Flow rate calculation

[layloban]

Hi,

I have a question about flow rate calculation. The situation is that there is a 150# process drain with 1" diameter. We have been told to install a reducer to decrease the pipe diameter to 1/2" first before it goes into a drain tank. The reason is to reduce the pressure such that whhen the drain valve (1&quot is open the water will not splash into the tank as much.

I would have thought that reducing the diameter of the pipe will introduce the pressure drop, however, because the dia. is reduced, the velocity of the fluid will increase. Thus the water going into the drain tank will splash even worse.

Please advise. I appreciate your help in advance.

 

[CRG]

Pressure at the outlet of the process drain will be the same as the drain tank. This is independent of the pipe size. You are correct in your concern for the velocity of the entering fluid. It is the fluid velocity and orientation of the drain entering the tank that will create the splashing. If you want the velocity to be minimized, increase the pipe size before entering the tank or install a flow restriction device (orifice, globe valve, etc.) in the line. If you described the pipe layout, a recommendation could be made as to the best place to change pipe size or install flow restriction device.

CRG

 

[quark]

You are right. There will be more problems if you increase the velocity. Why can't you dip the pipe in?

Regards,

 

[layloban]

Thank you very much!