Tubular element instrumented with temperature sensors, in particular for measuring overtemperatures in the tubes of thermoelectric power plant superheaters

• US 4,671,675 A
• Filed: 06/02/1986
• Issued: 06/09/1987
• Est. Priority Date: 07/07/1983
• Status: Expired due to Term

• Current Assignee: CISE Centro Informazioni Studi Esperienze SPA
• Original Assignee: CISE Centro Informazioni Studi Esperienze SPA
• Inventors: Arisi, Sergio, Parmeggiani, Aldo
• Primary Examiner(s): Shoap, Allan N.
• Assistant Examiner(s): Will, Thomas B.
• Application Number:
  US06/871,132
• Time in Patent Office: 372 Days
• Field of Search: 374/29, 374/136, 374/147, 374/148, 374/135, 374/208, 374/210, 374/4, 374/110, 136/230, 136/232, 136/233, 165/11.1, 138/DIG. 5, 340/584, 340/596, 340/605, 236/78 B, 236/DIG. 6, 236/DIG. 12
• US Class Current: 374/147
• CPC Class Codes: G01K 1/143 for measuring surface temperatures

Abstract

This invention relates to a tubular element provided with a temperature sensor, in particular for measuring overtemperatures in the tube bundle of superheaters in thermoelectric power plant steam generators, comprising a pair of concentric tubes forcibly locked one into the other by a mechanical plastic deformation process, at least one of the two tubes comprising in the mutually contacting surfaces a series of longitudinal grooves into which temperature sensors are inserted.

Claims

1. A fluid flow conduit comprising an inner metal tube having a bore defining a fluid flow passage, an outer metal tube concentric with the inner tube, the tubes being locked together by mechanical deformation process such that the outer surface of the inner tube is in tight thermal contact with the inner surface of the outer tube along the length of the tubes, at least one of said surfaces having at least one longitudinal groove therein forming with the other of said surfaces a circumferentially closed longitudinal passage into which an elongated temperature sensor has been inserted in a longitudinal direction for measuring the temperature of the conduit.

2. A fluid flow conduit as in claim 1 wherein the tubes are locked together as a result of a drawing process.

3. A fluid flow conduit as in claim 1 wherein the wall of the outer tube has a generally transverse passage therethrough connecting with said longitudinal passage for introducing the elongated temperature sensor into said longitudinal passage.

4. A heat exchanger conduit comprising:

an inner metal tube having a bore defining a fluid passage, an outer metal tube concentric with the inner tube, said tubes being forcibly locked into engagement with each other by a mechanical plastic deformation of the tubes so that the outer surface of the inner tube is in tight thermal contact with the inner surface of the outer tube along the length of the tube, at least one of said surfaces having at least one longitudinal groove therein forming with the other of said surfaces a longitudinal circumferentially closed passage for longitudinally receiving an elongated temperature sensor.

5. A fluid flow conduit as in claim 4 wherein a series of longitudinal welds are provided by an electron beam through the thickness of said concentric tubes in order to improve thermal contact between said tubes.

6. A heat exchanger conduit as in claim 4 wherein near one end of said conduit the wall of the outer tube has a generally transverse passage therethrough connecting with said longitudinal passage for introducing the elongated temperature sensor into said longitudinal passage.

7. In a heat exchanger having an enclosure:

a plurality heat exchange conduits extending through the enclosure with a portion of the heat exchange conduits being positioned externally of the enclosure, at least one of the heat exchange conduits comprising inner and outer heat-conducting tubes coaxially arranged and joined together along their lengths by a deformation process thereby forming a thermal contact area between the outer surface of the inner tube and the inner surface of the outer tube and extending the length of the tubes, at least one of said surfaces having at least one longitudinal groove along the contact area forming with the other of said surfaces a longitudinal circumferentially closed passage for longitudinally receiving a temperature sensor, and the wall of the outer tube, at a location outside the enclosure, having a generally transverse passage therethrough connecting with said longitudinal passage.