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8.0 - Database Tree
The organisation’s database is arranged into a hierarchy known as the database tree.
Figure 84: SQL Database Tree
Currently the operator level is available to be edited from the Web Portal. Other levels must be created in Well Seeker Pro.
Operator level represents a specific oil company or directional company, and where the user sets the rules for anti-collision and daily reporting phases and activities for all fields, facilities, and wells under it. The Operator page allows the user to create, remove and edit the properties of operators in their organisation’s database from within the Web Portal interface.
Figure 85: Operator page functions
The user can add a new operator using the edit menu, which is opened by clicking on the icon in the bottom right of the page and has the following functions:
Add: Adds a new operator to the database.
Refresh: Refreshes the page.
Clicking on an Operator will open the Edit Operator window. Clicking on the icons to the right of each operator will open the Activities, Phases and Warnings windows.
Clicking on the red trash bin icon to the right of each operator will delete it. Note that this will delete all fields, facilities, and wells for this operator in the organisation’s database.
The Edit Operator window is where the user can set the operator’s name and details. It is also where the anti-collision rules for all wells under the operator are set.
Figure 86: Edit Operator window
Operator name: The name of the operator that will be used throughout the Web Portal.
Address: Contact address for the operator. This is for information purposes only.
Contact: Contact name for the operator. This is for information purposes only.
Anti-Collision Scan Method: The anti-collision scan method used for all proximity scans. Three options are available:
- 3D Closest Approach: Finds the closest approach of the offset well in 3D space. To visually represent the scan, imagine an ever-expanding sphere with its origin at the point of interest on the reference well. The point on the offset well which first touches the sphere is the point of closest approach. A 3D scan will always find the point of closest approach regardless of which direction the offset well is coming from.
- Travelling cylinder North / High side: The scan describes a circular plane perpendicular to the wellbore. To visualize, imagine a 2D disc with its origin at the point of interest on the reference well with its axis perpendicular to the well bore. The point at which the offset well intersects the disc is the point of closest approach. Travelling cylinder scans can miss or be very late to detect offset wells which approach near perpendicular to the reference. This scan should be used with caution or when backed up by an accompanying 3D closest approach scan. The difference between the North / High side scans is simply the reference angle used when determining the direction of the offset well. High side references the offset well to the high side of the current well bore, this can lead to confusing outputs as at low inclinations the high side of the wellbore can swing dramatically between survey points. North referenced travelling cylinder scans use North (True or Grid, whichever is selected at Field Level) as the reference where the high side angle is calculated and the current wellbore azimuth is added.
- Horizontal Scan: Finds the point of closest approach of the offset well by scanning horizontally on the reference wells current TVD. This scanning method is rarely used as it can miss potential collisions.
Figure 87: Anti-collision scan methods
Error Surface: The error surface used to calculate centre-to-centre distance, ellipse separation and separation factor. Three methods are available:
- Circular Conic: Uses the ellipse semi major axis as the error radius regardless of which direction the wells are approaching from. This can lead to very pessimistic AC results.
Figure 88: Circular conic error surface
- Pedal Curve: This method describes the errors as an ellipse (elliptical conic); however, it uses the pedal radius in separation factor calculations. This is the radius of the ellipse perpendicular to the line of closest approach.
Figure 89: Elliptical conic error surface
- Combined Covariance: This method uses the same error radius as elliptical conic; however, the total error radius is calculated by root sum squaring (RSS) the two radii. This method should be used only with errors at 2.79 Sigma and above.
Errors Calculated From: Allows the user to define where the EOU calculation starts from. For land wells and jack-ups, “surface” is usually selected. However, for deep water wells, “mudline” is usually selected.
Include Casing: Allows the user to decide if the casing radius is to be considered in the anti-collision calculation.
Casing Method: If Include Casing is turned on, this option defines how the casing radius is used in the separation factor calculation.
- If “Add” is selected, the radius is added to the error radius and survey bias:
- If “Subtract” is selected, the casing radius is subtracted from the centre-to-centre distance. It should be noted for top hole sections where the centre-to-centre distances are small, this option can give a negative centre to centre distance:
Error Output Sigma: This is the number of standard deviations with which the errors are displayed, and the warning levels are calculated, and they represent a level of probability. The below table represents the confidence levels for one, two- and three-dimensional Gaussian distribution with equal standard deviations in all directions.
