Eccentric flaring and inner diameter of flare

[lexmark42]

Hi guys,

using an eccentric flaring tool is obviously the better choice when making a flare. However, I noticed that through the rolling motion the orifice of the flare gets smaller than the original inner diameter of the pipe.

Any opinions on this?

To illustrate I have attached two images comparing 1/4 tubing after deburring and with the eccentrically made flare.

Cheers,
-Dave

6680
6681

[Quality]

Looks like the flare is to large (to much tube above the tube clamp) can you fit a flare nut over the flare ?

[lexmark42]

Sure the flare is a bit generous, but it still fits a 1/4" flare nut properly.
I am more concerned about the size of the orifice, which seems somewhat restricted for eccentrically made flares vs. normal ones.
I don't expect it to affect refrigerant flow largely, but I would appreciate your opinion and experiences on that.

I made another flare with the pipe being aligned just flush to the flaring tool:
6682
The right one is the smaller one, the left one is the same as shown before.

The orifice seems wider, albeit just a tad.

Cheers,
-Dave

[cool runings]

.

Just so I understand you! Are you saying that the internal diamiter of the hole is smaller.

I have noticed that when using the eccentric tool that the block seems to crimp the pipe
and that appears to oval the inside diamiter of the pipe.

One thing I did notice was in the picture of the deburred pipe, I would suggest that the deburr
was to much. In my oppinion you only need to clean the inside, not cut it to such an acute angle.

Try deburring it a bit less and see what happens.

As to the narrowing of the internal diamiter I notice it but never gave it much thought.

All the best

coolrunnings

.

[lexmark42]

Hi,

yes, the internal diameter of the hole gets smaller.
The old-fashioned flaring tool extends the tube, whereas the eccentric flaring tool forms the flare by rolling. So I guess that it rolls material not only towards the perimeter of the flare but also to the inside. Thus the somewhat restricted diameter after flaring.

My main concern about this was whether performance could be affected with such a restricted diameter in the liquid line by reducing the flow capacity.

Now I took some measurements:
Inner diameter of the tube after full deburring (I made a chamfer again for easy measurement): 4.3 mm => Area of tube = 14.5 mm^2
Inner diameter of the flare at narrowest point: 11.34 mm^2

This is only 78% of the original area.
Isn't that quite a reduction, albeit only at the joint!

Just for the fun of it I did another flare, this time with less deburring (no chamfer this time). No big difference.

I also noticed the slight ovalness problem, and you get some marks on the outside of the pipe. I don't think either is a problem as long it is minor.

Cheers,
-David.

6683
6684

[lexmark42]

P.S. Inner diameter of the flare is 3.8 mm, area is 11.34 mm^2