Pressure gauges dial sizes & how to select

Pressure gauges and their operating environments

• There are many variations in dial, all tailored to best suit the application and environment in which it is designed to operate.
• The mechanics of an analogue dial is typical throughout, regardless of size or application, and utilises a gear and shaft assembly that fundamentally forces a pointer around a dial when pressure inside the bourdon tube increases.
• Sizes typically range from 1 ½” (40mm) to 16” (400mm)and the size is generally determined by the requirements of individual applications.
• Most common across the industrial HVAC, Process, Oil& gas and Marine markets to which Brannan supply,range from 1 ½” (40mm) to 6” (150mm).

When selecting a suitable dial for a given application there are three main areas of consideration. These are:

Readability

The readability of the gauge simply refers to how well you can see and read the gauge from the location in which an engineer is working. It is a simple requirement that when selecting a pressure gauge, it is readable by the engineer from the area in which they will be working.

Accuracy

The accuracy of a pressure gauge can also be dependent on the size of the dial face, and the more accurate gauges typically dictate a larger dial. This is because accuracy for a mechanical pressure gauge is defined as a percentage of the full-scale range. Having a larger dial allows for the display of smaller, but readable, pressure increments and therefore more accurate display.

Space

The final consideration when selecting dial size is the space in which the dial will be mounted. If you are not able to mount a larger dial into a certain area because of insufficient access or space limitations, then a smaller dial must be considered.It is important to understand that pressure gauges must not be selected on dial size alone,and there are several different criteria that also needs considered before selecting the correct pressure gauge for the intended application.

For more information on any on any of our gauges, please contact sales@brannan.co.uk