Can anyone help me with the AN-xxx numbering system commonly used in fitting systems (as fuel lines, A/C-lines, a.s.o.) from e.g. Aeroquip, B.G. or K.B.?

What will the number after "AN" say?

How can I figure out, which line will need which fitting;
or (the other way round) : a given fitting will need which size of line.


For sure: in the states everyone knows about the correct line for a given fitting.
But over here in germany we use the mm-system in declaring sizes of lines a.s.o.


(Hopefully this question is not putting shame on me...)

Thanks in advance
Zausel

The number after the AN is both the Outer Diameter (OD) & the Inner Diameter (ID) of the hose or fitting. A AN-6 hose would take AN-6 fittings and so forth. Here is a chart from Russell that might help. Since you're in Germany you'll probably have to convert the inches to mm. Russell chart (http://www.russellperformance.com/tech_center/manualrussell_specification.htm)

Both Russell and other manufactures have preset types and sizes of hose for most applications. AN-3 for brakes, AN-6 for fuel etc. Just need to watch out that you use the correct hose for the correct application and the correct fittings for the hose. You can get a regular AN-3 hose for water etc. but for brakes they make a special hose to handle the pressure that brakes need and special fittings for that hose. And a AN-6 hose for fuel that will not be broken down by gas. But again just watch what the manufacturer has already done for you and you will see that they have hose specifically (most of the time) for what you are doing.

Hope this helps.

AN-6 refers to 3/8" hose, the AN number is equal to 1/16" diameter, thus AN-12 would be 12/16" or 3/4". My brother works around aircraft and I have the braid on everything except the radiator hoses.