Alundum® and Magnorite® Crushable Insulators

Crushable Insulators

Crushable insulators are available in Alundum® 99.8% fused Al2O3 and Magnorite® 99.5% fused MgO grades.

Insulators are ‘threaded’ on thermocouple conductor wires and inserted inside a seamless metal tubing. The entire assembly is then swaged or drawn down to desired dimensions.

During swaging the insulators crush readily into a powder, compacted around the thermocouple wires, providing electrical insulation resistance.

Outer diameters between 0.5 mm and 12.7 mm are available, with hole diameters in the range of 0.18 mm to 1.75 mm.

The number of holes in an insulator can range from 1 to 6.

Insulator lengths are available in 25.4 mm increments up to 101.6 mm maximum.

Benefits
  • High electrical insulation
  • High thermal conductivity
Application
Material Properties

ALUNDUM® (fused Al2O3) Crushable Insulators AN 900 

  Typical Minimum or Maximum
Al2O3 99.85% 99.65% Min
Fe2O3 0.06% 0.10% Max
SIO2 0.02% 0.08% Max
CaO 0.02% 0.08% Max
MgO 0.02% 0.08% Max
ZrO2 0.0001% 0.08% Max
Na2O 0.02% 0.06% Max
C 0.004 - 0.01% 0.01% Max
S 0.03% 0.005% Max
Cd None Detected 0.001% Max
B None Detected 0.001% Max

* Technical data, right of modification reserved.

 

MAGNORITE® (fused MgO) Crushable Insulators MN 399A

  Typical Minimum or Maximum
MgO 99.48% 99.40% Max
SiO2 0.10% 0.13% Max
Al2O3 0.08% 0.15% Max
CaO 0.24% 0.035% Max
Fe2O3 0.10% 0.015% Max
C 0.01% 0.02% Max
S 0.001% 0.0025% Max
Cd 0.001% 0.005% Max
B None Detected 0.001% Max

* Technical data, right of modification reserved. 

Size

 STANDARD MANUFACTURING CAPABILITIES & TOLERANCES

* Technical data, right of modification reserved

From To Tolerance (mm)
0.5mm 1.4mm

+ 0.050mm

- 0.025mm

1.4mm 2.3mm 3 0.050mm
2.3mm 3.2mm

+ 0.080mm

- 0.050mm

3.2mm 6.3mm 3 0.080mm
6.3mm 9.5mm 3 0.100mm
9.5mm 12.7mm

3 0.0150mm

0.18mm 0.41mm

+ 0.050mm

- 0.025mm

0.43mm 1.73mm

3 0.050mm

1.75mm 7.24mm 3 0.080mm

 

Documents

Data Sheets (TDS)
Specialty Ceramics Thermocouple Insulators - Datasheet

Saint Gobain Specialty Ceramics' products allow customers to solve tough problems in thermal and chemical processing, industrial metrology, temperature

PDF | 600.79 KB
Specialty-Ceramics-Thermocouple-Insulators-Product-Information-web-202972