2. mINeRal INSUlaTeD Type THeRmOCOUpleS
Our standard diameters for our MI-cable (mineral insulated thermocouple cable)
Diameter
Type T/C
Sheath Material
0.15
0.25
0.5
1.0
1.5
1/16
3.0
1/8
3/16
6.0
1/4
5/16
1/2
mm
mm
mm
mm
mm
inch
mm
inch
inch
mm
inch
inch
inch
K
K
K,N,J and T
K,N,J and T
K,N,J and T
K,N,J and T
K,N,J,R,S and T
K,N,J,R,S and T
K,N,J,R,S and T
K,N,J,R,S and T
K,N,J,R,S,and T
K,N and J
K
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 316
Inconel 600 or SS 446
13
One of the many advantages of a mineral insulated cable is
the protection offered to the thermocouple wires, afforded by
the metal sheath. For long service life, only contamination free
sheathing of known chemical and physical compositions is used.
The table above lists the most common constructions. Other
diameters and sheath materials are available upon request.
For example: type N thermocouples are available with several
sheath materials of Nicrobel and/or Pyrosil; for the platinum
rhodium thermocouples, which can be higher in temperature,
we recommend to use this in a construction with beads (fg. 1).
For the optimal use of type R, S and B thermocouples we use a
nominal wire size of 0.5 mm as standard. The insulation mate-
rial for this type of thermocouple will be aluminium oxide 99.7%
purity.
Beaded element ceramic insulator with one bead
Beaded element ceramic insulators with several beads
THERMOCOUPLES IN MINERAL INS. CONSTRUCTION