Fluid Control Means Manufacturing Using Interference Fit

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for manufacturing fluid control means for valves, such as gate valves, face challenges with costly materials like brass or bronze, and the use of rubber coatings which can lead to corrosion and detachment, affecting the valve's operational reliability and longevity.

Innovation Solution

A method involving the formation of nuts and wedges from materials with different hardness levels, connected through expansion using a mandrel, ensuring a strong and cost-effective mechanical connection, with optional protrusions and tracks for enhanced stability, and a waterproof coating for protection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the entire wedge is formed in brass or bronze to ensure easy operation and prevent seizing, then the ease of operation is improved, but the manufacturing cost increases significantly

Engineering Contradiction:
Improveease of operationVSAvoidmanufacturing cost
Core Design Contradiction:
Ease of operationVSEase of manufacture

Solution Approach 1:

The wedge is divided into two separate parts: a wedge body made of cast iron and a nut made of brass or bronze. This segmentation allows each component to be manufactured from the most cost-effective material while maintaining the required functional properties, thereby reducing overall manufacturing cost while preserving ease of operation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention uses composite construction by combining two different materials (cast iron and brass/bronze) in a single assembly. The cast iron wedge body provides structural strength and cost-effectiveness, while the brass/bronze nut provides bearing suitability and prevents seizing, achieving a cost-effective solution with maintained operational ease.

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If a rubber coating is used to connect the brass nut and cast iron wedge to reduce manufacturing cost, then the manufacturing cost is reduced, but the reliability deteriorates due to loosening, corrosion, and detachment over time

Engineering Contradiction:
Improvemanufacturing costVSAvoidreliability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The harmful rubber coating intermediary is completely removed from the connection system. Instead, the invention uses a direct mechanical interference fit where the brass nut is pressed onto the cast iron wedge, eliminating the source of loosening, corrosion, and detachment problems while maintaining cost-effectiveness.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces the rubber coating intermediary with a direct metal-to-metal interference fit. The transition zone between the brass nut and cast iron wedge creates a mechanically interlocked connection that is more reliable than rubber bonding, while still being cost-effective to manufacture.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Strength

If the shaft is made from stainless steel to ensure sufficient life and strength, then the strength is improved, but the manufacturing cost increases

Engineering Contradiction:
ImprovestrengthVSAvoidmanufacturing cost
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

Stainless steel is used only for the shaft where high strength and corrosion resistance are critical for structural integrity and longevity. Other components like the wedge body use cast iron where sufficient, reducing overall material cost while maintaining necessary strength where required.

Inventive Principle:
Principle #3Local quality

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 method provides a durable, cost-effective, and reliable connection between the nut and wedge, reducing the risk of corrosion and detachment, while ensuring the valve's operational efficiency and longevity.

Implementation Method 1

connecting the two parts by expanding the nut means by means of mandrel means

Methodology Applied
Scientific EffectMechanical expansion: Deformation

Implementation Method 2

a waterproof coating for protection

Methodology Applied
Scientific EffectCorrosion protection: Coatings

Data Source

PatentEP3362712B1A method for manufacturing fluid control means
Publication Date: 2020.01.15 AVK HLDG AS
  • EP3362712B1 patent drawingFigure 1~2
  • EP3362712B1 patent drawingFigure 3~4
  • EP3362712B1 patent drawingFigure 5~10

AI summary

Disclosed is a method for manufacturing fluid control means (2) for controlling a fluid flow through a valve (1). The method comprises the steps of forming nut means (5) with an inner through hole (6), wherein the nut means (5) are primarily made from a first material, forming wedge means (9) with a nut cavity (10), wherein the wedge means (9) are primarily made from a second material and wherein the first material is harder than the second material or the second material is harder than the first material, arranging the nut means (5) inside the nut cavity (10), and connecting the nut means (5) and wedge means (9) by expanding the nut means (5) and/or contracting the wedge means (9) to make the nut means (5) and the wedge means (9) engage each other.