Hello All,
I'm installing fuselage fuel lines and looking for some clarity on torque values for the fittings. Specifically I'm looking for torque values for both the AN924-6D jam nut on the AN833-6D 90-degree elbow and the AN818-6D B-nut on the 3/8" flared tubing.
In the Standard Aircraft Handbook, p.203, Table 7-19, it specifies for aluminum alloy tubing, bolt fitting or nut a torque of 75-125 in/lbs for any -6 size hardware. This torque value would seem to apply to ALL aluminum -6D sized hardware
However, in AC43.13, Ch 9 Hydraulic Systems, Table 9-2 it specifically mentions AN818 nuts. It specifies for aluminum alloy tubing a torque of 110-130 in/lbs for a -6D nut. The lower range is significantly higher then the 75-125 in/lbs value in the Standard Aircraft Handbook.
Can anyone shed some light on the correct values for each type of -6D nut? And given the wide torque range each reference gives what initial torque value should I go for on each nut? Lower range? Middle?
Thanks for your time and advice.
Cheers,
Scott
I'm installing fuselage fuel lines and looking for some clarity on torque values for the fittings. Specifically I'm looking for torque values for both the AN924-6D jam nut on the AN833-6D 90-degree elbow and the AN818-6D B-nut on the 3/8" flared tubing.
In the Standard Aircraft Handbook, p.203, Table 7-19, it specifies for aluminum alloy tubing, bolt fitting or nut a torque of 75-125 in/lbs for any -6 size hardware. This torque value would seem to apply to ALL aluminum -6D sized hardware
However, in AC43.13, Ch 9 Hydraulic Systems, Table 9-2 it specifically mentions AN818 nuts. It specifies for aluminum alloy tubing a torque of 110-130 in/lbs for a -6D nut. The lower range is significantly higher then the 75-125 in/lbs value in the Standard Aircraft Handbook.
Can anyone shed some light on the correct values for each type of -6D nut? And given the wide torque range each reference gives what initial torque value should I go for on each nut? Lower range? Middle?
Thanks for your time and advice.
Cheers,
Scott