Carbon Thrust Bearing Segments With Forged Uniform Grain Structure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional manufacturing processes for carbon thrust bearing segments are time-consuming, expensive, and result in poor mechanical and physical properties, with high defect rates and inefficient use of resources.

Innovation Solution

A process using stainless steel round bars/sheets, involving induction heating, hot forging, stress relieving, hardening, tempering, and surface finishing to achieve exceptional strength, hardness, ductility, and uniform grain structure, reducing processing steps and costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional manufacturing process (wax injection, clusters assembly, slurry coating, stuccoing, de-waxing, backing, molten metal preparation, casting, knockout, cutting off, gates grinding, shot blasting, heat treatment) is used, then segments can be produced from raw materials, but production time is excessive (4-5 weeks) and cost is high

Engineering Contradiction:
Improveproduction timeVSAvoidmanufacturing cycle time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent extracts and eliminates unnecessary intermediate processing steps from the conventional manufacturing process. Specifically, it removes wax injection, clusters assembly, slurry coating, stuccoing, de-waxing, backing, and multiple heat treatment steps, retaining only the essential operations: molten metal preparation, casting, knockout, cutting off, gates grinding, and shot blasting. This extraction of redundant steps directly reduces production time from 4-5 weeks to a significantly shorter cycle.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies the skipping principle by rushing through the manufacturing process with minimized intermediate steps. Instead of following the conventional sequence with multiple prolonged operations, the process skips directly from molten metal preparation to casting, then rapidly proceeds through knockout, cutting, grinding, and shot blasting in a streamlined sequence, eliminating waiting times and redundant operations.

Inventive Principle:
Principle #21Skipping (Rushing through)

2Strength

If conventional manufacturing process is used, then segments can be produced, but mechanical and physical properties (strength, hardness, ductility, toughness, uniform grain structure) are poor

Engineering Contradiction:
Improvemechanical propertiesVSAvoidgrain structure uniformity
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by carefully preparing the molten metal with precise compositional control before casting. The molten metal is prepared with specific alloying elements and controlled chemistry to ensure optimal microstructure formation during casting. This preliminary preparation of the molten metal with controlled composition and temperature directly influences the grain structure uniformity and mechanical properties of the final segments.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes critical parameters including molten metal composition, casting temperature, and cooling rate to optimize mechanical properties. By adjusting the chemical composition of the molten metal and controlling the thermal parameters during casting and subsequent heat treatment, the process achieves improved strength, hardness, ductility, toughness, and uniform grain structure compared to conventional methods.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If conventional manufacturing process is used, then segments can be produced, but defect rate is high (20-30% rejection due to blow holes, surface impurities, bending, pin holes)

Engineering Contradiction:
Improvedefect rateVSAvoidmanufacturing defects
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent converts potential harmful factors into benefits by using controlled molten metal preparation techniques that prevent defect formation. The controlled pouring and casting process transforms what could be sources of defects (molten metal handling) into a controlled process that eliminates blow holes and pin holes. The simplified process without wax patterns and clusters eliminates the source of many surface impurities and bending defects.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent extracts and removes the sources of manufacturing defects by eliminating wax injection, clusters assembly, and multiple coating steps that inherently introduce surface impurities, blow holes, and bending defects. By removing these intermediate steps and proceeding directly from molten metal preparation to casting, the process eliminates the primary sources of the 20-30% rejection rate associated with conventional methods.

Inventive Principle:
Principle #2Taking out (Extraction)

4Ease of manufacture

If conventional manufacturing process is used, then segments can be produced, but cost is high due to skilled labor requirements and expensive infrastructure

Engineering Contradiction:
Improvemanufacturing costVSAvoidprocess complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The patent extracts and eliminates the complex intermediate processing steps that require skilled labor and expensive infrastructure. By removing wax injection equipment, cluster assembly fixtures, slurry coating facilities, stuccoing equipment, and multiple heat treatment furnaces, the process dramatically reduces infrastructure costs and labor skill requirements while maintaining segment quality through streamlined casting and finishing operations.

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

The process significantly reduces production time, defect rates, and costs while enhancing mechanical and physical properties, resulting in segments with improved strength, hardness, ductility, and uniform grain structure.

Implementation Method 1

The billets are heated in induction furnace at 900°C-1000°C

Methodology Applied
Scientific EffectInduction heating: Induction Heating

Implementation Method 2

the segment is subjected to heat treatment process i.e. stress relieving, hardening and tempering process

Methodology Applied
Scientific EffectStress relieving heat treatment: Heat Treatment

Implementation Method 3

hardening and tempering process successively for obtaining predetermined mechanical properties

Methodology Applied
Scientific EffectHardening: Heat Treatment

Data Source

PatentEP3630387B1A process of manufacturing of segments for carbon thrust bearing
Publication Date: 2024.08.28 SARADVA ATULKUMAR RAGHAVJIBHAI
  • EP3630387B1 patent drawingFigure 1
  • EP3630387B1 patent drawingFigure 2
  • EP3630387B1 patent drawingFigure 3

AI summary

A process of manufacturing of segment for carbon thrust bearing uses stainless-steel (SS) round bars/sheets/logs of suitable grade as raw material. The SS round bars/sheets/logs undergo cutting operation to cut into SS billets. The billets successively undergo heating and hot forging processes to form segments of desired shapes. Thereafter, the segment is subjected to heat treatment process i.e. stress relieving, hardening and tempering process successively for obtaining consistent and uniform grain structure, mechanical properties and physical properties of segments which are cost-effective in terms of lower maintenance and lower handling efforts. After heat-treatment process, segment undergoes surface-finishing processes i.e. grinding, lapping and polishing successively for obtaining mirror like surface finishing that gives greater anti-friction property and lower co-efficient of friction. The manufacturing process according to present invention yields consistent grain structure, refine, dense and uniform microstructure of segments which imparts optimum strength, ductility, toughness and resistance to impact and fatigue.