Bourdon tube pressure gauges will be the most regularly used mechanical pressure measuring instruments. Guilt-free is frequently referred to as a Bourdon tube: The French engineer Eug�ne Bourdon made use of this functional principle in the middle of the 19th century. It really is predicated on an elastic spring, a c-shaped, bent tube with an oval cross-section.
The result of pressure on a Bourdon tube
Once the internal space of the Bourdon tube is pressurised, the cross-section is thus altered towards a circular shape. The hoop stresses that are created in this process raise the radius of the c-shaped tube. As a result, the end of the tube moves by around several millimetres. This deflection is a measure of the pressure. It really is transferred to a movement, which turns the linear deflection right into a rotary movement and, via a pointer, makes this visible on a scale.
Sizzles
With the c-shaped bent Bourdon tubes, pressures up to 60 bar can be displayed. For higher pressures, helical or spiral-type Bourdon tubes are used. According to the geometry, material and material thickness, pressures around 7,000 bar could be realised. With regards to the requirement, the pressure elements are made from copper alloys, stainless steels or special materials such as Monel.
Note
Further information on Bourdon tube pressure gauges are available on the WIKA website.