Rigsite for LWD. (Lesson 11) презентация

Depth Measurement
All LWD data depend on accurate depth measurements.
Accurate depth monitoring is vital to the success of the LWD job.

Depth Measurement Process
Computer
Depth sensors data are processed and added to the T/D dataset

Types of Failure or Error
Mechanical failure
Software failure
Human Error
Three possible ways to introduce error into the Time/Depth data:

Accurate Depth Monitoring
Vigilance catches depth errors at each connection
Vigilance catches on/off bottom errors before they cause bad data
Maintaining an accurate time/depth dataset requires constant vigilance:
Vigilance produces an accurate time/depth dataset.

Time/Depth Datasets
Entries in the time/depth dataset are tagged with a T/D activity and on/off bottom status.
The time/depth dataset is the depth versus time data for a run.
The accuracy of all reported sensor data depends on an accurate time/depth dataset.

Time/Depth Dataset

Activating the Depth Monitor
If the icon is grayed out, the computer is not configured to monitor depth. Reconfigure to activate it.

Depth Monitor

Depth Configuration

Changing T/D Activity

Changing T/D Activity

Logging Out of the Hole
Set a new T/D activity in the depth monitor
Used until changed by the operator
Any named T/D activity must reflect professional standards
To identify wipe section data, it must be tagged with a unique T/D activity :

Surface Sensors
Accurate calibration and reliable operation of surface sensors are critical to the LWD job.

Depth Calibration
Enter the factors for installed sensors in this dialog box

Depth Calibration

Drawworks Calibration

Drawworks Calibration

Pipe Tally Sheet
Copy the pipe joint lengths from the driller's pipe tally to the LWD pipe tally sheet
Use the tally sheet to keep a master record of hole depth
The Driller’s pipe tally is the final authority on well depth:
An accurate time/depth record is vital to the LWD job.

Using the Pipe Tally Sheet

Depth Control Review
Importance of depth monitoring
T/D dataset
Depth monitor
Depth configuration
Depth calibration
Pipe tally

Sources of Depth Errors
Incorrect entry in tally sheet
Driller used pipe out of order
Not drilling to same spot on kelly
Depth sensor slipping
Depth calibration error
Inaccurate on/off bottom
The most common causes of depth error are:

Incorrect Entry in Tally Sheet
First, check for errors in the tally sheet
Possible sources of error in the tally sheet
Incorrect addition
Transposed numbers
Entries out of order
When there is a difference between the IDMS depth and the tally sheet:

Driller Used Pipe Out of Order
The depth differences will even out after two or three connections
Size of the depth difference depends on difference in length between connections
Get the order used (if known) and make the changes in the tally sheet
When the driller picked up pipe in an order different from the tally book:

Pipe Used Out of Order
Depth drilled = 95.71 ft
Tally length stand 1 = 97.05 ft
Total difference 1.34 ft
Depth drilled = 97.05 ft
Tally length stand 2 = 97.11 ft
Difference 0.06 ft
Difference for 2 stands 1.40 ft
Depth drilled = 97.11 ft
Tally length stand 3 = 95.71 ft
Difference - 1.40 ft
Difference for 3 stands 0.0

Inconsistent Kelly Down
Drilled depth does not equal the length of the stand
IDMS depth does not match the tally book
Depth differences vary from stand to stand
Depth differences even out as drilling continues
If the driller does not drill to the same spot on the kelly each time:

Inconsistent Kelly Down

Depth Calibration Error
Same error showing up on each stand is a calibration error
A small error may require several stands to become apparent
Correction for this error is to recalibrate the sensor
Calibration errors show up as a consistent gain or loss of depth:

Calibration Error
Measurement Error - 0.58 ft
Depth Error = - 0.58 ft
Measurement Error - 0.58 ft Hole Depth Error
(- 0.58 ft + -0.58 ft = - 1.16 ft)
Measurement Error - 0.57 ft
Hole Depth Error
(-1.16 ft + -0.57 ft = - 1.73 ft)

