Flow induced vibration on piping downstream of PSV

[chatrik]

We have problem with our existing piping downstream of PSVs in our gas production platform. Result from process calculation shows that the blowdown downstream velocity is too high, ie. Mach No. is greater than 0.7 and ñv2 is greater than 150,000 kg/m/sec2. Are there any software to be used to simulate the vibration induced from the blowdown of these PSVs or are there any engineering company who perform this type of work, especially in piping flow induced vibration.
Thank you very much for any informations.
Best Regards,
Chatri K.

 

[mfontenot29]

Hello Chatri,

Computational Fluid Dynamics (CFD) software is now mature enough to estimate turbulence kinetic energy and frequencies through a PSV which can be translated into fluctuating pressures/velocities and frequencies.

That information can then be used as loads in a Finite Element Analysis (FEA) program for analysis. FEA programs can model shells for the most important part of the piping immediately downstream and then transition to beam elements further away. Also, some of the more sophisticated FEA packages allow for random loads.

I would be interested to know if anyone else responded to this tough problem with a different answer.

Mike

 

[SPLIT]

I have solver many pipe vibrations problems due of autoinduced control valves vibrations.

It is important to check the control valve, because when it is operating in a choked or cavitating conditions, it generates a lot of vibration.In many cases , we were forced to change the valve, when previously check was concluded that operated at choked or cavitating conditions.


Regards,


SPLIT

 

[T5580]

Chatrik,
Suggest you can get the following papers:
- Failure of Safety Valves due to Flow-Induced Vibration by J.T.Coffman; Oklahoma Gas and Electric Co. & M.D.Bernstein; Foster Wheeler Energy Corporation.
- Control of Flow-Induced Vibration in Safety Relief Valves by H.RSimmons, Sr. Research Center Engineer & R.M. Baldwin, Sr. Research Center Engineer; Southwest Research Institute. San Antonio, Texas.
I hope this helps.
Regards,

 

[hacksaw]

PSV piping design and associated pipe stress analysis should be routine for most engineering firms. Most piping analysis codes include provisions estimating pipe dynamics for your given supports and bracing.

The valve and piping support are critical especially for pilot operated valves.