Load Pins for Sheave Applications

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Load Pins for sheave applications are designed for measuring line tension. Sheaves are designed with either a variable or constant wrap angle. For the variable wrap angle case, two strain gage bridges are installed perpendicularly (Px and Py). For the constant wrap angle case, one strain gage bridge is installed along the primary (sensing) axis of force (P).

Variable Wrap Angle

For a sheave with a variable wrap angle, the line enters and exits the sheave at 1 fixed angle point and 1 variable angle point.

During installation, ensure that the fixed angle point is oriented along either the X or Y axis. This is referred to as the “Level Line”, which is required for proper operation. If needed, ensure that Px and Py are crosstalk corrected prior to line tension and angle calculations using the Strainsert Crosstalk Correction Data report provided with the job and either the Crosstalk Correction User’s Guide or the Crosstalk Correction Quick Reference, provided separately.

Constant Wrap Angle

For a sheave with constant wrap angle, the line enters and exits the sheave at 2 fixed angle points.

To allow for proper orientation, ensure that the clevis pin and keeper flat are aligned with the axis of maximum sensitivity, which is at the center point of the wrap angle (θ).