Pulsed Liquid Jet Coating Removal Method
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for surface stripping using high-pressure liquid jets are energy-intensive and costly due to continuous operation and the need for abrasive addition, which increases energy consumption and disposal costs, and can cause unwanted damage to the workpiece surface.
Innovation Solution
A method utilizing a compression unit to generate a pulsed liquid jet with a nozzle equipped with an interrupter unit, allowing precise control over the liquid jet's flow, which is moved relative to the workpiece at optimized angles and frequencies to effectively remove firmly adhering coatings without continuous energy consumption and abrasive use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a continuous high-pressure liquid jet is used for stripping coatings, then the coating removal effect is achieved, but energy consumption increases significantly
Solution Approach 1:
The patent applies periodic action by using pulsed liquid jet instead of continuous jet. The liquid jet is delivered in periodic pulses with controlled duration and frequency, allowing the coating to be removed effectively while the liquid flows laterally between pulses. This periodic delivery reduces energy consumption by up to a factor of 20 compared to continuous operation, while maintaining effective coating removal capability.
2Productivity
If abrasives are added to enhance the water jet effect, then coating removal efficiency improves, but system complexity and disposal costs increase
Solution Approach 1:
The patent extracts the abrasives from the system entirely, using pure liquid jet pulses instead. By removing the abrasives component, the system becomes simpler without filtration requirements, and disposal costs are eliminated. The pulsed liquid jet alone achieves effective coating removal through lateral flow and concentrated impact, making the addition of abrasives unnecessary.
3Manufacturing precision
If continuous liquid jet is used, then coating removal is achieved, but cavitation occurs causing damage to the workpiece surface
Solution Approach 1:
The periodic pulsed delivery allows the liquid to flow laterally between pulses rather than accumulating on the surface. This prevents the liquid layer formation that leads to cavitation during continuous jet operation. The workpiece surface remains dry between pulses, eliminating the cavitation mechanism that causes unwanted damage to the underlying substrate.
4Manufacturing precision
If high pressure is applied continuously, then firmly adhering coatings are removed, but operating costs increase
Solution Approach 1:
The patent uses periodic high-pressure pulses instead of continuous high pressure. The compressed liquid is stored in a pressure chamber and released in controlled pulses, maintaining high pressure during each pulse for effective coating removal while allowing pressure to drop between pulses. This reduces energy consumption and operating costs by up to 95% compared to continuous high-pressure operation.
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 pulsed liquid jet method reduces energy consumption by up to a factor of 20, achieves precise removal of hard and firmly adhering coatings like metal and ceramic layers without damaging the workpiece, and eliminates cavitation risks, offering better quality and efficiency compared to continuous jet stripping.
Implementation Method 1
a compressor unit (3) which compresses a liquid to generate a liquid jet
Implementation Method 2
The pulsed liquid jet shatters the coating, while the underlying workpiece remains undamaged
Data Source
Figure 1~2
Figure 3~4
AI summary
Method for removing a surface layer from a workpiece (15) by a liquid jet, using a compressor unit (3), which compresses a liquid to produce a liquid jet, and using a nozzle (10), which is connected to the compressor unit (3) and has an outlet opening (11), through which the compressed liquid leaves in the form of a liquid jet (14). It also involves using an interrupter unit (8), which can interrupt or allow a flow of the compressed liquid to the outlet opening (11), wherein the following method steps are carried out: - compressing the liquid by the compressor unit (3), - moving the outlet opening (11) closer to the surface of the workpiece (15), until it reaches a working distance (d), wherein the working distance is set such that the liquid jet (14) detaches the coating to be removed from the surface of the workpiece without damaging the workpiece itself, - alternately allowing and interrupting the liquid jet (14) from the outlet opening (11) by the interrupter unit (8), wherein at the same time the nozzle is moved in a working direction (22) in relation to the workpiece.