Home Forums Hunting & Shooting Hunter's Campfire irrigation pipe .. need quick tutorial, please

I may have bit off more than I can chew ... need a bit of expert advice. I'm trying to repair / re-install an irrigation system which is primarily 3 inch diameter aluminum pipe with hook and latch couplers. The female end of each section has a ring inside with a rubber gasket. It also has a threaded spot for a vertical riser for a sprinkler. There are some seemingly fixable sections and some only slightly bunged up risers. I'd like to figure out what size tap and die set to get to repair the "joint" where the risers go into the main line. I heard it called one inch but it looks more like 1-3/8" to 1-1/2" outside diameter. It's been so long since I worked on pipe that I can't remember if it is specified by the ID size or the OD size. Any idea what I should order for tap and die sizes? Then, the second part ... the risers seem to have smaller diameter top ends where the sprinklers screw into the top .. would you guess 3/4ths inch?

All of my tools are for automotive stuff ... this shyte is BIG ... bigger than anything I've worked on.

Thanks ...

Tom, those are pipe threads, tapered. I can't tell you the sizes because aluminum isn't my thing, but I would guess 3/4 at the bottom and 1/2" at the sprinkler (top of riser). Go out in the barn or shop and find a pvc fitting or a faucet or anything you can identify, or run to the hardware store and buy a couple three fittings and take them home and test them in your pipe.

Most all are 1" tapered pipe thread. I have 230 ea of 30' aluminum 3" diameter hand line, about 50/50 hook and latch or drop-lock. They work well if you have good gaskets in them, but the various manufacturers used varying gasket designs. If the holes for the riser pipes are bigger than 1" you might need to thread what you have and use a reducer to 1" or bush the 1" riser to the new bigger diameter.

Because my property is irregularly shaped, I don't use the 5" or bigger feeder lines to hook it to the well. I use lengths of 3" lay-flat hose, clamped onto the top end piece and use Ts at each run with 3" PVC valves.

IRRIGATING MY LOWER FIELD WITH HANDLINE:

I still hate handlines.

It sounds like you’ve got 1” NPT saddles.

https://amzn.to/2Gua7s9

Sounds like 1” to me, buy a 3/4 and a 1” nipple at the hardware store. I would bet on the 1”

Thanks!

Pipe goes by the inside diameter

Is it the inside diameter that you specify for the taps and dies, too?

I’m all but certain you need a 1” NPT tap. I put a link above. The nominal dimension for pipe, in this case 1”, refers to the tube ID. This dimension does not directly correspond to the thread size, like it seems to with a bolt. Even in the case of a bolt the diameter dimension would refer to the OD of the bolt shank. Unlike bolts, pipe threads are tapered. If you're not sure what size you have, take Hanco’s advice and buy a couple schedule 40 pipe nipples of known sizes and see what fits.

The cranberry industry doesn’t use alumnium hook and latch irrigation pipe anymore, but 30 years ago it was a mainstay. Everything’s been converted to Drisco and buried. Just a few years ago, I scrapped 17,000 lbs of aluminum irrigation pipe. I’ve still got a few crates of miscellaneous fittings, adapters and do-dads, that I couldn’t bring myself to scrap.

I'm pretty sure it is 1" ID pipe. threading into the main 3 inch line at the joints. The remaining question is the sprinklers ... these "risers" are about 3 feet tall. The top 4 inches necks down to some smaller size, possibly 3/4ths, where the sprinkler heads attach. Wild guess is 3/4ths inch. I'm having a surprising amount of difficulty finding a hardware store with the right tools. Lame. If I don't find anything this afternoon I'm going to gamble and order online w/o actually being able to check first.

Are you looking for bells (reducer couplings)? What size impacts are you using? What size riser (1”MNPTx36”x3/4F)? Are these standard aluminum risers finished with a swedge fit zinc bell for the impact sprinkler or are both ends of the riser threaded 1”MNPT? Can you post some pics. Do you have a local irrigation supply?

Risers
https://www.irrigationsupplyparts.com/product/aluminum-riser-pipe/

Bells
https://www.irrigationsupplyparts.com/product/bell-reducer/

The impacts are brass or bronze. They are either 3/4 or 7/8 inch thread on the bottom. The risers are galvanized steel pipe. I think we have established that they are 1 inch ID. Instead of some sort of fitting to neck down for the impacts, the riser pipes themselves constrict at the top and are threaded to match the impacts.

I went to the irrigation supply that serves the orchards yesterday. They sell pipe but don't sell tools. They sent me to a hardware store which apparently had some of what I wanted but didn't want to sell it to me. (WTF? This valley is WEIRD that way.) I ordered stuff online last night. I'm fairly confident about the 1" NPT tap and die. The 3/4ths for the inside of the risers / outside of the impacts is just a guess.