NO PRV ON 384 FEET VERTICAL COPPER PIPE

[moideen]

70 story residential building, water pumping from basement to 31st floor then pumped to 60th floor. The water tank placed on 31st floor and 60th floor. a VFD booster pump maintains the pressure above the 60th floors. The issues are the water leakage broadly mainly on joints. this is 10-year-old building. the leakage happening on before the branch PRV, the PRV has not seen on main pipe. Only installed on branch pipes. The pipe copper with code of BS-2871-table-X. my question, is that design mistake without installing PRV on main pipe. 31st floor to basement around 384 feet. Then pressure will be exerted 384/2.31=166 psig (26 bar). Is it design error??
thanks

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[MJCronin]

Who made the design drawings for this mess ??? n..... Why are they not taking responsibility for their work ?

Did you ask the Architect of Record why HIS water system doesn't work ?

Ask him also if he collected his FULL FEE for the project ??

MJCronin
Sr. Process Engineer

 

[LittleInch]

I'm struggling to follow the diagram or where your PRVs are. Are you saying that each floor has a PRV fed off a long vertical pipe down from the tanks?

Your calcualtion is correct up to 166 psig, but this is 11. bar, not 25.

I don't know what the pressure rating of that pipe or fittings are - can you tell us? A google search say 17 bar for 108mm, so OK to me.

I think you would normally see a stepped pressure range from the main header or the header designed for the pressure.

Would appear your issue is with the installation standard of the joints....



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[moideen]

LittleInch :yes, it is 11 bar.having error so i deleted the hand sketch,i mean prv not fitted in 17 meter vertical head. prv fitted on branch pipe which take off from main header.the drawing says the pipe standard BS-2871-table-X. some says that replace copper with PPR. will withstand the PPR 11 bar or good practice to using PPR in high pressure line.

 

[LittleInch]

So long as you buy PN 12.5 or PN 16 or 20 pipe then you should be OK.

If you state the required pressure to the suppliers then they will give you the right material.

How well it gets put together has a much higher impact on performance...

PPR looks ok but I've no experience. You might be better off asking in the water treatment and distribution forum about the specific of PPR vs copper

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[moideen]

LittleInch :thank you, i prepared my retrofit scope with PPR pn20, brand hepworth. the current copper thickness 1.2 mm and mainly leaks on joints. so i think the flushing work was may be not good at commissioning time.