Dear All,
Can I have experts’ advice on following issue?

I have analyzed a water injection system from header to X-mas nozzle for a offshore jacketed platform. I have considered a pressure unbalanced force (90KN,occasional, DLF =1.6)) at 6" NB dump valve which allows almost 42 barg pressure drop across it ( inlet header ope. pressure 42 barg and outlet is open to Atm to overboard drain). I have got information from our C&A team about the % (100%) of opening and actual throat area (130mm). Due to the space limitation and unavailability of structure, I need to install the valve horizontally (outlet is downward) with axial stop support at horizontal inlet line.

But Vendor is opposing to change the actuator in horizontal and asking for basis of force calculation. per vendor, the flow path through Lincolnlog is torturous and Fluid energy will be dissipated when flowing through the trim. So, this formula alone is not sufficient to reflect the real scenario inside the trim.

Inclusion of this force is a safety concern when, the valve opens suddenly (manual operation).I did not considerd any momentum force even. Only static force for pressure unbalance has been considerd as delta-P x throttle Area x DLF.

My questions are:
1) Is this a general practice to consider thrust force at Dump valve like pressure safety valve? or I can ignore assuming that there will be a slow opening ( no mistake) for blow down.
2) Is this impractical to install the dump valve as horizontal? As i have requested vendor to check support requirement on horizontal Actuator (1300 mm long).

Dear All,
I have been waited for long time to get some light from you. Anyway ,I got some information on Energy institute Guideline to calculate the forces for quick opening of shutdown valves as shared below....

Multiphase mass flowrate (W) in Kg/s,
Specific heat ratio (g),
Gas constant ( R) in K/K.mol,
Molecular weight (Mw) in g/mol
Upstream Temperature (Te) in K
Static pressure drop (dP) in Pa
Multiphase density ( r ) in Kg/m3
As per Energy Institute Guideline, Technical Module-02 (TM2)
Peak force (Fmax) in kN
For Dry gas valve opening..(W/1000)* SQRT[2*g*R*Te/(g+1)*Mw]
ForLiquide/multiphase valve opening.... (W/1.58)x SQRT[(dP.10-5)/r]
Likehood of failure (LOF) Calculation........
Dext= Pipe outer diameter in mm
Dint = Pipe internal diameter in mm
y = Actual pipe wall thickness/Schedule 40 pipe wall thickness
"Achieved minimum fundamental natural frequency based on software simulation in Hz"= f (this will give you type of support arrangement and correction value from Table T2-1 and T2-4
Correction factor (q)
Limit force (Flim) in kN
(16.8*y3-1.81*y2+525*y+25.3)*Dext*q*п*Dint2/(4*109)
Likehood of Failure (LOF)= Fmax/Flim
If LOF is less than 1.0, susceptibility of fatigue failure due to flow induced vibration (FIV) can be treated as 'Negligible', Otherwise ....
Study the recomended guideline....best of luck.