What are those ridges inside copper fittings?

[Rocknroj]

so i picked up some copper tee's for my project at and noticed concentric ridges inside the tee where it branches. I looked at several and they are all the same...anyone else notice this? i believe they are nibco brand.. picked up at lowes... what about turbulence? unfortunately i had no old fittings laying around for comparison..

we make a big deal about deburring the pipes to avoid turbulence and then there are these ridges in the fittings.... was going to install to run an icemaker supply... now i think i may be causing more harm than good..


A while back i noticed on some cheap-0 home depot elbows, the curved section inside the fittings were far from smooth.... some old ones that i had in my box were smooth inside... at the time i assumed it was some cost cutting in the manufacturing process.. don't really know why but decided to no longer shop at the home cheapo for copper any more..

 

[Fitter30]

I've have seen this before. Tees are made in a press that they drop a cut length of tubing and with air pressure blow a stub of pipe that forms the tee then machines the three ends and expands the ends . Thats why outside of the fitting is so nice and when the stub is formed ridges are made by the stretching of the metal. Fitting today are made with thinner material than ones that were made 50 years ago and since im not plumbing a space ship im not going to worry about losing any sleep over turbulence caused by ridges.

 

[Sponsor]

 

[Plumber69]

Im pretty sure deburring a line to a ice maker won't matter.

 

[Jadnashua]

I think that you'll find it is a stop to prevent you from inserting the pipe too far.

 

[Bannerman]

I think that you'll find it is a stop to prevent you from inserting the pipe too far.

Correct! Those stop ridges are typically less than the thickness of the pipe wall being inserted into the fitting. As each pipe will be usually touching each stop ridge, the stop ridge will not result in flow turbulance. This is unlike burrs on cut pipes which will be located directly within the flow path.

 

[Sylvan]

Picture a repair coupling ( slip) and a regular coupling with a stop

 

[Jadnashua]

Especially on a T fitting, pushing the pipe in too far could close off the line on the opposite path.

One potential gotcha on a repair coupling is that by its nature, there cannot be a stop or it wouldn't slide. You do need to try to get it centered on the two ends though, so it is useful to mark the tubing so you know you've moved it back properly.