When using the Pedal Curve method (as is used within Well Seeker), the probability of collision is effectively broken down into a one-dimensional problem, therefore at 1 sigma there is a 68% chance that the well path will reside inside the EOU and this increases to 95% at 2 sigma. This value also determines at what sigma level the error ellipse sizes are displayed on the error ellipse report. The below picture shows a visual representation of the pedal curve around an ellipse of uncertainty.
Figure 90: Pedal curve
Travelling Cylinder Safety Factor: Allows the user to apply a safety factor to the errors which are generated in the travelling cylinder plot. With a value of one entered here (default), the ellipses will generate as per normal. If the user enters a value of, for example 1.2 here, the ellipses displayed on the TC plot will be 20% larger, 1.5 will be 50% larger etc, giving the safety factor required. Note: This value cannot be anything less than 1.
Directional Company: Used to signify if the customer is a directional company instead of operator. This changes the ‘directional company’ field to ‘operator’ in the Update Personnel window in the Daily Reports page.
Locked: This will lock the operator properties window when accessing the operator via Well Seeker, but will not require a password to be unlocked.
Activities are used in the daily activities section of Daily Reporting to categorise drilling activity, which then allows the Web Portal to track drilling data such as drilling and circulating hours. This data can then be used in reports and in KPI tracking.
Figure 91: Activities page
The user can add new activities using the edit menu, which is opened by clicking on the icon in the bottom right of the page and has the following functions:
Add: Adds a new activity to the list.
Refresh: Refreshes the page.
Each activity has an abbreviated code which is used in the daily activities and then a description to help define the activity. Clicking on an activity allows the user to edit its code and description, and also set whether the activity is active or not. A de-activated activity will be marked with a red dot as opposed to a green one and will not be available to select in the daily activities. Note that if an activity that is already in use on a well gets de-activated, it will be replaced with a blank activity in the daily activities. Clicking on the red trash bin icon to the right of each activity level will delete it.
Most activities are merely descriptive and can be added, removed, activated and de-activated at the user’s discretion. However, some activities special behaviour:
2J (Slide Drilling) and 2K (Rotary Drilling): Any code beginning with the number 2 will count as drilling and circulating time in the daily report and in KPI reports. They are also the only code apart from 3Z (Sidetrack) that allows the user to change the hole depth.
2J and 2K are the default activities for sliding and drilling which the slide sheet uses to automatically fill in the daily activities. It is important that these two codes are kept active and are not changed in any way.
Codes starting with ‘5’ and 10C: Codes that start with the number 5 are counted as circulating time in the daily report and in KPI reports. The exception to this rule is code 10c (reshoot surveys, cycle pumps, downlink tools), which also counts as circulating time.
Codes starting with ‘8’: Codes starting with the number 8 are counted as rig non-productive time (NPT).
Codes starting with ‘26’: Codes starting with the number 26 are counted as directional non-productive time (NPT).
Code 3Z (Sidetrack): The 3Z code allows the user to change the hole depth recorded in the daily activities without recording any drilling or circulating time. This is useful for activities such as pulling back to a sidetrack KOP.
The Phases page allows the user to define the drilling phases that are available to the selected operator. Phases are set in the daily activities as they are recorded the Daily Reporting. This then allows the user to separate the well into parts when viewing KPI reports and compare the performance of wells at similar stages of drilling. Using phases is optional but recommended.
Figure 92: Phases page
The user can add new phases using the edit menu, which is opened by clicking on the icon in the bottom right of the page and has the following functions:
Add: Adds a new phase to the list.
Refresh: Refreshes the page.
Each phase has an abbreviated code which is displayed in the daily activities and then a longer form description. Clicking on a phase allows the user to edit its code and description. Clicking on the red trash bin icon to the right of each phase level will delete it.
The Warnings page allows the user to set up the anti-collision warning levels. Warning levels in the Web Portal are based on separation factor ratio, which is calculated using the below formula:
Figure 93: Warnings page
The user can add new levels using the edit menu, which is opened by clicking on the icon in the bottom right of the page and has the following functions:
Add: Adds a new warning level to the list.
Refresh: Refreshes the page.
Each warning level in the list shows its name and the separation factor (SF) that will trigger it. Clicking on a warning allows the user to edit its name and separation factor. Clicking on the red trash bin icon to the right of each warning level will delete it.