agreed. i was just responding to the last posting. wouldnt a knife-edge be a better choice instead of a solid bars (well actually both are bad choices to control frictional load).
geotechnical survey carried indicated rusting of the rebar attirbuted to the presence of high chloride. Rebar vol. increases due to rusting resulting in conc. spalling. forensic study also indicated possible use of water with high cholirde during mixing of concrete and some sacrifical anodes are not providing the necessary protection. Part of the survey also indicated water runoff resulting in the sleeper to sink. in our case, about 300 nos. of sleepers were affected. the conc. remediation program addresses both repair/replacement.
-----Original Message-----
From: SubrataP_Saha@ril.com [mailto:SubrataP_Saha@ril.com]
Sent: 04 May, 2002 9:57 AM
To: PipingDesign@yahoogroups.com
Subject: RE: [PipingDesign] Piping Queries - II
sliding type support are commercially available and part of the support configuration per MSS.
It is true that supports for reduction of friction component are commercially available. However the posting wanted to know about the utility of the rod on the sleeper. This sleeper design is a generic one and used by many consultants and exist in several refineries. The simple advantages are reduced friction and corrosion at a low cost.
the problem actually is the sleeper itself. we're now spending million of riyals to rehab the concrete sleepers. its showing signs of cracking, sinking and spalling. lost the sleeper, then pipeline is airborne.
What reasons do attribute to the loss of sleepers referred above ?
"SARE, RALPH H." <SARERH@YANPET.SABIC.com> on 05/04/2002 11:01:08 AM
Please respond to PipingDesign@yahoogroups.com
To: "'PipingDesign@yahoogroups.com'" <PipingDesign@yahoogroups.com>
cc:
Subject: RE: [PipingDesign] Piping Queries - II
sliding type support are commercially available and part of the support
configuration per MSS. the snubbers, saddle, steel support structure and
the
spring cans cost more (much more). you only provide this type of support
where its needed (therefore its cost is justified) and not in every
sleepers
along the pipeline. if the line can accomodate the movement and there is no
need to control the frictional load then o bviuolsy one does not need to
install it.
the problem actually is the sleeper itself. we're now spending million of riyals to rehab the concrete sleepers. its showing signs of cracking, sinking and spalling. lost the sleeper, then pipeline is airborne.
-----Original Message-----
From: SubrataP_Saha@ril.com [mailto:SubrataP_Saha@ril.com]
Obviously due cost implications
and inconvenience of maintenance teflon / rollers are prohibitive. Just
imagine kilometers of pipe in offsites to be mounted on rollers or PTFE .
We have never witnessed any problems in the sleepers so far.
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Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ Received on Sat May 04 06:20:00 2002
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