Annealing copper pipe/tubing

[jerry well]

Installing a new ventless propane heater in unheated section of my garage. I have 1/2” copper tube and also some 3/8 copper pipe. Of course the hard copper does not flare for gas fittings like soft stuff.
Any issues with flaring the hard 3/8” pipe so it will flare like soft tubing does? I tried one as a test and seemed to flare just fine after a little heat..... the 1/2 “ tubing came in a roll and near impossible to straighten to look like anything.
Any advice greatly appreciated!
Jerry

 

[Jackfre]

I did a lot of pneumatic control tubing work years ago. We used to take a roll of soft copper and clamp one end to a column and the other to a come along and give it a little pull. Straightens right out and handles much better.

 

[LS6 Tommy]

K or L hard tubing is meant to be flared and swaged. There is no need to heat it to flare it.
Roll the coil of soft tubing like a bicycle wheel with the part you're taking off on the floor. it comes out much straighter that way.

Tommy

 

[rlitman]

I haven't seen hard sticks of 3/8 around here in many years, and I've never encountered K hard tubing at all.

Anyway, yes can can flare hard tubing, but it sure is easier after it's been annealed.

 

[LS6 Tommy]

I've never encountered K hard tubing at all.

All HVAC/refrigeration "stick" tubing is K. K & L are both readily available in soft or stick.

Tommy

 

[jerry well]

Ok , thanks guys....yea, after annealing it flares just like soft copper. Otherwise I did have a split in one.

Let me correct myself here..... the coil I have is 1/2” and the stick I have is 1/2” also, not different sizes, just different types. Soft vs hard.

Is both K and L both rigid? What is “M”?
.

 

[rlitman]

...Is both K and L both rigid? What is “M”?
.

K, L, and M refer only to the wall thickness.

 

[Firebrick43]

hard copper needs a rolling flare tool like a ridgid 345(45 degre)/377(37 degree) or an imperial rol-air 400F (37 degree) or 525F (45 degree)

The cheaper style that smashes a cone head on will cause issues especially if the tubing is "cut" with a tubing cutter.

Copper work hardens and a tubing cutter doesnt actually cut, it swages the tubing/pipe aparts. It works better if you cut with a saw of some type and file square/deburr, and then make your flare... or you can anneal

Stainless tubing is an absolute no no to use a tubing cutter if your going to flare and not really recomment to anneal it either.