Bayonet Thermocouple

A Bayonet Thermocouple is a type of thermocouple which uses a Bayonet type mounting for process connection.

It can be said Bayonet mount or a Bayonet Fastener is a fastening mechanism which consists of a cylindrical male side with pins mounted radially, and a female receptor with L-shaped slot(s) which matches the pins and with spring(s) which forces the parts to stick together.

This type of connection is most commonly found in electric bulbs.


  1. Thermocouple Type J, K, or N Standard Limits of Error ± 2.2°C or 0.75% (which ever is greater)
  2. Thermocouple Type T Standard Limits of Error ± 1.0°C or 0.75%; (which ever is greater)
  3. Thermocouple Type E Standard Limits of Error ± 1.7°C or 0.50% (which ever is greater)
  4. Thermocouple Type R or S Standard Limits of Error ± 1.5°C or 0.25% (which ever is greater)
  5. Thermocouple Type B Standard Limits of Error ± 0.50%

The six standard design’s are available to meet the requirements for space conservation while the cap and spring are provided to insure optimum contact with the process. With a pipe clamp adapter, the sensor can also be used to measure pipe wall and bearing temperatures.

These six configuration are divided into two parts:-

Adjustable Immersion

  • Bayonet on Flex Armor
  • Bayonet on Flex Armor with transition
  • Bayonet on Spring

Fixed Immersion

  • Bayonet Straight
  • Bayonet 45° Degree Bend
  • Bayonet 90° Degree Bend
  1. Adjustable immersion Bayonet Cap On Flex Armor.
  2. Adjustable immersion Bayonet Cap On Flex Armor & Transition
  3. Adjustable immersion Bayonet Cap On Spring
  4. Fixed immersion Bayonet Straight
  5. Fixed immersion Bayonet 45° Bend
  6. Fixed immersion Bayonet 90° Bend

Applications :

  1. Used in extruder & Plastic processing industries.
  2. These sensors provide accurate temperature control for the best plasticizing combination of plastic material , mold & design.
  3. Used in die casting industries.
  4. Used in packaging & other industrial sensing application.