Adhesive Bonded Casting Hole Plugs for Heat Exchangers

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing methods for closing off casting holes in heat exchangers are expensive, labor-intensive, and prone to leaking, as they require machining and the use of screws and sealants, which can damage the heat exchanger and lead to sealing issues.

Innovation Solution

A plug with an internal passage for a glue or bonding agent is used to close off casting holes in heat exchangers, eliminating the need for machining and providing a secure seal without the use of screws, by being glued or bonded into place, reducing manufacturing costs and preventing damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional screw plugs with seals and sealants are used to close casting holes, then the casting holes can be sealed, but the manufacturing process becomes expensive and labor-intensive requiring high finish machining and internal screw threads

Engineering Contradiction:
Improvesealing reliabilityVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent replaces the mechanical screw-threaded connection system with a chemical bonding system. The plug is bonded to the casting hole using adhesive or epoxy resin, eliminating the need for machining screw threads, drilling precision holes, and installing complex seal assemblies. This substitution dramatically simplifies the manufacturing process while maintaining sealing reliability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent extracts and removes the complex sealing components (screw threads, seals, sealants, shoulders) from the traditional plug design. The simplified plug consists essentially of a bonding surface that attaches directly to the casting hole wall through adhesive bonding, taking out all the unnecessary mechanical sealing elements that complicated the manufacturing process.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If high finish machining is performed on casting holes to accommodate traditional plugs, then proper sealing can be achieved, but the risk of damage to the heat exchanger increases

Engineering Contradiction:
Improvesealing qualityVSAvoiddamage risk to heat exchanger
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces mechanical machining operations (drilling, reaming, threading) with a chemical bonding process. The plug is attached using adhesive that can bond to the as-cast surface or lightly prepared surface, eliminating the need for aggressive machining that risks damaging the thin-walled heat exchanger structure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the bonding mechanism from mechanical interlocking (requiring high finish surfaces) to chemical adhesion (which can work on rougher, as-cast surfaces). This parameter change in the bonding approach allows attachment without the harmful high-finish machining operations that could damage the heat exchanger.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If traditional plug methods with multiple components are used, then casting holes can be closed, but the process becomes time-consuming and costly

Engineering Contradiction:
Improvesealing effectivenessVSAvoidmanufacturing efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent merges multiple separate components (plug body, seal elements, screw threads, sealant application components) into a single integrated bonding surface. The plug is designed with a surface specifically optimized for adhesive bonding, combining the sealing and attachment functions into one simple component that can be installed in a single operation.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent extracts and eliminates the multiple time-consuming steps of machining screw threads, installing seals, applying sealants, and tightening screws. The simplified process involves only attaching the bonded plug to the casting hole, taking out all the intermediate steps that reduced manufacturing efficiency.

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 solution reduces manufacturing costs, minimizes the risk of damage to the heat exchanger, and provides a reliable seal that is easy to maintain or repair, as the plug can be easily removed and replaced.

Implementation Method 1

A plug for closing off a casting hole in a product such as a heat exchanger, characterised in that the plug is provided with an internal passage for a glue or bonding agent

Methodology Applied
Scientific EffectAdhesive bonding: Adhesive

Data Source

PatentEP2486995B1Cast light metal products, such as a heat exchanger, with casting hole plugs, plug and method for manufacturing the same
Publication Date: 2020.08.05 DEJATECH HLDG
  • EP2486995B1 patent drawingFigure 1~3
  • EP2486995B1 patent drawingFigure 4~5
  • EP2486995B1 patent drawingFigure 6

AI summary

The invention relates to a product, at least partly cast from metal, comprising at least one casting hole, closed off by a plug, wherein the plug is glued or bonded into the casting hole, glue or bonding agent providing or aiding at least part of a seal sealing off the casting hole.