HI

i would like to ask a few questions regarding pump discharge piping

iam doing Pump discharge piping system for cooling water temperature of 60 deg,tied expansion joint is provided at the pump discharge.

my first support is spring hanger on each lug of the pump discharge.but variation of the spring is just 2% only.If i replace the spring hanger with rigid support +Z(vertically Up)in operating case the load on the support is zero as pipe is lifting ".25mm" and complete vertical load is acting on the nozzle as first support is useless

Here is my question

Theoretically:- caesar is calculating the load on the support is based on displacement acting on that node,even if the support is lifting ".01 mm" the load on the support is zero

Practically: such a small gap will fill up the pipe itself by yielding and it will seated on the support properly, and we can avoid the use of spring with help of practical judgement by neglecting the ceasr result

Please correct me if iam wrong

in my case due to some space constraints rigid hanger is the only one option that i can use instead of spring, when change it the load on rigid support is compressive load

please advice me if i proceed with rigid hanger.


Thanks in advance

here is snapshot

What's the line size?

I have some serious apprehensions about the use of bellow for cooling water line running at 32 deg C.

Because I had seen some serious disasters at site for such cooling water systems with bellow!!

Going by the picture, I guess the line size is 20".

Hi Mr Sj

the line size is 16" which is connected to header of 20"
and the line temperature is 60 deg

Expansion joint is specific requirement of client at pump nozzle

Does the hold down in the header see positive load in Y? If yes, remove them!!

There is no positive load in the header support, to avoid iteration error provided Z instead of +z

i would like to ask you that have your ever gone through such system (less critical) where u have implemented your practical judgement(Neglecting caesar results) to avoid some exotic supporting.

Yes.

In fact it was a big cooling tower pump discharge line!!

As you know at ope temp of 32 deg C, there is hardly any movement & therefore, we avoided the bellow in the discharge side.

By the way, you can ignore this 0.25 mm movement.

Alternatively, you may design your spring to carry all of the load in vertical direction by using "free restraint at node" option.

I see that you've applied stiffnesses at pump nozzle?Is it so?

Thank you so much for your quick responds


it would be really interesting if other can also share their experience in their engineering life like,some times our decision more practical oriented rather than gong after a programmed software results.
this will be more help full for me as well as other forum members.