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Document Title
Fundamentals of Stress and Vibration 2. Engineering Mechanics Chapter
[A Practical guide for aspiring Designers / Analysts]

šƒ’Ž‡ ͵ǣ ϐ‹† –Š‡ ’”‡Ž‘ƒ† ˆ‘” ƒ „‘Ž–‡† Œ‘‹–ǡ •Š‘™ ‹ ȏ ‹‰ ʹǤͷ͸Ȑǡ ™‹–Š ͳʹ ‡“—‹•’ƒ ‡† „‘Ž–•
•— Š –Šƒ–ǡ –Š‡ –‘”“—‡ –‘ „‡ –”ƒ•‹––‡† ‹• ͳͲͲ Ǥ Š‡ ϐŽƒ‰‡ ”ƒ†‹—• ‘ˆ –Š‡ Œ‘‹– ‹• ͲǤʹǤ Š‡
ƒ˜ƒ‹Žƒ„Ž‡ ˆ”‹ –‹‘ ‘‡ˆϐ‹ ‹‡– „‡–™‡‡ –Š‡ ϐŽƒ‰‡• ‹• ͲǤ͵Ǥ ••—‡ –Šƒ–ǡ –Š‡ ‘–ƒ – ’”‡••—”‡ „‡–™‡‡
–Š‡ ϐŽƒ‰‡• ‹• ’‡”ˆ‡ –Ž› —‹ˆ‘”Ǥ

[Fig 2.56: typical flange with bolts]

Solution: the maximum torque that the joint could transfer is determined by the friction
coefficient between the flanges and the radius of the flanges.

In order to find the friction torque, let us assume that the contact pressure between the flanges is
uniform and is given by:

force
Contact pressure = , where force = preload ∗ number of bolts
area

Let us now evaluate the friction torque.

QP No. SSC/Q4401, Version 1.0, NSQF Level 7, Compliant with Aero and Auto Industries, P
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Copyright Diary No – 9119/2018-CO/L