Vacuum Valve Low Roughness Surface Reduces Particle Formation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vacuum valves face challenges in minimizing the introduction, creation, and transport of undesired particles due to surface roughness, which affects sealing and process conditions in vacuum applications.
Innovation Solution
The valve surfaces are configured with an average roughness depth of less than or equal to 0.4 μm, preferably achieved through milling and turning to a shiny finish, reducing particle adhesion and formation, and are made of materials like aluminum or stainless steel, with optically reflective surfaces to minimize thermal radiation absorption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If conventional valve surfaces are used with standard roughness, then manufacturing is easier and less costly, but particle formation and adhesion increase significantly
Solution Approach 1:
The patent applies parameter changes by specifying a maximum average roughness depth Rz ≤ 0.4 μm for valve surfaces, transforming the surface quality parameter from conventional standards to a controlled low-roughness state. This parameter change directly reduces particle formation and adhesion while maintaining manufacturing feasibility through defined finishing processes.
Solution Approach 2:
The patent implements preliminary action by performing surface finishing operations (milling and turning to shiny finish) during the manufacturing phase to achieve the required Rz ≤ 0.4 μm roughness before the valve enters service. This preliminary surface preparation prevents particle generation during operation without requiring additional maintenance interventions.
2Object-generated harmful factors
If valve surfaces are made very smooth with Rz ≤ 0.4 μm, then particle adhesion is reduced, but cleaning and maintenance become more difficult
Solution Approach 1:
The patent applies parameter changes by establishing a specific roughness threshold (Rz ≤ 0.4 μm) that creates surfaces smooth enough to minimize particle adhesion through reduced surface irregularities, while remaining within capabilities of conventional finishing processes that do not create overly delicate surfaces.
Solution Approach 2:
The patent implies ease of maintenance by suggesting that if particle contamination does occur on the smooth surfaces, the valve components can be relatively easily re-finished or replaced, treating the surface as a consumable element that can be restored through standard machining operations rather than requiring complex cleaning procedures.
3Object-generated harmful factors
If aluminum or aluminum alloys are used for valve surfaces, then cost is reduced and particle formation is minimized, but thermal radiation absorption increases compared to stainless steel
Solution Approach 1:
The patent applies parameter changes by modifying the surface roughness parameter (Rz ≤ 0.4 μm) of aluminum surfaces to such a degree that the smooth finish reduces particle formation mechanisms, while the inherent reflective properties of the smooth aluminum surface partially compensate for thermal radiation absorption concerns.
Solution Approach 2:
The patent applies local quality by specifying that only the particle-contact surfaces (valve seat and closure member sealing surfaces) require the ultra-smooth Rz ≤ 0.4 μm finish, while other non-critical surfaces of the valve body may have different finishes or material properties, allowing optimization of both particle reduction and thermal management in different locations.
4Object-generated harmful factors
If conventional machining finishes are used, then manufacturing is simpler, but micro-burrs form at profile tips causing particle generation
Solution Approach 1:
The patent applies parameter changes by specifying a maximum roughness depth Rz ≤ 0.4 μm that eliminates the formation of micro-burrs at profile tips, transforming the surface topography from a state that generates particles to one that is inherently particle-free, while maintaining compatibility with conventional machining capabilities.
Solution Approach 2:
The patent implements preliminary action by incorporating the high-precision surface finishing (milling and turning to shiny finish) into the initial manufacturing process, removing potential micro-burrs and surface irregularities before the valve components are assembled and put into service, thereby preventing particle generation throughout the operational lifecycle.
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 configuration significantly reduces particle formation and adhesion, allows for easier cleaning, and enhances thermal reflection, leading to more efficient fluid pumping and reduced thermal loads, enabling the use of cost-effective materials in vacuum applications.
Implementation Method 1
both the adhesion and production of disruptive particles can be reduced considerably
Implementation Method 2
optically reflective surfaces to minimize thermal radiation absorption
Implementation Method 3
enhances thermal reflection
Data Source
AI summary
A valve (1), in particular a vacuum valve, having at least one valve housing (2), at least one closure element (3), and at least one valve seat (4). The valve seat (4) surrounds at least one valve opening (5) of the valve (1), and the closure element (3) can be moved back and forth between at least one open position, in which the closure element (3) at least partly releases the valve opening (5), and a closed position, in which a sealing surface (8) of the closure element (3) is pressed against the valve seat (4) in order to close the valve opening (5), by at least one closure element drive (6, 7). At least one surface (9) of the valve (1) has an average surface roughness RZ less than or equal to 0.4 um, preferably less than or equal to 0.25 um.