What the heck is a swing joint? A ballroom of hepcats and zoot suiters?
Well for our purposes a swing joint is made of flexible tubing that attaches the sprinkler head to the lateral pipe. It makes moving the head easier and ensuring it’s straight. It also prevents parts from snapping due to foot traffic. The head has more flexibility when getting kicked around or stepped on. When properly installed a head should be enough to grade as not to be tripped on, but not set so low the retractable riser in pulling in dirt to the wiper seal or sucking sand into the nozzle.
A swing joint must include a street ell under the head or it will not bloody likely sit plumb. A street ell is an elbow with male and female threads. Together with the barbed elbow connected to the flex pipe, it allows full pivotable motion- up, down, side to side. Rookies and sprinkler con-men may try to cut corners and skip the street ell. You end up with a crooked head, because the tension of the flex pipe will leverage the head tilted. No matter how straight you think you’ve gotten it, over time and settling, the head will get crooked- and you’ll have uneven watering: dry spots and swampy ones.
Notice in the cheesy clip art illustration above that I pilfered off the web, the tee in the lateral is plumbed sideways. The elbow coming out of it has give up and down, the pressure of the settling earth does not threaten to snap the fitting. This also makes removal, repair, or replacing the head in the future much easier. And we always assume we are going to have to dig up everything we install, because things happen.
The reason you see illustrations at the DIY big box stores of tees plumbed straight up with short nipples connecting sprayheads is because they make tons of money on those cheap products installed in a way guaranteed to get broken.
BOO! You’re fired! Get off my jobsite!
If you have problem heads that are crooked, too low, or too high, carefully dig one up and see just how it’s connected to the lateral. It’s worth the time to get the heads straightened out properly.
Take a look at this swing joint I dug up the other day. The tee is cut in too close to the head location, leaving an unacceptable radius in funny pipe bend. There is no street ell below head-(not clearly visible, sorry). This will lead to crookedness. Also- a cheap Orbit box-store rotor was installed; all signs point to amateurism, ignorance, and shame. If the radius, or bend in the swing joint is too tight you can kink the pipe, cutting off flow to the head. A lot of knuckleheads get in a hurry and don’t care if the head works right after they bury it.
This drawing below is how I would have installed this swing joint.
