Bimetal Temperature Gauge

A Bimetal Temperature gauge manufacture largely depends on the manufacture of the Bimetal strip present within.

Temperature Gauges Pressure Gauges Thermowells Thermostatic

Diagram of a bimetallic strip showing how the difference in thermal expansion in the two metals leads to a much larger sideways displacement of the strip.

Temperature Gauges Pressure Gauges Thermowells Thermostatic

A bimetallic coil from a thermometer ( temperature gauge) reacts to the heat, by uncoiling and then coiling back up when the heat is removed.

A bimetallic strip is used to convert a temperature change into mechanical displacement. The strip consists of two strips of different metals which expand at different rates as they are heated.

The strips are joined together throughout their length by riveting, brazing or welding. The different expansions force the flat strip to bend one way if heated, and in the opposite direction if cooled below its initial temperature. The metal with the higher coefficient of thermal expansion is on the outer side of the curve when the strip is heated and on the inner side when cooled.

The sideways displacement of the strip is much larger than the small lengthways expansion in either of the two metals. This effect is used in a range of mechanical and electrical devices. In some applications the bimetal strip is used in the flat form. In others, it is wrapped into a coil for compactness. The greater length of the coiled version gives improved sensitivity.

At Goa Thermostatic Instruments we manufacture Bimetal Dial Thermometers (Bimetal Temperature Gauge) with or without Thermowells. These thermowells are manufactured in line with PTC19.3 in different grades of material for various applications like sea water applications, oil and gas applications.

Refer TABLES for ranges available, connection types and the various options available with the supply of Temperature gauges.

  • "All Stainless Steel" fully welded construction.
  • External zero re-set as a standard.
  • Toughened glass standard, shatter proof glass optional.
  • Weather-proof casing to IP:66, IS:13947.
  • Hermetically sealed casing to ASME B40.3 as an option.
  • Designed to assemble with existing thermowells.
Scope of supply : TG 100 Series Bi-metal Temperature gauges with adjustable connector for connection to process.
Model Number (Typ) : TG 100# Series B-D-R-1-4-S4-S6-06-xx-xx-0/100-3N(1/2"NPT)-AM-E=150-Op0
Case : SS304, Weather-proof to IP:67, IS:13947, bayonet bezel.
Dial Size : 100mm (4”), white background with black numerals.
Pointer : Aluminum, black anodized.
Window : Shatter-proof Glass.
Stem : 6 mm dia in SS316.
Range : As shown against tag nos in °C.
Accuracy : ± 1% FSD.
Overrange protection : 130% FSD.
Zero re-set : Provided at the back of case, by screw rotation.
Connection to process : 3N…½”NPT(M), adjustable connector in SS304.
Stem insertion length : Emm as shown below.
Stem total length : E+50mm.


1) For applications in foggy environment, we can offer “Hermetic Sealed” cases.

*Please note the following parameters can be varied by referring to the model decoding sheet:
Model Number, Case material, Dial Size, Mounting, Stem diameter and insertion length, capillary type and length, Range and unit of measurement required, Accuracy required , and the Connection to process.


© 2019 Goa Thermostatic Instruments Pvt. Ltd. All rights reserved | Design by V3iT Consulting, Inc.