metric capillary tube

Hello, anybody
May be my question is stupid but yet I want ask it.

There are standard capillary tube I.D. in inches.
And what about standard capillary tube I.D. in millimeters?

I am ordering capillary tube to my supplier 0.054" I.D.
My supplier sent me capillary tube 1.37 mm I.D.
When I am trying check I.D. that capillary tube by pin (Capillary tube gauge № A10971 J/B Industries, AURORA ILLINOIS, USA 60507), pin can't enter in the capillary tube:(

What's reason?:confused:
a) bad pin
b) wrong capillary tube
c) my inefficient hands:D

Thanks for any advice

Could be 'c' but also was the end of the captube burred at all?

Hi Tralex:)

0.040 Thou is near enough 1mm, or at least thatsthe guide I use.

Kind Regards. Andy:)

Thank you Andy and Brian_UK.
The end of the captube was clean and not oval.
Now I knew there are captubes with same outer diameter and different inner diameter. How I can check inner diameter without pin?
Does anybody know some link on the European norm or ASHRAE document ?

Thanks

Hi Tralex:)
to be honest I have never felt the need to measure a capillary ID. They come in a roll, with the ID tagged on it:D
File a pin down until it fits the ID (widest part of the pin) and stick it in a micrometer to fine the diameter of the pin.

Kind Regards. Andy:)

Hi Andy :)
It's good idea. I'll do it.
Thank you very much.:)