Connecting 6" PVC Pipe Joints

I would not assume that solvent cement joints nor ASTM/IPS-sized piping is "better" for potable water mains necessarily in any regard. One reason I say this is I know that the AWWA series of consensus standards for pvc pipes were developed by reported industry notables many years after the original ASTM standards, and the current AWWA pvc pipe standards as far as I know specifically require rubber-gasketed pipe ends (and do not even allow solvent cement pipe end joints?) Additionally, you should be aware that the ASTM pvc piping piping is generally of a some smaller diameter, lesser carrying capacity and greater pumping energy consumption/cost and other effects etc., arguably weaker/less security/weaker design, and also cannot be dependably joined to existing and widespread existing standardized CIOD pipe or mechanical joint items, at least not without special transition materials.

Also, as far as I know no pvc pipes are readily available with at least integrally formed mechanical joint hubs or bells, to which you could directly attach a Megalug MJ retainer gland etc.

You may be able however to purchase a double-gland harnessing type restraining device that works with threaded steel rods, a gland behind a rubber-gasketed push-on bell, and a spigot end gripper not unlike a conventional Megalug gland that might provide some degree of restraint, but I don't know what the long-term effects of such devices on the plastic might be, nor if such devices would effectively protect the from "over-belling" inward (e.g. if someone/thing were to apply a columnar instead of tensile force, like closing a valve etc., on the piping).

Hello Randy Conner:

just to say you gave a real good answer!

babybear

Hello flyinghigh,

firstly, I will admit I do not know about any of the technical and professional groups as mentioned by the first replying poster.

Given the choice, I would always go for an MJ connection. I have dealt with pvc from half an inch /~13mm, up to four inch /~100mm. And the glued joint gives up after about ten to fifteen years. And a lot quicker if the joint is flexed. It was around buildings, waste, and drain pipes mostly. That may not be the application you had in mind. The good thing with MJ connections is they can relatively easily be mended or renewed quickly. There is also a slight movement in MJ connections which, if used on a hand held device, or one hooked onto a stand makes the holding and directing of flow from the pipe easier.

babybear

Ok, you guys have convinced me MJ connections are the way to go in the larger size pipe; but I will say that the reason so many people have a bad opinion of solvent weld joints is that they assemble them the most common way, which is not the strongest, nor most durable. IOW, they do not remove the surface gloss of either the pipe nor the fitting, with 220 grit emory cloth, or wet and dry sandpaper. This may not sound like much, but it greatly increases the grip and holding power of the joint. I would never install piping where I just slapped some solvent on the joints.

Secondly, they do not use the primer, only the solvent. Here again, is a major mistake, if you're looking for strength and longevity. The primer, when applied to the pipe, then the fitting, then the pipe again, greatly affects the chemical softening of the material, allowing the solvent, when applied in the same manner, to be doubly effective.

Thirdly, they do not twist the pipe/fitting 90º during assembly; and fourthly, do not hold the joint together for a full minute.

All these factors add up to a superior assembly of a solvent weld joint.

Babybear, thx for your input. I would not ever use anything thinner than Schedule 40, or C900; which maybe does not mean you would still not experience the result you did over time, however, it might've. Thx again.

Hello flyinghigh:

No problem. Thanks for your note.

babybear