Offset Wells

Offset Wells Section

Well Planning Report

The Offset Wells section allows for the manual selection of Events from Offset Wells selected for performance comparisons with the current planned Well. These Events are used to review Offset Well performance data which is used to determine the "Best Case" Offset Well performance and Technical Limit for the current planned operation from historical Wells contained in the EDM™ database.

This section uses Detail Spreadsheets to display Offset Well Event information. Each Offset Well Event will display detailed performance breakdown in a subsidiary display.

For information on using spreadsheets, see the Using Spreadsheets and Tables topic.

The Offset Wells section contains two spreadsheets:

Offset Wells - summary performance information for the selected Event
Offset Well Activity Summary - detailed performance information for each phase of the selected Event

Click the Select Offset Wells/Events button in the Offset Wells spreadsheet area to select Offset wells/events to populate both spreadsheets with data. The Select Offset Wells/Event dialog appears. The well planner can use this dialog to select Events.

Offset Wells Spreadsheet

This read-only spreadsheet lists the Wells selected in the Select Offset Wells/Events dialog. The Offset wells list provides the engineer with a summary interface that details the performance of each selected Offset well. For each Event in each Offset well, Total Duration, Technical Limit Duration, NPT Duration, NPT Percent, Invisible Lost Time, and Average Progress (Avg Rate) are displayed.

Prior to well construction, target times for each operation program step should be defined and saved in the Planned Operations section of the Well Planning report. The offset well performance results is then used to help the well planner determine performance for the planned Well.

A detailed record of actual performance is maintained in the Time Summary section of the Daily Operations report for each program step during execution. The actual operations are linked to planned operations, allowing for planned vs. actual comparisons.

Select Offset Wells/Events Button

Click the Select Offset Wells/Events button to select Offset Wells/Events to add to the spreadsheet. For information on using this button, see the Select Offset Wells/Events dialog topic.

Name

This column displays the Legal Name of the Offset Well.

Event

This column displays the Event Code of the Offset Well's Event.

Duration

This column contains the sum of all activity duration that are productive for the Offset Well/Event (NPT Level = 0 in the Time Summary section of the Daily Operations reports).

Technical Limit Duration (TLD)

This column contains the best performing phase/well for all planned phases of the Offset Well. The Technical Limit Duration is taken from the Planned Operations section of the Well Planning report for the Offset Well/Event.

Non-Productive Time Duration (NPT)

This column contains the total time of activities that are flagged as non-productive for the Offset Well/Event (NPT Level > 0 in the Time Summary section of the Daily Operations reports).

Non-Productive Time Percentage (NPT) %

This column contains the total percentage of non-productive time against total time for the Offset Well/Event.

Target

This column contains Target Duration of the Offset Well entered in the Planned Operations section of the Well Planning report. This value is the sum of all phases that have both planned and actual time recorded in the Offset Well.

Net Time

This column represents the total time for the Offset Well spent performing planned activity. This value is used to calculate Net Rate.

Net Time = Duration - NPT

Invisible Lost Time (ILT)

For each activity, when the target time is not achieved, the magnitude of the time gap is identified as Invisible Lost Time (ILT). Essentially, it is the time spent under-performing accounting for targets times and NPT.

ILT = Actual Time -Target Time - Non-Productive Time

A positive value represents extra time spent on an activity against planned time. A negative value occurs when the actual activity performed better than the planned activity.

Hole Length

The Hole Length calculation is based on value of the NPT Length Calculation system setting. When NPT Length Calculation is set to:

HOLE-SECTION - the depths used in calculating Technical Limits are taken from the Hole Sections area as follows:

For the Casing Phase, the value entered in the Last/Casing Liner MD Shoe field (CD_HOLE_SECT_GROUP.md_casing_bottom) is taken by the Well Planning Report Offset Wells spreadsheet as the Hole Length.

For the Drilling Phase, the difference between the Hole Section MD Top and MD Base (CD_HOLE_SECT_GROUP.md_hole_sect_base and md_hole_sect_top) is taken by the Well Planning Report Offset Wells spreadsheet as the Hole Length.

ACTIVITY - the Hole Length is calculated based on the measured depth range of the Casing or Drilling phase entered in the Time Summary section, for the Offset Well/Event.

For more information see the NPT Length Calculation System Setting topic in the EDM Administration Utility online help.

Avg Rate

Average Rate = Hole Length / Total Duration

Net Rate

Net Rate = Hole Length / Net Time

Offset Well Activity Summary Spreadsheet

This read-only spreadsheet enables the engineer to review detailed operations performance of the selected Offset Well. When an Offset Well is added, this spreadsheet is automatically populated with operations performance information for each Phase based on the Offset Well's planned and actual activities.

Calculate Values Button

The Phase information located in the Offset Well Activity Summary spreadsheet is not updated when data is changed in the originating Daily Operations reports. If there is a need to reload and calculate this data, click the Calculate Values button. This action will recalculate the spreadsheet using data currently existing in the Time Summary section of the Daily Operation reports for Offset Wells.

Caution: When this button is selected, a dialog appears prompting the user to indicate if they want to recalculate the Technical Limit ROP, Average Offset ROP, Technical Limit duration and Average Offset Duration fields in the Planned Operations section. Selecting Yes for this dialog will overwrite manually entered values in the Planned Operations section. For more information, see the Calculate ROP/Duration From Offsets Button.

Phase

Phase codes are used to determine the type of activity operations data is being entered against. The OpenWells administrator can enter

Hole Length

The Hole Length calculation is based on value of the NPT Length Calculation system setting. When NPT Length Calculation is set to:

HOLE-SECTION - the depths used in calculating Technical Limits are taken from the Hole Sections area as follows:

ACTIVITY - the Hole Length is calculated based on the measured depth range of the Casing or Drilling phase entered in the Time Summary section, for the Offset Well/Event.