What is the typical design shape of a bourdon tube used in pressure gauges?

The typical design shape of a bourdon tube used in pressure gauges is indeed the C-shape. This design allows for maximum sensitivity and stability when measuring pressure. The main function of the bourdon tube is to convert pressure into mechanical motion.

In its C-shaped configuration, the tube can flex and straighten in response to changes in pressure, which is translated into a rotational movement. This movement is then used to drive the needle on the gauge, providing a visual indication of pressure levels. The C-shape design enables the tube to have a relatively compact size while still maintaining the necessary surface area to respond accurately to the pressures being measured.

Other shapes, such as S-shape or U-shape, do not provide the same level of effectiveness in pressure measurement as the C-shape, as they may not optimize the mechanical action needed for accurate readings or could introduce complications in installation and calibration. Rectangular shapes are also impractical for this application due to their structural limitations, making the C-shape the most widely used design for bourdon tubes in pressure gauges.