Magnetic Plug Mandrel Connection for Hot Rolling Mill Maintenance

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Solution Overview

Problem

The existing methods for exchanging plugs with respect to mandrels in hot rolling mills are complex and time-consuming, leading to difficulties in maintenance and reduced production efficiency due to potential failures in thread engagement.

Innovation Solution

The use of a magnetic connection member, such as a permanent magnet, between the plug and mandrel allows for easy detachment and attachment, ensuring the plug and mandrel remain coaxial and preventing thread engagement failures, facilitating easier maintenance and exchange.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the plug and mandrel are connected by screw threads, then the connection is strong and reliable, but the exchange process becomes complex and time-consuming due to potential thread engagement failures

Engineering Contradiction:

Improveconnection strengthVSAvoidexchange time

Core Design Contradiction:

StrengthVSLoss of time

Solution Approach 1:

The patent replaces the screw thread mechanical connection system with a magnetic field-based connection system. The mandrel includes a magnetic body at its tip, and the plug includes a magnetic body at its rear end, enabling magnetic attraction to hold the plug on the mandrel. This substitution eliminates thread engagement issues while maintaining strong connection and enabling quick exchange by simply pulling the plug off the mandrel.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a magnetic body as an intermediary between the mandrel and plug to achieve connection. Instead of direct mechanical threading, the magnetic bodies on both components create a magnetic field that acts as an intermediary force to hold the plug securely on the mandrel during operation while allowing easy removal when needed.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the plug is rotated and moved back and forth to detect suitable rotating angle and position, then thread engagement failure is avoided, but the exchange work becomes complicated and exchange time is lengthened

Engineering Contradiction:

Improvethread engagement reliabilityVSAvoidexchange operation simplicity

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent replaces the mechanical screw thread system requiring rotation and position detection with a magnetic field-based system. The magnetic attraction automatically guides the plug to the correct position on the mandrel without requiring manual rotation or complex detection procedures, simplifying the exchange operation while ensuring reliable connection.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If the plug and mandrel are not disposed to be coaxial during rotation, then a failure in engagement between threads occurs, but ensuring coaxial alignment increases the complexity of the exchange process

Engineering Contradiction:

Improvethread engagement reliabilityVSAvoidexchange process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical thread engagement system with a magnetic field-based connection system. The magnetic attraction between the magnetic bodies on the mandrel and plug automatically ensures coaxial alignment during connection, eliminating the need for complex alignment procedures or devices while maintaining reliable engagement.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

4Manufacturing precision

If the plug is exchanged frequently to prevent inner surface scratches, then product quality is maintained, but production efficiency is reduced due to complex exchange procedures

Engineering Contradiction:

Improveinner surface qualityVSAvoidproduction efficiency

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The patent replaces the complex mechanical thread-based connection system with a simple magnetic field-based system, enabling rapid plug exchange. This allows frequent replacement of worn plugs to prevent inner surface scratches and maintain product quality without significantly reducing production efficiency, as the magnetic connection allows plugs to be quickly attached and removed.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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

This configuration simplifies the exchange process, reduces maintenance time, and prevents damage to the joint portions, thereby enhancing production efficiency and ease of maintenance.

Implementation Method 1

a connection member which connects the plug and the mandrel by a magnetic force, in which the connection member is a permanent magnet

Methodology Applied

Scientific EffectMagnetic force: Magnetism

Data Source

PatentUS9486845B2Inner surface regulation tool, plug, mandrel, hot rolling mill, press piercing machine, and drawing machine

Publication Date: 2016.11.08 NIPPON STEEL CORPORATION

AI summary

An inner surface regulation tool includes a mandrel, a plug which is detachably connected to the mandrel, and a connection member which connects the plug and the mandrel by a magnetic force. One of the plug and the mandrel includes a column-shaped portion which extends in an axial direction of the one, and the other of the plug and the mandrel includes a joining hole which extends in an axial direction of the other and into which the column-shaped portion is inserted. In addition, the connection member is a permanent magnet which is attached to at least one of the column-shaped portion and the joining hole.