If it were a spectacle blind you would rotate it when the blank was removed. Hence the dimensions and loads on piping remain neutral. Suggest you insert a spacer for the removed temporary strainer unless you are absolutely sure that no additional loads will be applied to the equipment.
Company practices may dictate what you should do. If you are a contractor and the specification has woolly clauses like "to good engineering practice" then there will be a dispute but the risk does pass to the contractor.
Not a good idea to leave temporary strainers in place as they are generally made from carbon steel and will rust in time. Not much attention is paid to the welding of them. They are difficult to clean if they actually trap anything.
I have seen them collect everything including nuts and bolts, welding rods, chocks of wood etc. Its amazing that during construction how handy that hole (the end of an uncompleted pipe) is for temporarily placing an item that you then forget where you have put it!
Geoff Stone
elie altawil <eliealtawil@yahoo.com> wrote: Your scenario works only in a perfect world. After 3 months in service, you may find out that the gap between flanges became wider or closer than you think. If you have a elbow close by, 6 mm on a 12" line may not be an issue.
Idealy, you should plan to replace the screen with a spacer.
Replacing a start up screen depends on the quality of fluid and construction. You should periodically monitor pressure drop across the screen. We typically remove the screen after 6 months of continous flow.
On a project I completed last year, the screen stopped up after only 24 hour of service due to failure of the pipeline's intenal FBE lining.
This is just my humble opinion.
>
>
>
>
> Hello everybody
> Temporary strainers are specified on piping
> connected to pumps and compressors during
> commissioning.They are placed between two flanges,
> so there is a gasket specified on both sides of the
> strainer.If the thickness of the strainer plate is
> 't' mm , then the total space between the two
> flanges is (6 + t )mm .(taking gasket thickness =
> 3mm ).The same is reflected on the isometrics.
>
> Now , after commissioning , when this strainer is
> removed , how is the gap created by removal of the
> strainer ( 3+t )mm compensated for ?
>
> Is a spacer ring of thickness 't' installed in
> place of the strainer.? If this is not the case ,
> then strain is being imposed on the equipment nozzle
> for which there is no accounting during stress
> analysis.
>
> Regards,
>
>
>
>
>
>
> ---------------------------------
> Free antispam, antivirus and 1GB to save all your
> messages
> Only in Yahoo! Mail: http://in.mail.yahoo.com
>
> [Non-text portions of this message have been
> removed]
>
>
To unsubscribe from this group, send an email to: PipingDesign-unsubscribe@yahoogroups.com
Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Design Detail and Development (a division of Blenray Pty Ltd)
Mail Address PO Box 1351 Castle Hill NSW 1765 Australia Tel Mob 0402 35 2313
Office 02 8850 2313 AH 02 8850 2324
We specialise in pipe network and waterhammer analysis, pipe stress analysis,
the design of buried pipelines and thermoplastic pipe systems.
[Non-text portions of this message have been removed] Received on Tue Aug 30 18:22:00 2005
This archive was generated by hypermail 2.1.8 : Mon Oct 27 2008 - 20:24:08 EDT