DOWNHOLE VISUALISATION METHOD

• US 20140340506A1
• Filed: 12/28/2012
• Published: 11/20/2014
• Est. Priority Date: 12/29/2011
• Status: Active Grant

• Current Assignee: Welltec A/S
• Original Assignee: Welltec A/S
• Inventors: Hallundbk, Jrgen, Barfoed, Jens
• Granted Patent: US 10,174,603 B2
• Time in Patent Office: Days
• US Class Current: 348/85
• CPC Class Codes: E21B 47/002 by visual inspection
• CPC Class Codes: E21B 47/12 Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
• CPC Class Codes: E21B 47/26 Storing data down-hole, e.g. in a memory or on a record carrier

Abstract

The present invention relates to a method of visualising a downhole environment using a downhole visualisation system. The downhole visualisation system comprises a downhole tool string comprising one or more sensors, a downhole data processing means for processing the sensor signals to provide sensor data, an uphole data processing means for uphole processing and visualisation, and a data communication link operable to convey the sensor data from the downhole data processing means to the uphole data processing means, the sensors being capable of generating sensor signals indicative of one or more physical parameters in the downhole environment. The downhole visualisation system further comprises a downhole data buffering means capable of receiving the sensor data from the downhole data processing means and temporarily storing the sensor data in the downhole data buffering means.

Claims

1. A method of visualising a downhole environment using a downhole visualisation system comprising a downhole tool string comprising one or more sensors, a downhole data processing means for processing the sensor signals to provide sensor data, an uphole data processing means for uphole processing and visualisation, and a data communication link operable to convey the sensor data from the downhole data processing means to the uphole data processing means, the sensors being capable of generating sensor signals indicative of one or more physical parameters in the downhole environment, the downhole visualisation system further comprising a downhole data buffering means capable of receiving the sensor data from the downhole data processing means and temporarily storing the sensor data in the downhole data buffering means,

said method comprising the steps of:

moving the downhole tool string within a downhole environment,

sensing, during movement, one or more physical parameters using the one or more sensors generating sensor signals indicative of one or more physical parameters in the downhole environment,

processing the sensor signals to provide sensor data,

temporarily storing buffered sensor data in the downhole data buffering means obtained at a pre-set sample rate,

transmitting a first part of the sensor data to the uphole data processing means at a pre-set first transmission rate equal to or lower than the sample rate,

processing the first part of the sensor data using the uphole data processing means and visualising the downhole environment based on the first part of the sensor data,

sending a control signaler from the uphole data processing means to the downhole data processing means based on an event such as a sudden change in one or more of the physical parameters during the visualisation of the downhole environment, thereby changing the transmission rate from the first transmission rate to a second transmission rate,

transmitting at least partially a second part of the sensor data stored in the downhole data buffering means to the uphole data processing means, and

visualising the downhole environment, based on the first part of the sensor data and the second part of the sensor data, chronologically before and after the event without reversing the movement of the downhole tool string.

2. A method of visualising a downhole environment according to claim 1, wherein the second transmission rate is higher than the first transmission rate and lower than the sampling rate.

3. A method of visualising a downhole environment according to claim 1, further comprising a step of deleting the part of the buffered sensor data in the downhole data buffering means which has been transmitted to the uphole data processing means.

4. A method of visualising a downhole environment according to claim 1, further comprising a step of sending an additional control signal to change the speed of the downhole tool string from a first to a second speed.

5. A method of visualising a downhole environment according to claim 1, further comprising a step of changing the sampling rate from a first to a second sampling rate.

6. A method of visualising a downhole environment according to claim 1, further comprising a step of transmitting a second part of sensor data at a second transmission rate and transmitting a third part of sensor data at a third transmission rate.

7. A method of visualising a downhole environment according to claim 1, further comprising a step of visualising the downhole environment based on the transmitted first, second and third parts of the sensor data.

8. A method of visualising a downhole environment according to claim 1, wherein the event is a change in a casing structure, a formation structure or properties of fluids being present in the downhole environment.

9. A method of visualising a downhole environment according to claim 1, wherein the transmission rate is higher than the sampling rate when the sensor of the tool string moves past uninteresting parts of the well.