Filter and method and distributed temperature sensor system

Patent metadata

Field	Value
Publication number	US-9797783-B2
Application number	US-201615159414-A
Country	US
Kind code	B2
Filing date	May 19, 2016
Priority date	Jun 17, 2015
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A distributed temperature sensor (DTS) system includes a light source; a length of fiber filter having been hydrogen darkened prior to assembly of the system; and a DTS fiber. A method for making a filter for a DTS system.

First claim

What is claimed is:

1. A distributed temperature sensor (DTS) system comprising:
a light source;
a length of fiber filter having been hydrogen darkened prior to assembly of the system connected to the light source; and
a DTS fiber connected to the filter.

2. The system as claimed in claim 1 wherein the light source is a laser.

3. The system as claimed in claim 2 wherein the laser generates light in a range of 1500 to 1600 nanometers in wavelength.

4. The system as claimed in claim 1 wherein the length of fiber filter is about 1 m to about 100 m in length.

5. The system as claimed in claim 1 wherein the length of fiber filter is about 1 meter in length.

6. The system as claimed in claim 1 wherein the length of fiber filter is darkened to remove wavelengths in a 10 to 50 nanometer band about a target center wavelength.

7. The system as claimed in claim 6 wherein the target wavelength is 1385 nanometers.

8. The system as claimed in claim 1 wherein the length of fiber filter is darkened to remove wavelengths in a 20 to 40 nanometer band about a target center wavelength.

9. A method for making a DTS system comprising:
securing a length of fiber having two ends;
exposing the length of fiber to a high hydrogen and high temperature environment for a period of time,
connecting one end of the length of fiber to a light source;
connecting an opposite end of the length of fiber to a distributed temperature sensor fiber.

10. The method as claimed in claim 9 wherein the length of fiber is Germania-free.

11. The method as claimed in claim 9 wherein the exposing is to an environment of pure hydrogen.

12. The method as claimed in claim 9 wherein the temperature is about 25 degrees C. to about 250 degrees C.

13. The method as claimed in claim 9 wherein the exposing is for about 1 hour to about 1 week.

Assignees

• Johnston William Albert
• Mitchell Ian
• Baker Hughes Inc

Inventors

• Johnston William Albert
• Mitchell Ian

Classifications

• G01K11/32 Primary

  using changes in transmittance, scattering or luminescence in optical fibres · CPC title

• G02B6/02114

  characterised by enhanced photosensitivity characteristics of the fibre, e.g. hydrogen loading, heat treatment (treatment of glass fibres by ion diffusion, implantation, radiation, C03C25/60, C03C25/62) · CPC title

• G02B6/02052

  comprising optical elements other than gratings, e.g. filters (comprising gratings G02B6/02057) · CPC title