1 reply to this topic

[drdave]

Hello,

Higher capacity cooling tower pumps are normally equipped with motor operated discharge valves to avoid manual turmoil / hassle & unnecessary delay of operation / isolation.
such MOVs are mounted in front of Cooling tower pumps.

Can these be extended on DCS panel in parallel to local operation to initiate actions faster?
Is there any process safety criterias to have MOV for big machineries within certain distance of operation?????
Thanks
Dave

[sgkim]

Hi Dave,

Block valves for large size liquid piping or pumps shall be closed slowly to avoid instantenous building up of pressure at the valve due to the kinetic energy of the flow it is blocked quickly. MOV is used for this purpose - to intentionally delay the closing speed of the line. Quick action is to be avoided. Rather, the operation of the MOV is preferably be done by the manual switch provided locally.

Stefano/050801