SILVER AUTOMATION INSTRUMENTS LTD.

BIMETAL THERMOMETERS Product Selection Considerations

When selecting a bimetal thermometer, consideration must be given to the following factors: 

Warning

Selection of the appropriate instrument is the sole responsibility of the user. Improper application or installation may cause product failure, resulting in personal injury or property damage.


Construction

Bimetal Thermometers are furnished with a welded, all-stainless steel stem assembly to ensure reliability. On ranges up to 150°c, the sensing helix is silicone-dampened to ensure smooth operation, accurate readings and excellent readability.


Measuring Range

The measuring range should be selected so that the system temperature falls at approximately the mid-point of the scale. Care should be exercised to ensure that the instrument is not exposed to temperatures greater than the high end of the measuring range.


Process Fluid

The composition of the process fluid should be considered to ensure that it is compatible with the wetted parts of the thermometer and/or thermowell. All thermometers specified for use with corrosive or caustic fluids, or those contained under pressure, should be installed in a thermowell of the appropriate material to protect the stem of the instrument.


Ambient Conditions

The ambient temperature should be considered so that the materials of construction are suited to the application. Bimetal Thermometers are hermetically sealed and are the ideal choice for use in environments where humidity or moisture is of concern.


Installation Requirements

60mm,100mm,150mm dial size Bimetal Thermometers are provided with thread connection for well mounting within a pipeline or tank. The stem should be immersed a minimum of halfway into the pipeline. Flange mounting is also available for air ducts.


Accuracy Requirements

Standard accuracy 1.5, option with 1.0 accuracy


Thermowells

A thermowell of appropriate material compatible with the process fluid should be selected to protect the stem and also allow the thermometer to be removed from the process without shutting down the system. The length should be selected to allow the appropriate immersion into the process fluid. A lagging type thermowell is available to allow for piping insulation.


Liquid Fill

A silicone filled case should be considered on applications where vibration is present. The fill fluid will assist in dampening the internals of the thermometer to improve readability and help prolong the life of the instrument.

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