Mill Liner Bolt Retention for External Shell Fastening

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Solution Overview

Problem

The current method of securing mill liners inside grinding mills poses significant hazards to operators due to confined spaces, uneven floors, poor visibility, falling objects, hot and humid conditions, and proximity to machinery, requiring them to work at heights and in close proximity to suspended loads.

Innovation Solution

A method and system where a mounting bolt is retained within the mill liner, allowing an extraction tool to be coupled from outside the mill to detach and pull the bolt through the mill shell, enabling secure fastening of the liner without the operator needing to enter the mill, using various attachment means like adhesives, magnets, and mechanical engagement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If operators manually install bolts inside the mill to secure liners, then the liner can be attached to the mill shell, but operators are exposed to hazardous conditions including confined spaces, falling objects, and proximity to machinery

Engineering Contradiction:
Improveliner attachment reliabilityVSAvoidoperator safety hazards
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The bolt installation operation is extracted from the confined mill interior and performed from the exterior. The extraction tool is inserted through the mill shell opening to engage and manipulate the bolt, allowing the operator to remain outside the hazardous confined space while completing the fastening operation

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The extraction tool serves as an intermediary device that transmits the operator's actions from the safe exterior environment to the bolt inside the mill. The tool includes a connector that engages the bolt head and a shaft that transmits mechanical force to install or remove the bolt without direct operator contact

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of manufacture

If operators work inside the mill to install liners, then proper fastening can be achieved, but visibility is poor and communication is difficult

Engineering Contradiction:
Improveliner installation feasibilityVSAvoidvisibility inside mill
Core Design Contradiction:
Ease of manufactureVSIllumination intensity

Solution Approach 1:

The installation operation is extracted from the poorly lit mill interior to the well-lit exterior environment. The operator performs all manipulation of the extraction tool and bolt from outside the mill where proper lighting and visibility conditions exist, eliminating the visibility constraints of working inside

Inventive Principle:
Principle #2Taking out (Extraction)

3Ease of operation

If the mounting bolt is inserted through the liner from the inside, then the liner can be secured, but the operator must climb up the mill shell and work at heights

Engineering Contradiction:
Improveliner fastening capabilityVSAvoidworking at heights hazard
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The traditional sequence is inverted: instead of inserting the bolt from the inside and securing it from within, the bolt is inserted from the outside through the mill shell opening, and the nut is secured from the exterior. This reverses the operator's position from hazardous interior/high-altitude work to safe exterior ground-level work

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The entire fastening operation is extracted from the mill interior to the exterior environment. The operator remains outside the mill throughout the process, manipulating the bolt and nut from the exterior where there are no height-related hazards

Inventive Principle:
Principle #2Taking out (Extraction)

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 approach enhances safety by removing the operator from hazardous conditions, simplifying the installation process, and reducing exposure to risks associated with working inside the mill.

Implementation Method 1

a biasing member interposed between the bolt housing and the outer housing and operable to urge the mounting bolt from a retracted position to an extended position

Methodology Applied
Scientific EffectElastic potential energy: Spring

Implementation Method 2

attaching the mounting bolt to the liner using at least one of: a) an adhesive

Methodology Applied
Scientific EffectAdhesive bonding: Adhesive

Implementation Method 3

attaching the mounting bolt to the liner using at least one of: b) magnets

Methodology Applied
Scientific EffectMagnetic attraction: Magnetism

Data Source

PatentEP3554711B1Mill liner installation
Publication Date: 2022.01.05 RUSSELL MINERAL EQUIPMENT PTY LTD
  • EP3554711B1 patent drawingFigure 1A
  • EP3554711B1 patent drawingFigure 1B
  • EP3554711B1 patent drawingFigure 2A~2B

AI summary

The present disclosure relates to a method for use in installation of a mill liner, the method including (a) retaining a mounting bolt at least partially within a liner opening extending through the mill liner, (b) positioning the mill liner against a mill shell so that the retained mounting bolt is aligned with a mill shell opening extending through the mill shell, (c) selectively coupling an extraction tool to the mounting bolt, the coupling performed by an operator outside of the mill shell, (d) detaching the mounting bolt from the liner using the extraction tool; (e) pulling the mounting bolt through the mill shell opening so that at least a portion of the mounting bolt protrudes outside of the mill shell, and, (e) securing a fastener onto the mounting bolt to thereby attach the mill liner to the mill.