Protective tube for a temperature sensor

Protective tube for a temperature sensor, such as a thermocouple, comprising:

• metal inner tube means having first and second open ends;
• non-metallic, thermally conductive plug means having an inner bore portion for receiving the temperature sensor;
• joining means for joining said thermally conductive plug means to said first open end of said inner tube means so as to close said open end;
• refractory ceramic fiber means surrounding at least a portion of an outer surface of said inner tube means, and disposed adjacent a portion of an outer surface of said thermally conductive plug means, at least a portion of said thermally conductive plug means remaining exposed for contacting a material having a temperature to be measured;
• and
• bonding means for bonding said refractory ceramic fiber means to said outer surface of said inner tube means and said outer surface of said thermally conductive plug means.

A protective tube for a temperature sensor, such as a thermocouple assembly, comprising:

• metal inner tube means having first and second generally elongate portions and having first and second open ends, said first portion of said tube means having a substantially constant outer diameter;
• non-metallic, thermally conductive plug means for attachment to the first end of said inner tube means, at least a portion of said thermally conductive plug means having an outer diameter substantially equal to said outer diameter of said inner tube means;
• and
• refractory ceramic fiber tube means having an inner diameter substantially equal to, or slightly larger than, the outer diameter of said inner tube means;
• wherein said refractory ceramic fiber tube means is disposed over said first portion of said inner tube means and said portion of said thermally conductive plug means having an outer diameter substantially equal to said outer diameter of said inner tube means.

A protective tube for a temperature sensor, such as a thermocouple assembly, comprising:

• metal inner tube means having first and second generally elongate portions and having first and second open ends, said first portion of said tube means having a substantially constant outer diameter;
• non-metallic, thermally conductive plug means for attachment to the first end of said inner tube means, said thermally conductive plug means having an inner bore portion for receiving the temperature sensor, and at least a portion of said thermally conductive plug means having a substantially constant outer diameter;
• refractory ceramic fiber tube means having an inner diameter substantially equal to the outer diameter of the inner tube means, and having an outer diameter substantially equal to the outer diameter of said portion of the thermally conductive plug means;
• means for providing a seal at a joint formed by abutting edges of said refractory ceramic fiber tube means and said constant diameter portion of said thermally conductive plug means;
• and
• means for attaching the thermally conductive plug means to the first open end of the inner tube means so as to close said open end of said tube means;
• wherein said refractory ceramic fiber tube means is disposed over said first portion of said inner tube means and is disposed adjacent to said constant diameter portion of said thermally conductive plug means.

A protective tube for a temperature sensor, comprising:

• a metal inner tube having first and second open ends;
• a refractory ceramic fiber outer tube surrounding at least a portion of said metal inner tube;
• a non-metallic, thermally conductive plug having a blind bore for receiving the temperature sensor;
• and
• means for joining the non-metallic plug to the metal inner tube so as to align the blind bore of the plug with the first open end of the metal tube to close said end, and so as to create an interface between the thermally conductive plug and the refractory ceramic fiber tube;
• wherein said first end of the inner metal tube is surrounded by the non-metallic plug, the refractory ceramic fiber outer tube, and means for sealing said interface, and wherein at least a portion of the plug is exposed for contacting a material having a temperature to be measured.