Thermocouple Insulators

And Insulation

General Information -

Richards ceramic insulators are made from the highest quality raw materials. They are carefully blended for superior mechanical strength and resistance to thermal shock. Our insulators also have excellent insulating properties at high temperatures.  Strict attention to hole size, wall thickness, and other details result in minimum breakage during installation.  Our oval insulator design allows two thermocouples in a single protection tube. Round insulators are also available for dual and single elements.


Beaded or fish spine insulators allow the thermocouple to flex or bend at angles. Short insulators are also available with single, dual or four bores. They are come in 1/2", 1", and 3" lengths.

Junction cups are placed in the bottom of metal protection tubes. This will keep the thermocouple junction from contacting the tube. Furthermore un-grounded thermocouple junctions will always have a junction cup.

The part numbers describe the dimensions of the insulator. See example below.

Example: The part number 823-O signifies an 8 gauge insulator, two holes, three inches long, oval in shape.

Insulation Configurations

Fishspine Ceramic Beads, Braided Glass Insulation, and Junction Cups.

p79 Insulators 20190614
p80 Insulators Pub 20180425-2
p 081 Insulators Full Length 20190520
Thermocouple Insulators


  • Small diameters from .062" to .075"
  • Large variety of sizes in stock
  • Oval or round configurations
  • Fishspine beads for 24-8 gauge wires
  • Available in Alumina, Cordierite, Mullite, and Steatite
  • Available in single, double and four bore sizes
  • Custom cut to length sizes
  • Small or large quantities
  • Glass Insulation
  • Glass Braided Tubing
  • Colored Glass Insulation (Red, Yellow, and White)
  • Thermocouple Junction Cups