Rolling Mill Bearing Feather Key Positioning

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Solution Overview

Problem

Existing rolling mill bearings experience fluctuations in rolling pressure force due to the arrangement of feather keys, leading to wider foundations and workshops, which is undesirable for space efficiency and rolling quality.

Innovation Solution

The roll neck design incorporates a circumferential step merging into a stepped area, with the feather key or its receiving groove positioned close to the Rötscher line for force transmission, allowing the key to extend radially and minimizing axial length, thereby eliminating pressure force fluctuations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If the feather key is arranged in the area of the rolling pressure force acting on the journal bush, then the roll design can be shorter, but fluctuations in the rolling pressure force occur

Engineering Contradiction:
Improveroll lengthVSAvoidrolling pressure force stability
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The feather key is extracted from the force-absorbing journal bush area and relocated to the non-force-absorbing head region of the roll neck. This separation removes the feather key from the rolling pressure force transmission path, eliminating fluctuations in the rolling pressure force while maintaining the structural integrity and compactness of the roll design.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If the feather key is arranged outside the area of the rolling pressure force, then fluctuations in rolling pressure force are eliminated, but the roll design becomes longer

Engineering Contradiction:
Improverolling pressure force stabilityVSAvoidroll length
Core Design Contradiction:
ReliabilityVSLength of moving object

Solution Approach 1:

The feather key is oriented radially rather than axially, changing its primary dimension from the axial direction to the radial direction. This dimensional change allows the feather key to be positioned in the head region outside the rolling pressure force area while minimizing the axial length increase, thus maintaining a compact roll design without compromising rolling pressure force stability.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Length of moving object

If multiple feather keys are arranged in the head region of the roll neck, then the roll design can be shorter axially, but the complexity of the structure increases

Engineering Contradiction:
Improveaxial length of roll neckVSAvoidfeather key arrangement complexity
Core Design Contradiction:
Length of moving objectVSDevice complexity

Solution Approach 1:

The roll neck is segmented into distinct functional regions: the head region for feather key arrangement and the journal bush region for force absorption. This segmentation allows the feather key to be positioned in the head region with radial orientation, achieving compact axial length while maintaining simple and clear structural organization without unnecessary complexity.

Inventive Principle:
Principle #1Segmentation

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 results in narrower roll stands, foundations, and workshops while maintaining high rolling quality without pressure force fluctuations, achieving significant space savings.

Implementation Method 1

the neck bushing 4 sits on the roll neck 2. It is secured against twisting relative to the roll neck 2 by means of a feather key 5, which engages in the roll neck 2 and in the neck bushing 4

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

between the neck bush and the bearing bush a load-bearing lubricating film is provided

Methodology Applied
Scientific EffectLubrication: Lubrication

Data Source

PatentEP2032866B1Bearing for rolling-mill rolls
Publication Date: 2018.04.11 SMS GROUP GMBH
  • EP2032866B1 patent drawingFigure 1

AI summary

A bearing for rolling-mill rolls which each have two roll journals (2), of which at least one carries a journal bush (4) in the axial direction at least in a certain region, said journal bush (4) being arranged in a rotationally locked manner via a feather key (5), wherein the journal bush (4) is enclosed by a bearing bush (6) held in an insert (7), and a load-bearing lubricating film is provided between the journal bush (4) and the bearing bush (6), wherein the feather key (5) is provided in a region of the roll journal (2) which lies outside the region of the roll compression force acting on the journal bush (4) and transmitted to the insert (7), is to be improved in such a way that the fluctuations in the roll compression force which are caused by the feather key or its locating slot are ruled out and the roll is nonetheless of very short construction, such that considerable savings are obtained through narrower foundations and narrower rolling mill halls and also narrower roll workshops. To this end, it is proposed that the feather key (5) or its locating slot (11) be arranged as close as possible to the Rötscher line (10) defining the outer region of the compression force transmission, and that the extent of the feather key (5) in the radial direction be greater than its extent in the axial direction.