Pressure energized

Cross-section and wall thickness designed to control loading

Available for internal, external and axial pressure

Range of materials (Alloy X750, 718, Waspaloy and other exotic metals)

Platings and coatings: silver, gold, PTFE (others available)

Temperature range: from -273°C to 730°C (-460°F to 1350°F)

Pressure range: from medium vacuum to 2,000 bar (29,008 PSI)

Leak range: Approximately ≤ 25 cc/min @ 50 psig Nitrogen per inch of diameter to ≤ 1 x 10-4 std.cc/sec Air. The actual leak rate will depend on seal load, surface finish, and surface treatment.

Optional Features

Tribological wear-resistant coatings available

Custom shapes and sizes available

Oil & gas: downhole drilling/MWD

Industrial turbines: fuel systems/nozzles

Valves: body/bonnet, back seat sealing

Aerospace/space: turbopump, fuel systems, nozzles/injectors, cryogenics

Automotive: turbochargers, exhaust

Abstract:

 With the rapid development of industries such as motorcycles, automobiles, heavy-duty trucks, machinery and equipment, the supply and demand of gas have rapidly increased. For the use of gas in heavy-duty trucks, in order to achieve safety and efficiency and ensure driving comfort and safety. Therefore, this article introduces the application of metal V-rings in heavy-duty truck gas outlets, including the design, manufacturing materials, manufacturing process, and application principles of V-rings at gas outlets. At the same time, the performance of the V-ring was tested and analyzed, proving its excellent performance in heavy-duty truck gas systems, providing the industry with more choices.

Keywords: 

Metal V-shaped ring; Heavy trucks; Gas system, gas outlet; application

一、 Introduction

With the gradual introduction of national environmental protection policies, the logistics industry is gradually moving towards the use of LNG (liquid natural gas) in order to achieve fuel conservation and environmental protection. At the same time, the competition in the logistics industry is becoming increasingly fierce, and the operational stability, comfort, and safety of heavy-duty trucks have put forward higher requirements for products. As a result, the stability of heavy-duty truck gas exports has become a hot topic of concern in the logistics industry. In order to solve this problem, metal V-rings have become an important solution and have been increasingly applied.

二、 Design and Manufacturing of Metal V-Rings

A Metal V-ring is a sealing structural component, with a structural form similar to a V-shaped elastic body. When external force acts on the ring or the "V" bending angle changes, the V-ring will form pressure within a certain range and transmit it to the surrounding sealing area.

In the gas system of heavy-duty trucks, the most important point of V-rings is that they must be stable and reliable. In the application of gas systems, the design and manufacturing of V-rings must strictly comply with standards to ensure their reliable quality.

The design of the V-ring needs to be adjusted according to the requirements of different heavy-duty trucks to ensure good sealing during the assembly process.

When manufacturing metal V-rings, high-quality metal materials should be used. Generally speaking, materials such as galvanized steel plate, stainless steel plate, hard aluminum, brass, titanium alloy, etc. can be used. Among them, 316L stainless steel has good corrosion resistance and is suitable for the chemical, aerospace, food, and pharmaceutical industries. It is also a commonly used manufacturing material for heavy-duty truck gas systems.

三、 Manufacturing process of metal V-rings

The manufacturing process of metal V-rings directly affects their quality. In general, manufacturing processes include multiple stages such as cutting, forming, and forming.

1. Cutting

In the production of metal V-rings, the first step is to choose good manufacturing materials. Then, develop corresponding molds for different requirements and equipment architectures, and use cutting, mold opening, or sleeve disassembly methods for cutting.

2. Forming

After cutting, the metal plate will be strictly formed according to the requirements of the mold. Firstly, quantitative punching is required to empty the center of the board and form the basic shape of a circular ring. Then, bend and press the edges through the mold to form the final "V" opening shape.

3. Forming

The so-called forming refers to further mechanized processing of V-rings, making them into standard shapes and sizes, and then processing and reinforcing them through processes such as processing, heat treatment, and surface treatment.

四、 The Application of Metal V-Rings in Gas Exports

Metal V-rings are mainly used for sealing gas systems, ensuring that gas does not leak out and playing a good role in difficult to seal situations.

