I am a mechanical engineer at a large petrocehemical complex in Turkey. We are located on the seaside and we have decided to feed our fire water pipeline with sea water during an emergency such as lack of fresh water or very low fresh water pressure. In the project the suction line from sea to the main collector (serving three centrifugal pumps) is about 50m long. What kind of material is appropriate for the suction line? It will be full of sea water at all times. Is 316L OK? We do not want to have corrosion problem in the near future.
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Sea Water Service Pipeline, 316L? 2
- Thread starter mufasa1
- Start date
What about cement lined CS pipe? We used that for our SW firewater systems on offshore platforms for the larger piping. For the smaller piping, we used some much more exotic alloy, a monel alloy if I remember correctly but that was 10+ years ago.
With 316L, my first question would be wrt stress corrosion cracking due to the chlorides in sea water.
With 316L, my first question would be wrt stress corrosion cracking due to the chlorides in sea water.
Suggest you use ABS as there are many locations in Australia & SE Asia where this material is used. Checkout The company is owned by Tyco and is represented throughout the world. Pipe is avaliable up to 1000mm diameter.
I have installed many systems for use on sea water, sewage sludge, potable water etc.
No fear of stress corrosion cracking
Standards are available from Look for AS 3518 & AS 3690. Check out the drafts as AS 3518 is under revision and you may be able to download for free.
I have installed many systems for use on sea water, sewage sludge, potable water etc.
No fear of stress corrosion cracking
Standards are available from Look for AS 3518 & AS 3690. Check out the drafts as AS 3518 is under revision and you may be able to download for free.
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1
- #5
for above ground application.
CS pipe EFW cement lined, coated and wrapped to awwa spec. downside is the maintenance. if the mortar lining comes loose then you will start seing and repairing leaks. at the valve-to-pipe joint, you will also expreince some flaking of the mortar lining requiring another repair/replacement. note that once you losse the cement lining its an uphill battle to just keep on monitoring the line and fixing it. OK in your case since lenght is only 50 m.
between 4-36 NPS we have started using CS pipe lined with fiberglass (glass flake such as those made by Jotun) reinforced vinyl ester resin. for the small branch connection, we have selected B43 brass annealed (too small to lined properly). so far the result is better thatn the cement lined cs pipe.
fiberglass. we have consider it (lcc is really very attractive) but decided againts it. reason - if it breaks, reparing the line is a struggle especially in a very tight area (ive been into one inside the valve pit wiht sea water ozzing out like a fountain).
ss pipe. some says that scc is a concern. well for scc to occur three things must be present - residual stress, excessive amount of chloride (well for seawater of course it must be excessive)and temperature (most of the documented failure related to scc has these properties). mode of failure is leak. there is no weld repair. either you shutdwon the system to repalce your spool or you install a clamp and assess the risk. beside its costly.
CS pipe EFW cement lined, coated and wrapped to awwa spec. downside is the maintenance. if the mortar lining comes loose then you will start seing and repairing leaks. at the valve-to-pipe joint, you will also expreince some flaking of the mortar lining requiring another repair/replacement. note that once you losse the cement lining its an uphill battle to just keep on monitoring the line and fixing it. OK in your case since lenght is only 50 m.
between 4-36 NPS we have started using CS pipe lined with fiberglass (glass flake such as those made by Jotun) reinforced vinyl ester resin. for the small branch connection, we have selected B43 brass annealed (too small to lined properly). so far the result is better thatn the cement lined cs pipe.
fiberglass. we have consider it (lcc is really very attractive) but decided againts it. reason - if it breaks, reparing the line is a struggle especially in a very tight area (ive been into one inside the valve pit wiht sea water ozzing out like a fountain).
ss pipe. some says that scc is a concern. well for scc to occur three things must be present - residual stress, excessive amount of chloride (well for seawater of course it must be excessive)and temperature (most of the documented failure related to scc has these properties). mode of failure is leak. there is no weld repair. either you shutdwon the system to repalce your spool or you install a clamp and assess the risk. beside its costly.
Stainless steel is not recommend for Seawater.You can use Fiberglass Reinforced Pies(GRP or RTRP).As an inert material ,fibergalss composite pipes have excellent anticorrosive properties.Seawater, chemicals, soil and atmospheric environments typical in severe corrosion within a short period of time.I've been good experience with GRP lines for seawater service in South Pars Gas Field (Iran)
In the North Sea offshore industry it is quite common to use 6MO stainless steels for Seawater service (wet firewater systems and water injection). Sometimes also titanium is used.
Some (10 or more) years ago Cunifer piping (=Cupro-Nickel) was the standard material for seawater, but nobody uses this anymore due to fabrication, installation and mechanical strength problems I think.
GRP is also used for seawater but normally only for "non-critical" systems, i.e. systems that is not required to work in case of emergency.
Maybe though for a large diameter onshore header it it is acceptable, and cheaper to use one of the other suggestions above.
Try the site or They have specs for SMO254
regards
Mogens
Some (10 or more) years ago Cunifer piping (=Cupro-Nickel) was the standard material for seawater, but nobody uses this anymore due to fabrication, installation and mechanical strength problems I think.
GRP is also used for seawater but normally only for "non-critical" systems, i.e. systems that is not required to work in case of emergency.
Maybe though for a large diameter onshore header it it is acceptable, and cheaper to use one of the other suggestions above.
Try the site or They have specs for SMO254
regards
Mogens
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1
- Thread starter
- #9
most common for seawater are ,,,FRP'S or C.S.cement lined
FRP'S potential problems are breakage...
cement lined c.s problems are when lining is gone...
a decision i beleive should be based on how good u will design and engineer any of the two options...
316 L ( known limit for the clorides part is 50 ppm ) ? seawater (thousands of chlorides ) ppms ?! no way !
cheers
- Thread starter
- #11
For your valves, go to Series 800, composite butterfly valve.
- Thread starter
- #16
George,
That is really an important issue if you are taking the water directly from the sea, lake etc. It is apparent that there will be clams and other settlements at the pipe intake. We think about using a self cleaning filter at the pipe intake. Lakos has such a filter up to 460m3/h for sea, lake and spring suctions. One idea was to keep the pipe out of the water at idle times with some kind of lever system which may not sound very practical..At the moment we do not have a clear solution. I will appreciate any idea on this matter..
That is really an important issue if you are taking the water directly from the sea, lake etc. It is apparent that there will be clams and other settlements at the pipe intake. We think about using a self cleaning filter at the pipe intake. Lakos has such a filter up to 460m3/h for sea, lake and spring suctions. One idea was to keep the pipe out of the water at idle times with some kind of lever system which may not sound very practical..At the moment we do not have a clear solution. I will appreciate any idea on this matter..
Dear Mufasa,
Just for your reference, In our power plant practise, we use GRP pipe for seawater intake DN2500 (undersea & underground). For aboveground, we use A53-B with rubberlinned. Rubber linning is an good option for seawater.
Regards
Kent
Just for your reference, In our power plant practise, we use GRP pipe for seawater intake DN2500 (undersea & underground). For aboveground, we use A53-B with rubberlinned. Rubber linning is an good option for seawater.
Regards
Kent
In one of the ammenity centre pipe 316L is leaking which is given for firefighting purpose.Can somebody suggest some material or other way like filling that portion with fresh water. Underground pipe is of GRP.Firewater pump discharge is of Duplex Stainless steel
Thanks
SA
Thanks
SA
tommyclose
Industrial
steel pipe cement mortar lined is suitable ,internationally accepted ,used and approved .....rgds TC
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