can on two parallel pumps where one is standby and one is operational, take note that during pump shut-down the pipe does not have fluid weight, the spring load design in this case would tend to push the pipe upwards creating vertical forces and bending moments. This case should be considered on your analysis.

For expansion joints, yes this is acceptable. But, carefull consideration of thrust load should be observed. A tie-rod is the most common that can allow a limited lateral movements depending on the design, but this wont help your axial loads. If you want to minimize your axial load, dont put tie-rods, instead put an anchor support downstream of the EJ, and dont forget to give the load to your civil/structural group on the anchor support, and inform the pump vendor.

Goodluck!