Cooled Wire Deposition Nozzle for High-Power Laser Metal Additive

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing laser metal wire deposition process is hindered by the frequent melting of the nozzle tip, leading to interruptions, reduced deposition rate, and increased costs due to frequent nozzle replacements, which contradicts the trend of increasing manufacturing efficiency by enhancing deposition rates.

Innovation Solution

The implementation of a cooling system for the nozzle, utilizing a metal block as a heat sink with a rear cooling portion and a coolant circuit to absorb and dissipate heat, thereby preventing significant melting and extending the nozzle's operational life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the laser power is increased to enhance deposition rate, then the productivity is improved, but the nozzle tip melts faster leading to more frequent interruptions

Engineering Contradiction:
Improvedeposition rateVSAvoidnozzle operational continuity
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

A cooling circuit is introduced as an intermediary system between the nozzle and the heat source. The cooling circuit circulates coolant through channels in the nozzle body, acting as a mediator to remove excess heat from the nozzle tip while allowing the high-power laser to continue operating. This enables the nozzle to withstand higher laser powers without melting, thus resolving the contradiction between increased productivity and maintained reliability.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If the deposition process is run continuously without interruption, then the productivity is improved, but the nozzle tip accumulates heat leading to melting

Engineering Contradiction:
Improvecontinuous operation timeVSAvoidnozzle tip temperature
Core Design Contradiction:
ProductivityVSTemperature

Solution Approach 1:

The cooling circuit enables continuous operation of the deposition process by providing ongoing heat removal. The coolant continuously circulates through the nozzle, maintaining thermal balance during extended operation. This allows the useful action (deposition) to continue without interruption while preventing the harmful accumulation of heat at the nozzle tip, thus resolving the contradiction between continuous operation and temperature control.

Inventive Principle:
Principle #20Continuity of useful action

3Manufacturing precision

If the nozzle is replaced frequently to maintain deposition quality, then the manufacturing precision is improved, but the loss of time increases

Engineering Contradiction:
Improvedeposition qualityVSAvoidnozzle replacement time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The cooling circuit is installed in advance in the nozzle design, performing preliminary protection against heat accumulation. By pre-equipping the nozzle with active cooling capability, the system prevents the condition that would lead to nozzle failure and subsequent replacement. This preliminary protective action eliminates the need for frequent nozzle replacements, thus maintaining deposition quality while avoiding the time loss associated with replacement operations.

Inventive Principle:
Principle #10Preliminary action

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 allows for continuous operation exceeding ten hours without nozzle replacement, enabling faster deposition rates and reducing costs by maintaining productivity and extending nozzle lifespan, while also allowing for increased laser power usage.

Implementation Method 1

a cooling system for the nozzle, utilizing a metal block as a heat sink with a rear cooling portion and a coolant circuit to absorb and dissipate heat

Methodology Applied
Scientific EffectHeat dissipation: Convection

Implementation Method 2

utilizing a metal block as a heat sink with a rear cooling portion and a coolant circuit to absorb and dissipate heat

Methodology Applied
Scientific EffectHeat sink: Heat Sink

Data Source

PatentEP3571002B1Wire dispenser for a laser metal wire deposition machine with a cooling circuit ; corresponding laser metal wire deposition machine ; method of performing laser metal wire deposition on a workpiece with such wire dispenser
Publication Date: 2022.03.09 GKN AEROSPACE SWEDEN AB
  • EP3571002B1 patent drawingFigure 1A
  • EP3571002B1 patent drawingFigure 1B~1C
  • EP3571002B1 patent drawingFigure 2

AI summary

A wire dispenser (9) for a laser metal wire deposition machine comprises a longitudinal duct (8) for guiding a wire (4A, 4B) from a proximal end (81) to a distal end (82) of the duct (8). A nozzle unit (6) is connected to the distal end (82) of the duct (8) and has a through bore (51) for receiving the wire (4B) from the distal end (82) of the duct (8) and for discharging the wire (4B) adjacent to a laser metal wire deposition site (16). The nozzle unit (6) includes a cooling circuit (771) for a cooling liquid.