Coring Tool Core Jam Indicator Mandrel Design

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing core jam indicators require high weight-on-bit for operation and apply undesirable hydraulic forces, making them unsuitable for coring operations with limited weight-on-bit, and often result in incomplete movement of components, leading to incomplete pressure signal generation.

Innovation Solution

A core jam indicator with a plug, anchor member, and mandrel that moves between deactivated and activated positions to impede or facilitate fluid flow, coupled to the inner barrel, where the mandrel's piston force acts over an area smaller than the inner barrel's maximum transverse cross-sectional area, reducing the required weight-on-bit and minimizing hydraulic forces on moveable components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If previously known mechanical core jam indicators are used, then core jam detection is provided through pressure signal generation, but high weight-on-bit is required for proper operation

Engineering Contradiction:

Improvecore jam detection reliabilityVSAvoidweight-on-bit requirement

Core Design Contradiction:

ReliabilityVSForce

Solution Approach 1:

The patent changes the design parameters of the core jam indicator by positioning the ball seat surface below the mandrel rather than above it. This parameter change fundamentally alters the force balance, allowing the indicator to operate with reduced weight-on-bit while maintaining reliable core jam detection capability through the same pressure signal generation mechanism.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If previously known mechanical core jam indicators are used, then core jam detection is provided, but undesirable hydraulic forces are applied to components

Engineering Contradiction:

Improvecore jam detection reliabilityVSAvoidhydraulic forces on components

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent inverts the traditional design by placing the ball seat surface below the mandrel instead of above it. This inversion reverses the direction of hydraulic force application, causing undesirable hydraulic forces to act on stationary components (housing) rather than moveable components (mandrel), thereby eliminating the counteracting effect that previously prevented complete component movement.

Inventive Principle:

Principle #13The other way round (Inversion)

3Reliability

If sufficient weight-on-bit is applied to move components in previously known indicators, then pressure signal generation occurs, but core samples may be damaged

Engineering Contradiction:

Improvepressure signal generationVSAvoiddamage to core samples

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

By changing the ball seat surface position to below the mandrel, the patent reduces the weight-on-bit requirement for component movement. This parameter change enables reliable pressure signal generation for core jam detection while using lower forces that do not damage the core sample, resolving the contradiction between detection reliability and core sample integrity.

Inventive Principle:

Principle #35Parameter changes

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 solution allows for reliable core jam detection with reduced weight-on-bit requirements and consistent operation, minimizing damage to core samples by generating a detectable pressure signal without applying excessive hydraulic forces.

Implementation Method 1

a piston force acting on the mandrel resulting from a pressure difference above and below the mandrel

Methodology Applied

Scientific EffectPressure difference: Pressure Gradient

Implementation Method 2

The mandrel at least partially covers the at least one fluid port of the plug in the activated position to impede fluid flow through the at least one fluid port

Methodology Applied

Scientific EffectFluid flow restriction: Pressure Gradient

Data Source

PatentUS10125559B2Core jam indicator for coring tools and coring tools including such core jam indicators

Publication Date: 2018.11.13 BAKER HUGHES CO

AI summary

Core jam indicators for use with coring tools include a plug coupled with an inner barrel and configured to selectively close the entrance of the inner barrel. The plug has at least one fluid port extending through a wall of the plug between an interior and an exterior of the plug. The mandrel at least partially covers the at least one fluid port of the plug in an activated position and the at least one fluid port is at least partially uncovered by the mandrel in a deactivated position. The mandrel is coupled to the inner barrel. A piston force acting on the mandrel resulting from a pressure difference above and below the mandrel acts over an area smaller than a maximum transverse cross-sectional area of the inner barrel. Coring tools include such core jam indicators. Components are provided and assembled to form such core jam indicators.