Re: [Man.Distr]Re: Swing Check Valve

From: <elie>
Date: Tue Sep 13 2005 - 08:49:00 EDT

Here, in service means replacing the flapper without taking removing the check valve. You still have to blowdown/purge the line from pressure.

• tomcruz55 <tomcruz55@yahoo.com> wrote:

> Is this similar to a double block and bleed
> arrangement? or is it
> similar to the arrangement in the PSV?
>
>
> --- In PipingDesign@yahoogroups.com, "Paul Bowers"
> <pbowers@p...>
> wrote:
> > I think to do an in-service internals replacement
> you'd need a
> duplex setup
> > such as I've seen with metered city water supply
> systems, but my
> memory is
> > fuzzy on this. It looks like there might be a spec
>
> misunderstanding or
> > confusing writing as Steve suggests.
> >
> > Paul
> >
> >
> > ----- Original Message -----
> > From: "Steve McKenzie" <mechproj@x...>
> > To: <PipingDesign@yahoogroups.com>
> > Sent: Wednesday, January 07, 2004 5:18 AM
> > Subject: RE: [Man.Distr]Re: [PipingDesign] Swing
> Check Valve
> >
> >
> > > Hi Sajit
> > >
> > > I have never seen a swing check that permits "in
> service swing
> > replacement",
> > > and I doubt if there is any such thing as it
> would need two
> additional
> > > sealing arrangements (valves) plus body drain.
> Perhaps the spec
> writer
> > means
> > > "in-line disc and body seat replacement"; i.e.
> it is not
> necessary to
> > remove
> > > the valve from the pipeline in order to replace
> the
> sealing/wearing
> > > components. Also I am not aware of any part of a
> swing check
> valve called
> > a
> > > swing. You may wish to query this with the spec
> writer.
> > >
> > > A note of caution; most swing checks have a
> hinge pin that is
> removed from
> > > the side of the body. Side clearance is required
> to remove the
> spindle,
> > > otherwise the body may need to be removed from
> the pipeline.
> > >
> > > Cheers
> > >
> > > Steve McKenzie
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: Sajit Viswan [mailto:sviswan@t...]
> > > Sent: Wednesday, January 07, 2004 6:59 PM
> > > To: <a href="/group/PipingDesign/post?postID=KEEcafCdELydzjqx29aW_548ptkKnTwdbCU83UDb6u_gEVkAMYYc7S-o8TZ0KNuWrT8f_fv652pvmQ3oFV0cV269">PipingDesign@yahoogroups.com</a>
> > > Subject: RE: [Man.Distr]Re: [PipingDesign] Swing
> Check Valve
> > >
> > >
> > > The PID calls for this requirement. "Full bore
> check valve with
> external
> > arm
> > > shall be top entry and allow swing replacement
> in service". The
> line size
> > is
> > > 18". There are block valves shown across it with
> a drain d/s. I
> believe
> > that
> > > this does not imply that the block valves have
> to be closed and
> then the
> > > swing taken out for maintenance, which then is
> an ordinary check
> valve
> > with
> > > only an external arm or a dash-pot.
> > >
> > > Sajit
> > >
> > > -----Original Message-----
> > > From: rajendra bajikar
> [mailto:rajendrabajikar@y...]
> > > Sent: Wednesday, January 07, 2004 9:30 AM
> > > To: <a href="/group/PipingDesign/post?postID=KEEcafCdELydzjqx29aW_548ptkKnTwdbCU83UDb6u_gEVkAMYYc7S-o8TZ0KNuWrT8f_fv652pvmQ3oFV0cV269">PipingDesign@yahoogroups.com</a>
> > > Subject: [Man.Distr]Re: [PipingDesign] Swing
> Check Valve
> > >
> > >
> > > Dear Sajit,
> > > Is this a one time problem or regular? What is
> the line size?
> Could you
> > > please elaborate?
> > > Regards,
> > > Rajendra Bajikar.
> > >
> > > Sajit Viswan <sviswan@t...> wrote:
> > > Is there a check valve that allows swing
> replacement while in
> service?
>
>
>

---

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