Torque values

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tlhunt
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Torque values

Post by tlhunt »

Greetings,
I am putting the wings on a 47 C-140 and wanted to see what torque values are being used for the wing and strut attach points. As you know, the typical reference is the standard torque chart in the 100 Series Maintenance Manual, which specifies a wide torque value range for dash 8 bolts in shear applications. My question is what values are typically being used? 75% of the range? Top of the range? Allowable minimum value? Any insight would be gratefully received and appreciated.

TH
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6643
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Re: Torque values

Post by 6643 »

Look at AC43.13-1B Table 7-1. For bolts with cotter pins, start at the low end and tighten until the holes line up.

The AC is available on line from the FAA.
tlhunt
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Re: Torque values

Post by tlhunt »

Thank you for your kind reply.
I am familiar with the fig. in AC 43.13 that you refer to, and it does specify a torque value range for each bolt size that is quite broad. I was just wondering what actual torque values others were using for wing and strut attachment…?

Thank you again.

TH
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Re: Torque values

Post by 6643 »

For fasteners with cotter pins, I start at the low end, then set the wrench for the high end and turn it until the holes line up or the wrench clicks, which ever comes first. If the holes don't line up, try another nut or a thinner or thicker washer. If there's nothing to line up I set the wrench for the middle of the range.
tlhunt
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Re: Torque values

Post by tlhunt »

That’s exactly what I was inclined to do. Thank you for your time and information.

-TH
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