Surface-Pumped Dissolvent Clearing for Plugged Control Lines

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for clearing plugged control lines in surface-controlled sub-surface safety valves are costly, time-consuming, and require extensive resources, leading to reduced well functionality and safety risks.

Innovation Solution

An apparatus and method involving a dissolvent, such as acid, pumped through the control line at high pressure to chemically dissolve plugging material, connected upstream and operated from the surface without requiring additional downhole access, using a simple design with separate hydraulic and dissolvent pumps for safety.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional control line clearing methods are used, then the control line can be cleared, but the process is costly, time-consuming, and requires extensive resources including shutdown and special installation packages

Engineering Contradiction:
Improvecontrol line functionalityVSAvoidwell shutdown time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The invention extracts the clearing function from complex downhole operations and performs it from surface facilities. A pump is connected to the control line at surface level, and clearing fluid is pumped through the control line to dissolve plugging material, eliminating the need for well shutdown and complex downhole intervention equipment.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention introduces a clearing fluid as an intermediary substance that chemically dissolves the plugging material in the control line. This mediator enables the clearing function without requiring mechanical intervention or well shutdown, allowing the process to be performed from surface facilities.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If conventional control line clearing methods are used, then the control line can be cleared, but special installation packages and specially trained experts are required

Engineering Contradiction:
Improvecontrol line functionalityVSAvoidclearing operation complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts the clearing function from complex downhole operations and performs it from surface facilities. A pump is connected to the control line at surface level, and clearing fluid is pumped through the control line to dissolve plugging material, eliminating the need for well shutdown and complex downhole intervention equipment.

Inventive Principle:
Principle #2Taking out (Extraction)

3Reliability

If conventional control line clearing methods are used, then the control line can be cleared, but well production is drastically reduced

Engineering Contradiction:
Improvecontrol line functionalityVSAvoidwell production
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The invention enables continuous well operation during the control line clearing process. By performing the clearing from surface facilities using a pump connected to the control line, the well does not need to be shut down, allowing production to continue uninterrupted while the clearing operation is performed.

Inventive Principle:
Principle #20Continuity of useful action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Facilitates rapid restoration of control line functionality with minimal downtime and cost, reducing production loss by efficiently dissolving plugging material in minutes to days.

Implementation Method 1

a dissolvent, such as acid, pumped through the control line at high pressure to chemically dissolve plugging material

Methodology Applied
Scientific EffectChemical dissolution: Solvation

Implementation Method 2

a pumping means configured to pump a dissolvent through a connecting means into the control line to build up dissolvent pressure in the control line

Methodology Applied
Scientific EffectHydraulic pumping: Pump

Data Source

PatentEP3775480B1Apparatus for clearing a plugged control line
Publication Date: 2025.08.20 ADNOC
  • EP3775480B1 patent drawingFigure 1

AI summary

The present invention relates to an apparatus (20) for clearing a plugged control line (12), in particular for clearing a plugged surface controlled sub-surface safety valve (11) control line (12), the apparatus (20) comprising a connecting means (27) configured to connect the apparatus (20) to an upstream end of the plugged control line (12); and a pumping means (21, 22) configured to pump a dissolvent (30) through the connecting means (27) into the control line (12) to build up dissolvent pressure in the control line (12).The invention further comprises a bore system and a method for clearing a plugged control line (12).