L&W Bending Tester is quick and easy to use. A test piece is placed in a clamp. When the operator presses the start button, the clamp closes about one end of the test piece. A support holds the test piece in place before the measurement. This helps the operator and leads to a repeatable measurement process. When measuring, the support is automatically lowered and does not hinder the movement of the test piece. If the auto-touch function is selected, the clamp turns slowly to move the free end of the test piece in contact with the load cell. The test piece is bent to the selected angle. The instrument records the force throughout the measurement process. The clamp then returns to the start position and the test piece is released.

The chosen measurements are automatically shown in the display and printed on the built-in printer.

Measures creaseability too

Creasing is performed when converting board and makes the material easy to fold in the right places. A large number of properties are calculated from the measurement curve’s bending moment relative to the angle (bending moment = force x length of bend), which facilitates the assessment of how the board should be creased when converted. When measuring creaseability, two sample groups are prepared and tested: one group with uncreased test pieces and one group with creased test pieces. The measurements are carried out as normal, but often with a bending angle of 90°.

For good measurements, it is crucial that the test piece is firmly held in place. This is achieved with pneumatic clamps that secure the test pieces with 200 kPa between level, parallel jaws.

Load cell with auto-touch function

Auto-touch means that the test piece is brought into contact with the load cell with a small, predetermined force. From this position the test piece is bent through the predetermined angle. The benefit of the auto-touch function is that no manual intervention is required to place the test piece in contact with the load cell; without this function, it can be difficult and time consuming to ensure that the same force is used each time.

Easy to get started

All configuration and programming is done only once via a computer. Thereafter, the computer is disconnected from the instrument. The instrument is then controlled through pushing one or two buttons on the instrument panel. The most common configurations are pre-set at the factory.

If requested, the instrument can be configured so that the operator is given guidance on the order of measurement within the measurement series. Checks and calibration are easily and rapidly performed, with the aid of the weight platform included (calibration weights are not included).