Ductile Iron Pumping Main - Joint Type

[IKsy]

Is it commonly acceptable to use ductile iron pipes with push-on spigot/ socket type joints for pumping main where the design internal pressure is in the region of 10 to 15 bars?

My apologies if the question had been raised previously. I couldn't find any direct answer in this forum.

 

[europipe]

Is there info from the vendor of that connection system,
I think they have design conditions for that.

 

[LittleInch]

See e.g.

http://www.hambaker.co.uk/docs/DuctilePipes.pdf

I'm actually quite surprised at the pressure rating of these units and pipes (>= 16 barg), but of course the key issue is making sure that they don't push out at bends or fittings, hence lots of concrete blocks...

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[SteveWag]

Actually that is very common, 15 bar is about 220 PSI. In the US we commonly use 300 PSI rated DIP and fittings, and that’s working pressure. Some sort of joint restraint is required. That type of fitting is almost never used above ground. Restraint is only required at valves and bends made with fittings. Deflection at joints is limited and doesn’t require much attention. Concrete thrust blocks are OK, but restrained joints and buried pipe lengths seem better. See this for a calculator:

http://rcp.ebaa.com/

Steve

 

[Drazen]

i actually don't know about other type of joint, flange joint is not acceptable for bellow ground installation.

as previous post stated, reinforcements are needed on critical points - bends, tees. manufacturers of pipes give detailed requirements for concrete blocks.

 

[IKsy]

Thank you all for your replies and also the useful links. But Drazen, may I know why it is not acceptable to use flanged joints for below ground installation?

 

[IKsy]

Perhaps there is concern that the flanged joints for buried pipeline may fail in the event of excessive settlement and vibration, considering the rigid nature of the joints?