Barometer-Aneroid

Aneroid barometers are instruments for measuring pressure that determine atmospheric pressure by the elastic deformation of the sensing element and transmit readings through a mechanical transmission to an indicating device. Aneroid barometers are used only in normal atmosphere to a depth of 2.5 km.

If it is necessary to make measurements in the depths of the seas, oceans, and even in the air at high altitudes, then serious problems arise that are associated with a large pressure drop and a decrease in temperature. If in such cases aneroid barometers are used, then problems with readings will arise, since a decrease in the elasticity of the aneroid will lead to a weakening of the tension of the spring 8, and this in turn will make it impossible to work by the force of atmospheric pressure. In addition, the anerroid barometer is not suitable for measuring the vertical pressure drop when the rubber column of mercury shrinks due to a change in density under the influence of external atmospheric forces. To eliminate this problem, barometer rods are used, covering the body of mercury from all sides. This measure increases the accuracy of measurements, but contributes to the loss of tightness of the pressure housing and deterioration of the accuracy of height measurements.