Browse Prior Art Database

Hybrid logging with eLine and fiber optic sensor

IP.com Disclosure Number: IPCOM000246035D
Publication Date: 2016-Apr-27
Document File: 4 page(s) / 183K

Publishing Venue

The IP.com Prior Art Database

Abstract

Downhole telemetry system comprises of data transfer from downhole to surface and vice a versa. In a normal operation the downhole tools send data to surface equipment. However it is also possible that the surface equipment sends commands to downhole tools, requesting a particular set of data to analyze. This publication is directed in particular to a system & method for 'hybrid logging telemetry' (rather than hybrid cable telemetry). Proposed arrangement includes a hybrid logging method with a copper cable & partial length optical fiber cable positioned inside coiled tubing in wellbore. Logging cable has copper electric line ("eLine") all the way and partial length optical fibers from downhole end. The fiber optic cable acts as a sensor in the wellbore & it is physically coupled with eLine before deployment. Under the proposed method, an end to end data transfer between downhole device and surface device is only possible over copper eLine, however intermediate data along the wellbore is received by fiber optics sensor and deliberately routed to a downhole device. The downhole device decodes and converts optical data into electrical signal and sends it to a surface device over copper eLine. This alternate arrangement is distinguishable from existing patented and unpatented methods.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Hybrid logging with eLine and fiber optic sensor

Abstract:

Downhole telemetry system comprises of data transfer from downhole to surface and vice a versa.  In a normal operation the downhole tools send data to surface equipment. However it is also possible that the surface equipment sends commands to downhole tools, requesting a particular set of data to analyze.

This publication is directed in particular to a system & method for ‘hybrid logging telemetry’ (rather than hybrid cable telemetry). Proposed arrangement includes a hybrid logging method with a copper cable & partial length optical fiber cable positioned inside coiled tubing in wellbore. Logging cable has copper electric line (“eLine”) all the way and partial length optical fibers from downhole end. The fiber optic cable acts as a sensor in the wellbore & it is physically coupled with eLine before deployment.

Under the proposed method, an end to end data transfer between downhole device and surface device is only possible over copper eLine, however intermediate data along the wellbore is received by fiber optics sensor and deliberately routed to a downhole device. The downhole device decodes and converts optical data into electrical signal and sends it to a surface device over copper eLine.  This alternate arrangement is distinguishable from existing patented and unpatented methods.

Description:

The operation of this proposed method is optionally purely electro-optical. This requires no downhole power storage since downhole device will be powered by eLine from surface. It uses not a “hybrid cable” but existing eLine coupled with a partial length of an FO used as “sensor” like an “antenna”. The “hybrid cable” referred to in existing methods contains eLine and FO all the way from surface to the BHA. Proposed is a cable that contains copper eLine all the way, and FO partial length, from downhole tool to a chosen length of interest, but not all the way to surface.

Fig 1. Shows an existing system/method described in certain patent(s). Fig 2. Shows an embodiment of the proposed new system/method as distinguishable from the existing system/method of Fig. 1. 

The proposed method includes the following unique embodiments:

·        A telemetry system comprising: a regular (copper) wireline telemetry tool system including a downhole tool which contains a regular wireline (WL) logging head;

·        A length of fiber optic (FO), used as a sensor only, deployed with the copper logging cable, with one end of the FO length coupled to the downhole tool, and the other end of the FO length mechanically anchored to the copper cable (i.e. the FO does not communicate to surface)

·        A downhole FO/WL i...