Kellukemittarit

Kellukemittarit, often translated as "bell gauges" or "bell meters," are a type of measuring instrument. Their defining characteristic is the use of a flexible diaphragm or a bellows system that moves in response to pressure changes. This movement is then mechanically amplified and displayed on a dial, typically with a pointer indicating the measured value.

These instruments are commonly used for measuring low pressures, such as those found in gas lines, ventilation systems, or HVAC applications. They are known for their relative simplicity, robustness, and cost-effectiveness. The "bell" in their name often refers to the shape of the diaphragm housing or the overall appearance of some older designs.

The principle of operation involves the pressure to be measured acting on one side of the diaphragm or bellows, while a reference pressure (often atmospheric) acts on the other. The resulting force causes the diaphragm or bellows to deform. This deformation is transmitted through a lever system to a pointer, which moves across a calibrated scale.

Kellukemittarit can be found in various forms, including pressure gauges, differential pressure gauges, and even some types of flow meters where differential pressure is used to infer flow rate. Their accuracy is generally moderate, making them suitable for applications where precise readings are not critical but a reliable indication of pressure is required. Maintenance is typically straightforward, contributing to their continued use in many industrial and domestic settings.