Thermocouples Probe

Without connectors or Heads


Thermocouple Probes have a maximum service temperature of 1300°F(700°C) depending on the type and gauge of the thermocouple wire used in their construction. The elements are made with impregnated fiberglass wire. The 30 gauge 1/16” O.D. probes have a high temperature limit of 400°F (200°C) due to Kapton insulation on the element. A grounded junction is standard to help prevent the element from pulling out of the tube and to provide a rapid temperature response time.


Optional 1/8” NPT stainless steel compression fitting can be attached by adding a “CF to the end of the part number.  An 1/8” NPT fitting is standard on 1/8” and 3/16” O.D. tubes.   A 1/4” NPT compression fitting is standard on all 1/4” O.D. tubes.

Also, available are Bayonet Fitting (BF) constructions as shown below.


Miniature Thermocouple Configurations

Part Numbering System Examples

Floating Junctions (F) are standard. For Grounded junctions (G), Ungrounded (U) or Exposed Junctions (E) add "G" to "U" or "E" in the part number. Dual elements insert "D" after "4" in part number.

Example: 20K4DP9-U-12

To change the standard type K thermocouple calibration. Substitute the K in the part number with the desired Type B, E, J, K, N, R, S, T, or C calibration.

Example: 20K4P9-G-12 = Type K Thermocouple
Example: 20J4P9-G-12 = Type J Thermocouple

Sheath Materials or Alloy Code

To change the standard Inconel 600 sheath alloy (Richards #9 Alloy Code). Substitute the 9 in the part number with the desired sheath alloy. See the table below.

Example: 20K4P9-G-12 = Type K Thermocouple with Inconel 600 Alloy sheath
Example: 20K4P16-G-12 = Type K Thermocouple with 316ss Alloy sheath

Note: Other configurations are also available.

p34 Miniature Pub 20171004-1
p38 Probes Pub 20171007-2
p38 Probes Pub 20171007-3
p40 Probes Pub 20171008-4
p40 Probes Pub 20171008-5
Mgo Insulated Thermocouples


  • Small diameters from .062" to .075"
  • Many high temperature alloys available
  • Flexible and easy to bend by hand down to two times the diameter of the sheath
  • Short and long lengths
  • Installation flexibility
  • Terminated with plugs, jacks, connection heads or bare leads
  • Very fast response times.
  • Uniquely economical construction
  • All calibrations; Type B, E, J, K, N, R, S, T, C, and P
  • Grounded, ungrounded, in addition to exposed junctions