How is assembly torque calculated?

How is assembly torque calculated?

The Torque/Tension Equation is a method used to estimate the torque/tension relationship in an assembly. T = (K D P)/12 can be used to developt a torque value that will achieve a certain tension or clamp load.

How much torque does a 1/4 bolt have?

ASTM A449 / SAE Grade 5*

Bolt Size TPI Tightening Torque (ft lbs)
Plain
1⁄4 20 8
5⁄16 18 17
3⁄8 16 31

How do you calculate prevailing torque?

The prevailing torque will vary less than 75% from the value shown from the first to the fifth installation and beyond. 3) Calculated using formula: Nominal diameter x Clamp Load (from note 1) x Friction factor (dimensionless value of 0.20 for dry installation).

How is bolt tightening torque calculated?

Calculate required bolt torque

  1. normal dry: K = 0.2.
  2. nonplated black finish: K = 0.3.
  3. zinc-plated: K = 0.2.
  4. slightly lubricated: K = 0.18.
  5. cadmium-plated: K = 0.16.

What are the torque requirements for bolts?

The required bolt clamping force for a joint is 20000 lbs. The torque required for a 3/4″ dry steel bolt to achieve this tension can be calculated as. T dry = (0.2) (20000 lb) (0.75 in) = 3000 (in lb)

What are the torque specifications for a metric bolt?

Metric Bolt Torque. If the bolt diameter is 5 mm, thread series is Coarse, ISO 898-1 Property Class is 8.8, then. Torque for Ecoguard Bolt is 4.0 Nm, Lubricated is 4.6 Nm and dry is 6.2 Nm.

How do you calculate bolt tension?

Determine the tension force on the bolt. This can also be measured using a force transducer (again, if the value is not already known). Assume the tension force is 3 lbs. Subtract the preload force from the tension force. In our example, the tension force (2 lbs.) subtracted from the preload force (3 lbs.) gives 1 lbs.

What is the torque for bolts?

Different bolt sizes and grades have different torque specifications. For example, 6 mm bolts with a 10.9 grade have a maximum torque value of 10 foot-pounds, while the same-size bolts with a 12.9 grade have a maximum torque value of 12 foot-pounds. Consult your shop manual for the most precise listings.