DI Pipe Differeneces

The K ratings are ratings for pipe specs, the IS rating is standards for pipe usage...I think

IS 8329 is Indian Standard Code for DI pipes, where K is a whole number used for thickness class designation. i.e.. DI K9 pipes has more thickness and handle more pressure than DI K7 Pipes.

The Thickness and pressure handling capacity of DI K7 is less than DI K9 Pipes for pipes of Dia 80 mm to 1000 mm, but its same for pipes of Dia 1100mm to 2000mm

Regards

Linesh Chungath

India

I am not sure, but IMHO

If you look at the formulae in clause 4.3

Wall thickness e = K (0.05+0.001DN)

You will see that

1- The wall thickness (table 2) is more than the K9 for the common wall thickness (K7,K8,K9)

2- The table at 4.5 makes the K series common for large sizes at PN10, 16 and 25 (only PN40 is higher rated)

3- The hydrostatic requirement at clause 11 and table 1 are different for different K Nos (though I suspect that K7 would clear the K9 value)

It is my interpretation from the standard (and might be wrong)

If you see Table 2 the thickness of K7 & K8 Pipes are not matching to the wall thickness formula and the thickness of pipes from 1100mm dia to 2000mm dia for class K7,K8, K9 are the same and even in a manufacturer's site i have seen the same wall thickness for 1200mm dia K7 & K9 Pipe

For Pressure rating Refer Annex E _ Last page of IS 8329: 2000 where AOP is the same from 1100mm dia to 2000mm dia class K7,K8,K9 Pipes

Linesh Chungath