 메탈 오링(Metallic O-Ring)은 영문 참조
7-1) Metallic O-ring
This O-rings are used when elastomers and other non metallic seals will not seal properly or do not offer the requited reliability for the application, usually as a result of temperatures, pressures, or the environment. This seals are long lasting seals and unlike non-metallic seals, they are not subject to failure due to incompatibility with the environment, out gassing or from deterioration due to age. It is generally fabricated from tubing. Typical tubing material consists of stainless steel or high temperature alloys such as Inconel. These materials are frequently used because they offer resilient properties that enable the seal to "spring Back".
This seals are used as static face type seals and should not be used as a dynamic seal. While the majority of seals are circular, many seals are produced in rectangular racetrack and other various shapes and configurations.
Shin Won high performance seals provides superior performance for most internal, external and axial applications such as:
Pressure : Ultra high vacuum ∼ high pressure 6500 bar
Temperature : - 252℃ ∼ high temperature 1100℃
Because of these capabilities, Shin Won high performance seals are widely used in critical and demanding applications, including :
- Missile & Space systems Nuclear Reactor & Waste containment systems
- Jet engines, Controls, & Instruments Diesel engines
- High temperature Aircraft systems, Chemical, Petrochemical processing systems
Material
Metal O-Ring are produced of metal tube and solid wire material. The material is shaped and welded to rings or other figurations. The O-Ring consists of stainless steel304, 316, 321(-252℃~+260℃), inconel 600(+260℃~+430℃), inconel X-750(+430℃~+980℃) and electroplated with indium(80℃), PTFE(220℃), copper(500℃), silver(800℃), gold(850℃), nickel(980℃).
O-Ring size and Groove dimensions (mm)
thickness outside dia. groove depth groove width groove O.D. groove I.D. Ring tolerance
0.9 6.4 ~ 100 0.60~0.68 1.4 B+0.10/0.20 A-0.10/0.20 ±0.08
1.6 16.0 ~ 250 1.15~1.25 2.3 B+0.10/0.20 A-0.10/0.20 ±0.08
2.4 25.4 ~ 500 1.80~1.95 3.0 B+0.15/0.25 A-0.15/0.25 ±0.13
3.2 50.8 ~ 1000 2.40~2.60 4.0 B+0.20/0.35 A-0.20/0.35 ±0.13
4.0 76.2 ~ 1250 3.05~3.25 5.0 B+0.25/0.40 A-0.25/0.40 ±0.15
4.8 100 ~ 1500 3.70~3.90 6.2 B+0.25/0.40 A-0.25/0.40 ±0.18
6.4 127 ~ 2500 5.00~5.20 8.2 B+0.30/0.50 A-0.30/0.50 ±0.20
* groove O.D. : for internal pressure, B is max. outside dia.(mm)
* groove I. D. : for external pressure, A is min. inside dia.(mm)
Surface finish
- Ra = 0.4 ㎛, N5 : for uncoated O-Ring
- Ra = 0.8 ~ 2.54 ㎛, N6 ~ N8 : for coated O-Ring
- Ra = 0.4 ㎛, N5 : for gases, vacuum, liquids of low viscosity, water
- Ra = 0.8 ㎛, N5 : for medium
7-2) Metal Boss Seal
Application
Advancements in Aerospace performance has resulted in increased engine temperature for longer distances and at higher altitudes. These demand hydraulic systems that are more reliable while operating at higher pressure. Leakage and loss of pressure caused by the degradation of elastomeric or polymer based seals are a problem and the primary reasons for failure in hydraulic systems. The Boss seal is designed to handle high pressures and temperature for long service cycles.
Material
Boss seals are produced from the high temperature alloy X750 (AMS 5598). A soft on the seal is highly recommended to eliminate galling and fretting between the seal and metallic mating components. Silver plating to the AMS 2410 specification with a thickness of .0025mm is recommended. other plating and coating ; Copper, Gold, Soft Nickel, PTFE.
The Boss seal specifications
Materials : Alloy X750(AMS 5598) Silver (AMS 2410)
Temperature range : -55℃ ∼ +650℃
Pressure : Up to 650 bar
Features
Pressure energized for enhanced sealing
Metallic insert captures seal and ensures proper alignment
7-3) Metallic C-Ring
Pressure fluctuations and heat are constant concerns for designers of aircraft engines, valves, pressure transducers exhaust manifolds and fuel injectors. A combination of these two factors can result in premature failure or short seal life. C-ring seals can help overcome both heat and pressure pulsating sealing problems. Key to the seal's performance is the high spring back characteristic due to the C-shaped construction. These highly resilient seals can be used for internal, external and axial pressure under extreme conditions that preclude the use of gaskets made of organic materials. This uniquely fabricated seal configuration is capable of producing relatively high levels of spring back. The compression of the seal in a controlled groove or between two radial interfaces, produces a counter load, generating an effective sealing action that is ideal for these special application.
Basic design characteristics
C-ring seals will undergo plastic deformation when installed at the 20% recommended compression. These C-ring seals may be reusable in their original cavities or in cavities that are nearly the same depth as the original. C-ring seals have much lower initial flange load requirements than O-rings. However, it is still high enough to provide effective smearing of the plating or coating used on the sealing surfaces. Deflection capability is excellent and it is normally assumed to be about half of the spring back, however, this is a function of the operating conditions and the required leakage rate.
Determining factors in seal selection
In the seal selection process, the designer should always keep in mind the following rules.
- There is a direct relationship between seal O.D. and free height
- Larger free height always provides a better performing, more consistent seal.
The seal selection is a process of optmising design limitation, size, available load, spring back, design requirements and cost.
The most important factors in C-ring seal design are :
- Maximum pressure and direction
- Extreme operating temperature.
- Allowable leakage rate.
- Available flange load.
High performance Metallic seal type :
- Internal pressure
- External pressure
- Axial pressure
Deflection capability
We define this as the ability to continue to seal as the flanges separate under pressures.
This function is related to free height, material type, heat treatment and diameter. All things being equal, the larger the free height the more resilient the seal. More resilient seals allow for some tolerance on flanges which are out flat and parallel.
8) Material types, platings and Coatings
It can be made of almost any alloy that can be formed. However, because strength and temperature properties are the primary technical consideration, we produce our seals primarily from Alloy X750 or 718 materials. Other high temperature alloys are also available.
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