Re: installation of control valve & instument

straight length thumb rule for flow instruments is 10D upstream & 5D downstream, I always follow 14D upstream and 3.5 downstream, process final dimensions generally in between this. this is safer. control valve don't need straight length, after control station give spool for flow element.

Amit Vedak
Piping Designer, UAE

• In PipingDesign@yahoogroups.com, "chm_mech" <chm_mech@...> wrote:
  >
  > Hi,
  > I would like to know what is the thumb rule to decide min
  > straight length of the pipe for installing a control valve &
  instrument
  >
  > Thanks for enough in advance
  >