On Bottom Early
Spike in the ROP at beginning of a stand
Positive hole depth error at end of stand
IDMS on bottom before bit is actually on bottom causes:

On Bottom Early
6.11 ft hole depth error

On Bottom Late
Caused by
Less compression on pipe (less WOB)
Error in sensor reading (slipping)
Gap in the data when plotted unless corrected
IDMS depth not on bottom when bit is drilling:

On Bottom Late

Crown Wheel Slipping
Most likely to slip during fast movement of the drillstring
Hot weather can contribute to slipping
Wet conditions can contribute to slipping
Can cause inaccurate INSITE on bottom tracking
Crown wheel slipping causes erratic differences between tally and INSITE bit depth:

Crown Wheel Slipping
Measurement Error - 0.58 ft
Hole Depth Error = - 0.58 ft
Measurement Error 0.79 ft Total Depth Error
(- 0.58 ft + 0.79 ft = 0.21 ft)
Measurement Error 1.13 ft
Total Hole Depth Error
(0.21 ft + 1.13 ft = 1.34 ft)

Time/Depth Editor Functions
Find
Expand and compress
Shift
Insert and append
Delete
Edit single records
Functions of the Time/Depth editor are:

Editing the Time/Depth Dataset
Always back up the Time/Depth dataset before editing.
After editing do a Time/Depth Recorrelation in Processing Monitor to apply changes
Caution
Do not change the Time/Depth dataset until all other possible remedies have been tried.

T/D Editor

T/D Editor Graphic View

T/D Editor Graphic Functions

Time/Depth Review
Sources of depth error
Time/Depth editor layout
Editing functions and when to use them
Graphic display

Real-Time Data Display
Six applications display real-time data
Real-Time Displays
WellView
Session Log
Real-Time Table
DDU
Real-Time Charts

Real-Time Displays
Real-time displays are customized for specific tools or situations:
Built up from elements called controls
Give a familiar form to the data
Display any type of data
Changes display at set limits
Saved as .rtf files in the INSITE/Data/ RTDisplay folder

Real-Time Setup Files
Applications with real-time displays (except DDU and WellView) can save the setup parameters:
Saved in the INSITE/Data /application folder
Opened from System Manager/Displays application set
Default and saved templates for each application can be copied to other computers

DDU Display
The DDU provides the driller with real-time steering information:
Display unit mounted at driller’s station
Displayed on INSITE computer
Has 2 information areas
Directional toolface display
Alphanumeric display

Real-Time Table
Real-time tables are customized for specific tools or situations:
Easier to read actual values than plots
Highlight data outside limits
Display any variable in the datasets
Saved as .rtt files in the INSITE/Data/ RTTable folder
No historical data

Real-Time Table Display

Real-Time Charts
Real-time Charts:
X,Y plot or bar chart of selected data
Used to monitor critical surface parameters such as pit volume
Used more by mud loggers than LWD

Real-Time Chart Example

Session Log
Record of all information received and operations performed by INSITE:
Scrolling sequential record of all input and output from the database
Each entry is time/date indexed
Provides help in troubleshooting
Viewed through System Manager/ Displays/Session Log

Session Log continued
Realtime or historical mode
Can view previous Session Logs
Previous Session Log files are named with time and date of last entry
Session Logs can be backed up during ADI export

Session Log
Sequential Activity in INSITE

WellView
WellView is a graphic presentation of the drilling track:
Provides a visual display of well progress
Memory intensive
Generally not run by LWD engineer
Run on customer workstations

WellView Example

Layout
Layout provides a set up of real-time displays:
Contains templates for different job situations
Templates can be modified for specific job situations
Saves custom layouts
Changes layout when drilling activity changes with sequencer

Layout

Layout

Real-time Display Review
DDU
Tables
Plots
Session log
Layout