Downhole Filter Flushing for Continuous Solids Separation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional drilling fluid filters become clogged, requiring removal from the wellbore for cleaning, leading to lost drilling time and increased wear on drilling motors due to solid particles bypassing the filter and entering sensitive equipment.

Innovation Solution

A downhole separation system that automatically flushes collected solids into the annulus around its outer surface, using a sliding assembly and pressure/flow rate controls to maintain operation without removing the filter, ensuring continuous drilling fluid filtration and preventing particle entry into drilling motors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional filters are used to remove solid particles from drilling fluid, then solid particle removal is improved, but the filter requires removal from the wellbore for cleaning causing lost drilling time

Engineering Contradiction:
Improvesolid particle removalVSAvoiddrilling time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The filter system performs self-cleaning by utilizing the existing drilling fluid flow to flush accumulated solid particles from the filter screen. The system includes a self-cleaning mechanism where drilling fluid flows through a bypass passage to remove collected solids from the filter screen, eliminating the need for manual intervention and maintaining continuous operation without removing the filter from the wellbore.

Inventive Principle:
Principle #25Self-service

2Reliability

If filters are removed from the wellbore for cleaning, then solid particle removal efficiency is maintained, but drilling operations must be stopped

Engineering Contradiction:
Improvefiltration efficiencyVSAvoiddrilling operations continuity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The filter system maintains continuous filtration operation by implementing an automatic self-cleaning mechanism. The drilling fluid continuously flows through both the filter screen for particle removal and a bypass passage that flushes accumulated solids from the screen. This dual-flow path ensures uninterrupted filtration and cleaning operations, maintaining both high filtration efficiency and continuous drilling productivity without requiring system removal or shutdown.

Inventive Principle:
Principle #20Continuity of useful action

3Productivity

If filters are left in place without cleaning, then drilling operations continue uninterrupted, but solid particles bypass the filter and enter drilling motors causing wear

Engineering Contradiction:
Improvedrilling operations continuityVSAvoiddrilling motor protection
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system utilizes hydraulic flow principles where drilling fluid is directed through a bypass passage that creates a flushing action on the filter screen. The fluid flow dynamics automatically remove accumulated solid particles from the screen surface and transport them away from the filter assembly. This hydraulic self-cleaning mechanism ensures continuous particle removal capability while maintaining uninterrupted drilling operations and protecting downstream drilling motors from particle damage.

Inventive Principle:
Principle #29Pneumatics and hydraulics

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

Enables continuous filtration and solid particle removal without stopping drilling operations, reducing wear on drilling motors and maintaining equipment efficiency by automatically adjusting to flow and pressure changes.

Implementation Method 1

a filter flow path within the housing extends through the plurality of openings of the screen for filtering at least a portion of any solids contained in a media flowing through the filter flow path

Methodology Applied
Scientific EffectFiltration: Filter (physical)

Implementation Method 2

a dampening mechanism including a fluid passage connecting two dampening chambers, wherein a fluid flow through the fluid passage slows the rate at which the activation mechanism moves between the default position and the activated position

Methodology Applied
Scientific EffectFluid resistance damping: Viscous Damping

Data Source

PatentEP4726171A2Downhole separation system and method
Publication Date: 2026.04.15 WORKOVER SOLUTIONS INC
  • EP4726171A2 patent drawingFigure 1~2
  • EP4726171A2 patent drawingFigure 3
  • EP4726171A2 patent drawingFigure 4

AI summary

A downhole separation system for use upstream of any tool through which a media flows. The separation system filters at least a portion of any solids from the media flowing through a filter flow path. The separation system flushes at least a portion of the filtered solids through a flush flow path, through a flush outlet on an outer surface of a housing, and into a space surrounding the housing. A screen and an activation mechanism are disposed within a housing inner bore. The filter flow path extends through a plurality of openings in the screen. The activation mechanism is configured to move between a default position in which it directs fluid through the filter flow path and an activated position in which it directs fluid through the flush flow path. Optionally, a spring within the housing inner bore is configured to bias the activation mechanism toward the default position.