All Genuine Gurley^TM bending resistance/stiffness testers are based on the same physical principle. each instrument consists of a balanced pendulum or pointer which is center-pivoted and can be weighted at three points below its center. The pointer moves freely in both left and right directions on cylindrical jewel bearings which make the mechanism highly sensitive even to light-weighted materials.

There are two versions available

• Flat sheet
• Tubing

A sample of a specific size is attached to a clamp (parallel for flat sheet materials and tubing clamp for catheters, etc.), which in turn is located on one of several positions on a motorized arm which also moves left and right. The bottom 0.25" of the sample overlaps the top of the pointer (a triangular shaped "vane"). During the test the sample is moved against the top edge of the vane, moving the pendulum until the sample bends and releases it.

On manual/motorized models, the technician must observe the test to discern the maximum displacement of the pointer on the scale. The value (for flat sheet materials) reached is then located on a conversion chart to arrive at the appropriate bending resistance/stiffness measurement.

On digital models, the point of release is automatically measured by an optical encoder and displayed on a digital readout. this readout continuously displays readings from tests performed in both the left and right directions. In addition, the on-board microprocessor automatically computes and displays the average of left and right stiffness data after each measurement is performed. For flat sheet materials, the operator can then press a button to automatically convert the point-of-release reading on the display to force (milligrams) which then can be multiplied by a constant for bending moment (gram-centimeters or millinewton-meters). For tubing, we recommend using the scale reading only for samples of similar dimensions and material.

A complete set of accessory weights is included with every instrument as well as a calibration strip. Whether you are testing membranes or tubing, the Gurley Bending Resistance/Stiffness Tester offers you the greatest range of possibilities.