Creating iPTA Workflow
This workflow starts with an engineer analyzing an initial build-up and uploading the resulting Saphir document as a seed in K-A. The iPTA workflow extracts each new relevant shut-in and applies the same parameters and model as in the seed document. It is also possible to run an improve on some of the model parameters. See Incremental PTA (iPTA) for more details.
A Saphir file must be uploaded under the well. This file serves as the seed document for iPTA.
A Shut-in channel must exist for the well.
A corrected production must exist for the well.
Select a Saphir document in the field hierarchy and click on Incremental PTA,
, under the Info or Plot tab:
This will launch the following iPTA dialog:
Give the iPTA workflow some Name. This field is mandatory.
Select the seed PTA document to use for this iPTA (by default, it will be set to the Saphir document in step 1). Model parameters are extracted from this file.
Note
The document should contain a single analysis. User can clean the file inside KA (See Cleaning documents for more details)
If multiple gauges are present in the seed document, a warning will appear.
Select the Pressure and Corrected production channels to use for this iPTA.
Set the Save strategy and Workflow type.
Save strategy: There are two ways users can create/update Saphir files with new data:
Single document with one analysis per shut-in: any new data are sent to the PTA document defined in the iPTA creation wizard and a new analysis is created for each shut-in. A maximum of 10 analyses can be created in a single document, after which a new document will automatically be created.
One document per shut-in: Each shut-in is extracted in a new document. Data in each document are truncated at the extracted shut-in.
Workflow type: There are three types of iPTA workflows available:
Extraction only: This is the only available option if the selected PTA document does not contain a model. The data up to a given shut-in will be sent to the PTA Service which will perform the extraction.
Extraction with model: In addition to the steps explained in (1) above, the model in the PTA document is extended up to the shut-in being processed.
Extraction with model + improve: In addition to the steps explained in (2) above, if this option is selected, an improve strategy is requested by the user at the time of iPTA creation. The user can specify what model parameters to improve on, as well as their ranges. During execution, after the model has been extended to the processed shut-in, in improve on the loglog plot is performed.
Optional. By default, Update permeability Enabled by default for Extraction only workflow type. the iPTA workflow performs an automatic match. The IARF line is repositioned to the stabilization period and used to update the permeability value accordingly.
Optional. If the Auto-compute semilog PStar option is checked, a line will automatically be drawn on the semilog plot to compute P* using permeability stabilization and the corresponding diagnostic skin.
When the seed document includes full PVT data, the creation dialog offers the option to update Pref for each shut-in.
Note
By enabling the "Update each analysis" option, the following parameters can be adjusted:
Time offset.
Delta pressure.
The updated Pref is then calculated as: Pref = Pinput (P shut-in start + time offset) + delta pressure. This updated reference pressure (Pref) is then used to recompute the PVT parameters.
In the Shut-in requirements section:
Set the Minimum shut-in duration to process in this iPTA. Any valid shut-in shorter than this value will not be processed by the iPTA.
The workflow can be applied to a set of shut-ins grouped by type or category. These options allow filtering of all detected or validated shut-ins so that the iPTA only uses those falling within a specific type and category.
Note
Shutin Types: Shut-ins can be classified automatically if the Shut-in identification user task is applied using the choke channel.
This task classifies shut-ins as either hard or soft using a defined logic. For more details about the classification logic, it is recommended to refer to the Shut-In classification section.
Manual classification is also possible. See V#UUID-705bd155-9238-bf8b-2893-636676d943edalidating Shut-Ins or PTA Dashboard for more details.
Optional. Add a label(s) if necessary.
Note
This label(s) will be added to the iPTA instance, the generated documents, the associated well property container and the well properties in the container.
Select whether to Replicate results to Master container or not. If unchecked, the iPTA results will not be copied to the Master well properties container.
Click on Create.