Torque Wrench Extension Tools; Torque Multiplication - Daewoo Solar 130LC-V Instructions Manual

TORQUE WRENCH EXTENSION TOOLS

Very large diameter, high grade fasteners (nuts, bolts, cap screws, etc.) require a great deal of turning force
in order to achieve recommended tightening torque values.
Common problems that could occur as a result are:
• Recommended torque exceeds the measuring capacity of the torque wrench.
• Specialized sockets do not fit the adapter on the front end (nose) of the torque wrench.
• Generating adequate force on the back end (handle) of the wrench is difficult or impossible.
• Restricted access or an obstruction may make use of the torque wrench impossible.
• A unique application requires fabrication of an adapter or other special extension.
Most standard torque wrenches can be adapted to suit any one of the proceeding needs or situations, if
the right extension tool is used or fabricated.

TORQUE MULTIPLICATION

A wrenc h e xtension tool c an be u sed t o
increase the tightening force on a high capacity
nut or bolt.
For example, doubling the distance between the
bolt an d t he ba ck (handle) end o f the torque
wrench doubles the tightening force on the bolt.
It also halves the indicated reading on the scale
or dial of the t orque wrenc h. T o accurately
adjust or c onvert i ndicated s cale or di
readings, use the following formula:
I = A x T / A + B where:
I = Indicated force shown on t he torque wrench
scale or dial.
T = Tightening force applied to the nut or bolt (actual Torque).
A = Length of the torque wrench (between the center of the nut or bolt and the center of the handle).
B = Length of the extension.
As an e xample, if a 12" extension is added to a 12" torque wren ch, and t he indicated torque on the dial
reads "150 ft lb," the real force applied to the bolt is 300 ft lb:
The formula assumes that there is no added deflection or "give" in the joint between the
NOTE:
extension and torque wrench. Readings may also be inaccurate:
• If the extension itself absorbs some of the tightening force and starts to bend or bow out.
• If an extension has to be fabricated that is not perfectly straight (for example, an extension made
to go around an obstruction, to allow access to a difficult to tighten fastener), the materials and
methods used must be solid enough to transmit full tightening torque.
Standard Torques
al
A x T 12 x 300
I = =
A + B 12 + 12
Figure 1
3600
= = 150
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S0309000
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