Completion and intervention: architecture, barriers and handover

Completion architecture: function, element and interface

Treat a completion as a system of downhole tubulars and equipment enabling well operation. Start with functions: which intervals communicate with the well, where production travels and which spaces are separated. Naming a component does not describe its whole function. A packer can separate the annulus from the production conduit, but a symbol alone does not establish installation, compatibility or condition of a particular item.

Build three linked lists when reading a schematic. Identify components, map them to spaces and interfaces, and identify records supporting the installed configuration. Distinguish design intent, as-built documentation and current status. A modification after intervention may leave an older as-built drawing historically correct but insufficient for current configuration. A recent file date does not establish that modifications were incorporated and approved.

Depth needs a reference: measured depth, vertical depth and datum are different. Nominal outside size does not determine an assembly minimum internal passage. Request manufacturer documents and installed-configuration records for actual equipment. Separate component intended, component identified and function evidenced in the learning report. Do not complete unknown sections of a schematic by assumption. The next analytical step is a justified evidence request to the responsible specialist, not prescribing well work.

Walkthrough

Document-review example: a design lists a packer, but the installation record lacks its identity. Design intent is supported; installed configuration and condition remain unknown. This does not prove the packer is absent.

Independent task

Prepare a table for tubing, packer and the wellhead interface: function, identity, connected space, required record and unknowns. Do not invent dimensions or ratings.

Attempt in the interactive worksheet →

Barrier function and evidence of condition

Analyse a barrier function against a possible flow path, its source and receiving space. An equipment list does not automatically show which elements perform the function together or where an interface remains unverified. Map each claimed function to elements, evidence and verification limits. A bare good-condition label does not make the reasoning reproducible.

Separate installed configuration, qualification or test records, and subsequent monitoring. They answer different questions. A result belongs to a specified object, state and time. Modification after testing requires review of which earlier evidence still applies. Naming two elements does not establish independence: shared interfaces, supporting systems and potential common causes need separate consideration.

As a jurisdiction-specific example, Norwegian Havtil Activities Regulations section 85 addresses tested barriers, sufficient independence and documented status at well handover. This is Norwegian regulatory context, not a universal rule for every country or asset. This exercise neither reproduces NORSOK D-010 nor establishes compliance with it. Applicable requirements must be determined separately.

When records are absent, state evidence not provided. That means neither a successful test nor a demonstrated failure. Identify the precise conclusion left unresolved and the information that could support it.

Walkthrough

Reasoning example: two elements are listed but the test record covers only one. Evidence for the second and independence of the function remain unresolved. Do not count two verified barriers automatically.

Independent task

For the claim barrier verified, build a matrix: flow path, function, elements, verification record, tested boundary, limitations and current status. List possible shared dependencies separately without prescribing field tests.

Attempt in the interactive worksheet →

Test records and post-intervention handover

A test record is meaningful only with a description of what was tested. Review well and element identity, configuration, boundaries, date, method, observations, approved criteria and disposition. A signed cover sheet does not remove a mismatch between the tested element and the installed component identity. Check whether a later revision superseded the record.

Pressure-curve shape alone does not determine leak tightness. Measurement conditions, temperature behaviour, system volume, instrument resolution and isolation boundaries matter. This exercise supplies no universal test pressure, duration or allowable decline: those require an applicable programme and technical basis. Similar graphs also do not establish that identical objects were tested.

Post-intervention handover needs changes reconciled with the current schematic and condition evidence. Record installed modifications, unresolved questions, applicable restrictions and owners of further review. Do not convert absent information into an acceptable status. If only an earlier test is available, state its historical scope and explain why the current conclusion needs additional verification.

The learning output is a traceable document-review conclusion and evidence request. It is not authorisation to continue work, alter configuration or place a well into service.

Walkthrough

If the schematic shows a modified assembly while the record covers the former configuration, the earlier test does not automatically establish the new assembly condition. Retain it as historical evidence with a defined scope.

Independent task

Create a handover sheet covering current configuration, modifications, applicable evidence, limitations, unknowns and review owners. State what must be checked before relying on an earlier test record.

Attempt in the interactive worksheet →

Capstone: prepare an evidence-based well handover

This is a logical exercise with hypothetical document labels, not real well data. The packet includes a design drawing, installed-equipment list, test record for the former configuration and subsequent modification note. A reconciled current schematic and verification link to the modified interface are absent. A proposed conclusion states all functions verified.

Walkthrough

Work from claim to evidence: document → supported fact → limitation → additional request. The interactive learning cards expose the packet; it contains no technical measurements.

Independent task

Review every packet card. Write a corrected conclusion, gap matrix and evidence requests. Separate unknown status, documented inconsistency and demonstrated technical failure.

Attempt in the interactive worksheet →