Switchable Magnetic Filter for Downhole Fluid Sampling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Downhole fluid sampling instruments face contamination and measurement inaccuracies due to magnetic particles, which are difficult to remove and can saturate magnetic traps, leading to ineffective filtering.

Innovation Solution

A switchable magnetic filter using a wire mesh with conductor and soft magnetic material strands, which can be activated to filter magnetic particles and then cleaned by deactivating the filter and using a fluid to remove captured particles, preventing interference with sensor measurements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a magnetic filter is used to filter magnetic particles from downhole fluid, then magnetic particle contamination is reduced, but the filter becomes saturated over time and loses filtering effectiveness

Engineering Contradiction:
Improvemagnetic particle contaminationVSAvoidfiltering effectiveness
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The magnetic filter is designed with switchable magnetization capability, transitioning from a static filter to a dynamic system that can be activated and deactivated. The filter medium contains soft magnetic material that can be magnetized by applying a magnetic field and demagnetized by removing it, allowing the filter to be regenerated in-situ without manual intervention.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The filtering operation follows a periodic cycle: the magnetic filter is activated to capture magnetic particles during fluid flow, then deactivated to release and remove the captured particles through backflushing. This periodic activation and deactivation restores the filter's effectiveness, enabling continuous operation without permanent saturation.

Inventive Principle:
Principle #19Periodic action

2Object-affected harmful factors

If magnetic particles are captured by the filter, then contamination of the sample chamber is prevented, but the filter requires cleaning that interrupts continuous filtering

Engineering Contradiction:
Improvesample chamber contaminationVSAvoidcontinuous filtering
Core Design Contradiction:
Object-affected harmful factorsVSProductivity

Solution Approach 1:

The system maintains continuous protection of the sample chamber by using dual filters or rapid cycling between activation and deactivation states. While one filter is being cleaned, another continues filtering, or the same filter quickly transitions between states, ensuring uninterrupted protection of the measurement chamber.

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The magnetic filter performs self-cleaning through automated backflushing when deactivated. The control system automatically reverses fluid flow through the filter medium to remove captured particles without requiring manual disassembly or intervention, enabling the filter to service itself and maintain continuous operation.

Inventive Principle:
Principle #25Self-service

3Object-affected harmful factors

If a permanent magnetic filter is used, then magnetic particles are effectively trapped, but the filter cannot be cleaned and becomes ineffective over time

Engineering Contradiction:
Improvemagnetic particle trappingVSAvoidfilter cleaning
Core Design Contradiction:
Object-affected harmful factorsVSEase of repair

Solution Approach 1:

The magnetic properties of the filter medium are dynamically changed by applying or removing magnetic fields. The soft magnetic material in the filter can be magnetized to strong magnetization for particle capture, then demagnetized to release particles for cleaning. This parameter change enables the filter to switch between trapping and cleaning modes without physical modification.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The filter medium combines soft magnetic material with a porous substrate structure. The soft magnetic material provides controllable magnetization for particle capture, while the porous substrate allows fluid flow and particle release during backflushing. This composite structure enables both effective trapping and easy cleaning functions.

Inventive Principle:
Principle #40Composite materials

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

The switchable magnetic filter effectively minimizes magnetic particle contamination, allowing for accurate and precise measurements by periodically cleaning and reactivating the filter, maintaining its effectiveness over time.

Implementation Method 1

The switchable magnetic filter includes at least one wire mesh with strands of conductor and strands of soft magnetic material, switchable between a magnetic state producing a magnetic field and a non-magnetic state producing substantially no magnetic field

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

strands of soft magnetic material oriented in a second direction that is different from the first direction... when activated, filter magnetic particles from downhole fluid entering the sample chamber

Methodology Applied
Scientific EffectMagnetic attraction: Magnetism

Data Source

PatentEP3022387B1Switchable magnetic particle filter
Publication Date: 2018.03.28 BAKER HUGHES CO
  • EP3022387B1 patent drawingFigure 1
  • EP3022387B1 patent drawingFigure 2
  • EP3022387B1 patent drawingFigure 3

AI summary

Systems, devices and methods for strands of conductor oriented in a first direction; and strands of soft magnetic material oriented in a second direction that is different from the first direction evaluating a downhole fluid from a borehole intersecting an earth formation. The method may include filtering magnetic particles in the downhole fluid by activating a switchable magnetic filter when the downhole fluid enters a sample chamber in the borehole. The downhole fluid may include formation fluid. The filter may include a wire mesh comprising strands of conductor oriented in a first direction; and strands of soft magnetic material oriented in a second direction. The method may also include cleaning the switchable magnetic filter by deactivating the switchable magnetic filter. Cleaning the switchable magnetic filter may include removing filtered particles using a fluid. The fluid may be at least one of: i) the downhole fluid; and ii) engineered fluid. The method may further include estimating a parameter of interest of the downhole fluid in the sample chamber.