[chart321]

Why is SDR 35 the preferred piping for gravity sewer applications? Its life span is less than HDPE piping? http://www.contractortalk.com/images/forums/smilies/sad.gif

 

[dayexco]

what trade is "CM"?

 

[dayexco]

heavier, harder to lay, harder to maneuver on job sites, (can't imagine it'd be too easy to throw a 20' stick of 8" HDPE over your shoulder and walk away with it like you can PVC. in open excavations, on gravity sewer, it's not standard to the industry. everybody in the sewer biz has bins full of pvc fittings, i'd have to drive 100 miles to get HDPE fittings.

unless you're running large excavators, 20' lay lengths are a miserable son of a bitch. most 22 ton machines are not comfortable handling/pulling 24' boxes. do you fuse the crap in the ditch or up on top and attempt to get it on alignment, on grade, once shoved in the hole?

i can see where it's a great product in pipe bursting jobs...otherwise, looks like an awful lot of extra work to me.

 

[jhark123]

My impression is that, for an equivalent wall thickness, hdpe is more flexible than SDR 35 (I could be wrong). Sewer is laid at a very low slope % and any "dip" caused by a flexible pipe could cause a low spot. That is also why it must be bedded in a substantial amount of pea gravel.

ETA: it also sounds like a lot more work to me.

 

[HUI]

I wouldn't use it for gravity sewer unless I installed with HDD. It works great for force main that is installed by HDD. But anything open cut is SDR 35 or sometimes SDR 26 if your deeper or in close proximity to another water line

 

[JDavis21835]

Dont forget, any fused pipe has lips inside the pipe that have to be machined, or they will catch solids.