Example 2: Container weighing

The combined center of gravity S of the suspended container lies below the level of the load cells.

It is mounted on three lugs, has an empty weight (total load) of 1.2 t and a maximum capacity of 1.8 t. The container has a diameter of 1 m (3.3 ft). Weighing of the individual components produces a chemical reaction that raises the temperature of the container with contents from approx. 18 °C to approx. 55 °C (131 °C).

Selection of load cells and mounting components

We recommend using 3 SIWAREX WL280 RN-S SA load cells with a rated load of 2 t (1.97 tn. l.) (for determination of the rated load: please refer to introduction). Due to its low constructional height, the WL280 RN load cell was selected.

Container weighing with SIWAREX WL280 RN-S SA load cells and self-aligning bearing

Self-centering self-aligning bearings are used as mounting components as the container is suspended and cannot lift up from the self-aligning bearing.

The 37 K temperature rise will cause the diameter of the container to increase by 0.4 mm (0.02 inch).

The self-aligning bearing permits a maximum oscillation path of ± 4 mm (0.16 inch) and is therefore able to accommodate the temperature expansion of the container.

An oscillation limitation is not necessary because there is a small gap of b = 3 mm (0.12 inch) between the container and the platform. In this case, the platform acts as an oscillation limitation.

For wider gaps in other applications, either compact installation units have to be used (instead of the self-aligning bearings) or external pendulum limiters must be provided as an alternative.

Configurator for container weighing (basic configuration)