I’ve cemented ordinary white PVC pipe of smaller sizes for years. Occasionally I’ve gone as big as 3" or, maybe, 4", but for low pressure applications, and that was quite a few years ago. I want to make something with at least 6" for potable water in my home system, which is driven by a pump and should cycle to 45 psi regularly, higher if the pressure switch malfunctions (quite some time ago an adorable little mouse got in there with sunflower seed shells and partly jammed it, and I watched it cycle upward past 140 psi and peg the gage).
It looks like 6" schedule 40 should be fine, maybe even 8", though in 8" I might want to go to schedule 80 – and 8" schedule 80 plumbing gets pricey fast.
In particular I wonder about cementing joints. I’ve seen people make joints in PVC up to around 18", but there’s a crew of guys doing it and they’re using equipment to slide the pipe home quickly. These are situations where you could be making the last joint in a very expensive assembly, and the pieces slide partway together and then freeze up. I think one is supposed to choose the viscosity of the cement appropriately but don’t know how to.
What I’m doing is making a settling chamber for suspended solids. I have a lot of mica or similar grit in my water and it rapidly fills filter housings before the filter even clogs. We are talking particles of up to a couple millimeters, and they settle rapidly. They sink like rocks. Well, actually, they sink AS rocks. You can settle a lot of them out of kitchen sink tapwater just by running it through a drinking glass. My water’s not turbid, it isn’t really a filter I need, and I’ve bought a centrifugal sand trap but it’s so tiny it would fill up too frequently to maintain easily. My idea is basically to make something like a sink drain trap, with a small emptying port in the bottom. I want it to be able to trap a couple liters of grit before it needs to be emptied.
Thanks for any advice!!