torque table help????

[AirbusPilot]

Hi,

Could you please light me in this question, I have been trying to find torque values for AN fitting and screws (I want to intall my fuel tanks within the correct values) in this two FAA book without any luck

AC 65-9A and AC 43.13 1b

Find the correct values for bolt is eassy also they are in Vans manual but not for AN fitting and Screws.

PLEASE HELPPPPPPPPPPP!!!!!!!!!!!!!!!!!!!

[kentb]

The value were in a chart towards the front of the preview plans binder.
About the 10 page in IIRC.

Kent

[lucaperazzolli]

Hi,

some information for you from Mechanical Toolbox CD (great source !).

Hope this help

-------
There is no standardized method of tightening a tapered pipe fitting. One advantage of tapered pipe fittings is that you can position an elbow at any angle you desire by tighening a little more or a little less. Your best bet is to follow the standards for your industry. What follows is a rather lengthy discussion of problems you might encounter using all of the commonly used methods. This will help keep you out of trouble when your "industry standard method" fails.

LEAKS:
Tapered pipe threads leak because there is a gap between the top of the male thread and the bottom of the female thread. Tightening doesn't remove this gap, so tightening isn't done to stop the fitting from leaking. Proper application of thread sealant prevents the fitting from leaking.

TORQUE:
Torque works fine until you use a fitting that is out of spec and bottoms out in the boss before reaching torque; Or you reach the specified torque and the fitting is pointing in the wrong direction, or the threads are of poor quality or damaged and torque is reached before the fitting is properly engaged. Torque is not always practical with tapered pipe fittings because of the wide differences in friction (material, pipe dope, Teflon tape). Torque will sometimes get you in trouble; understand its weakness and use other quality assurance methods along with torque.

FEEL:
Most screwed pipeing is tightened until it feels "right" and the fitting is pointing in the desired direction. What the experienced mechanic is often "feeling" is how the fitting is getting tight. Screw it into until it starts to seat. Then up the force a little by yanking. If each yank gives less movement, you probably have a sound joint. If the movement stops suddenly, you have probably bottomed out. The experienced plumber knows when to stop before he damages the fitting or boss.
Caution is advised, tapered pipe fittings can crack an aluminum boss if over tightened. This is especially true when using Teflon tape because the low friction of teflon makes it easy to over-tighten.

Number of Rotations:
Included in the standards for NPT and ANPT are engagement length, both straight and wrenched. For example, a 1/4 inch tapered pipe fitting should screw in 4.1 threads until finger tight (handtight engagement), and 3 threads for wrench makeup. One problem is the wide variance in quality of the fittings and threads. Few 1/4 inch fittings screw in 4.1 threads before they reach finger tight. As a general guideline, after hand-tight engagement, tighten 3 full turns for sizes up to 2 inches for NPT fittings.

Cross-treading:
Perhaps the most common fault a beginner makes is cross-threading the fittings and not realizing it. The male thread fitting needs to be aligned with the axis of the tapped hole. Rotation force should gradually increase with tightening.

Comment:
Torque alone is an unsuitable method of specifying how a NPT fitting should be installed. Other conditions, such as type of thread sealant, direction of elbow, number of turns, and recognition and pre-inspection of thread quality also need to be included with any torque value.

-------

[Transporter]

See Table 9-2, page 9-19 in Advisory Circular (AC) 43.13-1B, Change 1 (ISBN 0-89100-306-1).

Although the chapter covers hydraulic systems, the table should provide the information you need.

This table provides torque minimums and maximums for AN-818 tubing nuts as well as tubing bend info.

Another reference is the "Standard Aircraft Handbook" by Larry Reithmaier (ISBN 0-07-134836-0). This book also has a table (page 183) for tubing bends and torques...bends are the same as the above reference but torque values are different; if in doubt, I'd go with the AC.

Regards,
Mike

[Webb]

I don't remember where I found it but I took a Sharpie and wrote the inch pounds right on the front of the case I keep the wrench in.

All listed as inch pounds
AN3 20-25
AN4 50-70
AN5 100-140
AN6 160 - 190
AN7 450 - 500
AN8 480 - 690
AN9 800 - 1000
AN10 1000 - 1500

Beats looking it up. I set it at the low end and click it a second time when tightening.

[AirbusPilot]

Originally Posted by Transporter

See Table 9-2, page 9-19 in Advisory Circular (AC) 43.13-1B, Change 1 (ISBN 0-89100-306-1).

Although the chapter covers hydraulic systems, the table should provide the information you need.

This table provides torque minimums and maximums for AN-818 tubing nuts as well as tubing bend info.

Another reference is the "Standard Aircraft Handbook" by Larry Reithmaier (ISBN 0-07-134836-0). This book also has a table (page 183) for tubing bends and torques...bends are the same as the above reference but torque values are different; if in doubt, I'd go with the AC.

Regards,
Mike

Thanks Mike that is exactly what I was looking for!!!!!!!!!!