Suggest using 'aerospace hydraulic quality' 6061 tubing... not general purpose/older spec... drawn tubing.
The following tube-specs pass rigorous inspection/testing for this very purpose...
6061-T4 HYDRAULIC TUBING MIL-T-7081 or AMS-T-7081 or AMS4081
6061-T6 HYDRAULIC TUBING MIL-T-7081 or AMS-T-7081 or AMS4083
NOTES1.
A. System working pressure, proof-pressure [test] and burst-pressure [ultimate] requirement should be carefully evaluated for intended use... so Diameter-VS-[standardized] wall thickness has to be determined by YOU.
B. WW-T-700/6 and AMS4082 or AMS4080 or any commercial grade [ASTM, etc] drawn tubing... are also acceptable when carefully evaluated/tested... but these are made to older standards which are not optimized for applications where tight/quality-bending, single or double-flaring and swaging are required.
C. DRAWN or extruded/drawn Tubing... ONLY... never simply extruded tubing... should be used in fluid applications. Lotsa reasons.
There are several documents/manuals for aircraft quality tubing-assembly [tube selection, cutting/trimming/bending + flared and/or swaged end-fittings + corrosion protective finishes + inspections and proof-testing + installation + markings]...
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BTW: 'AN-5 fluid fitting(s)' simply don't exist... no earthly idea what You are referring to.
There are however hundreds of different aerospace fluid-fitting types available.
I have a nicely illustrated catalog that is useful for-pick-n-choose... but it's too large a file to be up-loaded, in E-T. Other fluid-component document references are meaningless without access to the other documents it references.
Regards, Wil Taylor
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