Protective tube for molten metal immersible thermocouple

• US 5,772,324 A
• Filed: 10/02/1995
• Issued: 06/30/1998
• Est. Priority Date: 10/02/1995
• Status: Expired due to Fees

• Current Assignee: Minco Pipe, Inc.
• Original Assignee: Midwest Instrument Company Incorporated
• Inventors: Falk, Richard A.
• Primary Examiner(s): GUTIERREZ, DIEGO F
• Application Number:
  US08/537,011
• Time in Patent Office: 1,002 Days
• Field of Search: 374/140, 374/179, 136/230, 136/232, 136/233, 136/234
• US Class Current: 374/140
• CPC Class Codes: G01K 1/125 for siderurgical use

Abstract

A protective device for a thermocouple for immersion into a molten metal bath to measure the temperature in the bath includes an elongated exterior protective body, which has an axis and is formed of a refractory composition. An interior reinforcing member is contained within the protective body extending along the axis. The reinforcing member may be in the form of a hollow tubular body which is filled with a refractory cement. A hollow tube is located within the body for protectively housing a thermocouple. A thermocouple for measuring temperatures in a molten metal bath is positioned in the hollow tube.

Claims

1. In combination, a protective device and a thermocouple protected thereby for immersion into a molten metal bath to measure the temperature in said bath comprising:

an elongated exterior protective body, said body having an axis and being formed of a refractory composition,

an interior reinforcing member resistant to bending being contained within said protective body and extending along said axis, said reinforcing member including a bend resistant tube filled with refractory cement, said reinforcing member extending alone a majority of the length of said protective body,

at least one hollow refractory tube positioned within said body for protectively housing said thermocouple, a portion of said tube protruding through a wall of said protective body, said portion being coated with a refractory material,

said thermocouple for measuring temperatures in a molten metal bath being positioned in said hollow tube.

2. A device according to claim 1 wherein said bend resistant tube comprises a hollow steel pipe.

3. A protective device according to claim 1 wherein said hollow refractory tube is formed of quartz.

4. A protective tubular device according to claim 1 wherein said hollow refractory tube has a closed end adapted for immersion into a molten metal bath.

5. A device according to claim 1 comprising at least two of said hollow refractory tubes.

6. A protective tubular device for a thermocouple for immersion into a molten metal bath having a distal end for immersion into said bath and a proximal end adapted to be supported out of said bath, comprising,

an elongated exterior protective body having an axis and being formed of a refractory composition including refractory fibers embedded in a refractory cement or binder,

an interior reinforcing member extending substantially along the length of the central axis of said elongated protective body, said reinforcing member imparting a resistance to bending or bowing of said device when immersed in molten metal, said reinforcing member including a bend resistant tube filled with refractory cement,

at least one hollow refractory tube closed at its distal end and having an open proximal end, said refractory tube being positioned within said exterior protective body parallel and exterior to said reinforcing member, portion of said tube protruding through a wall of said protective body, said protruding portion being coated with a refractory material,

said hollow refractory tube being adapted to receive a thermocouple for measuring temperatures in a molten metal bath.

7. A device according to claim 6 wherein said refractory material comprises a layer or cap comprising graphite.

8. A device according to claim 6 comprising a plurality of refractory tubes.