Application principle: The inner side of the V-shaped ring is V-shaped, and the outer side is circular, belonging to an elastic structure. When external pressure acts on the V-ring, the V-ring will shrink, and when the pressure disappears, it can return to its original state. Moreover, during the process of combining with the valve, the V-ring ensures the reliability of the seal.

五、 Performance testing and analysis

In order to verify the performance of metal V-rings in heavy-duty truck gas systems, their performance was tested. Experimental tests have shown that metal V-rings have good reliability and stability, and can continuously maintain their sealing performance during multiple compression and decompression processes. In addition, its ability to withstand pressure is relatively strong, and it can still ensure density under high-intensity pressure.

六、 Conclusion and Outlook

The application of Metal V-rings in heavy-duty truck gas systems is an important technology, and its reliability and stability have been verified. In the future, with the development of the industry and technological progress, this technology will further enhance the quality of production, improve the reliability and safety of the entire vehicle

Unlock a New Realm of High - end Sealing in Biomedicine! Shanghai Raido's Spring - Reinforced Metal C - shaped Sealing Rings Reshape the Reliability of Medical Equipment

In the field of biomedicine, every precise operation of high - end medical equipment is crucial to patients' life, health, and treatment effects. Shanghai Raido's painstakingly developed spring - reinforced metal C - shaped sealing rings (gold/silver plated) have emerged as the ideal choice for high - end sealing in biomedicine with their outstanding performance. Tailored for advanced medical CT systems and other high - end medical applications, they meet strict requirements and safeguard the stable operation of equipment.

Our spring - reinforced metal C - shaped sealing rings boast four core advantages. Their high - temperature resistance is remarkable, enabling reliable operation at extreme temperatures of up to 750°C. Whether in the high - temperature environment generated by long - term operation of CT equipment or the high - temperature conditions of proton therapy systems, they can always maintain sealing performance and ensure stable equipment operation. The high - pressure resistance is equally impressive, capable of withstanding a huge pressure of up to 1500 bar, providing solid and reliable sealing for CT equipment under high - pressure conditions, eliminating any concerns about equipment operation. The corrosion resistance is also not to be underestimated. Made of special corrosion - resistant materials and treated with gold/silver plating, they can still be used for a long time in the harsh chemical environments such as acids and alkalis commonly found in medical equipment, significantly reducing equipment maintenance costs and replacement frequency. The ultra - high vacuum sealing performance is a highlight. With an excellent leakage rate as low as 1×10⁻¹⁰ Pa·m³/s, they can maintain extremely high precision and stability in ultra - high vacuum applications, creating a stable and reliable working environment for key components such as accelerators in proton therapy systems, X - ray tubes, and detectors in CT imaging equipment.

This sealing ring has a wide range of applications in the field of biomedicine. For proton therapy systems, it is the key to ensuring the accuracy of accelerators and key components, guaranteeing the precise transmission and focusing of proton beams and helping to improve the effectiveness of cancer treatment. In CT imaging equipment, it effectively enhances the reliability of key components such as X - ray tubes and detectors, reduces external interference, and makes imaging clearer and diagnosis more accurate. In addition, it is also suitable for high - end medical equipment such as MRI systems and radiological imaging tools. Whether it is resisting external magnetic field interference or preventing liquid leakage, it can handle it with ease, fully meeting the sealing requirements of high - end medical equipment.

Shanghai Raido has always been driven by innovation and is committed to providing better sealing solutions for the field of biomedicine. Choosing our spring - reinforced metal C - shaped sealing rings means choosing to safeguard the reliability and stability of medical equipment. Let's join hands to create a bright future in the field of biomedicine!

Stainless steel 316L metal O-rings are critical sealing components in melt filters. Their application is highly compatible with the process characteristics and operating requirements of melt filtration, playing an irreplaceable role in ensuring stable equipment operation, filtration efficiency, and product quality. This article provides a detailed analysis from the aspects of application background, core functions, compatibility analysis, practical application scenarios, and precautions: 

## I. Application Background: Operating Characteristics and Sealing Requirements of Melt Filters  

Melt filters are widely used in industries such as plastics, chemical fibers, rubber, food, and pharmaceuticals. They are primarily used to filter impurities, gel particles, or unmelted substances from molten materials (e.g., polymer melts, resins, food melts) to ensure the quality of subsequent processing (e.g., spinning, film extrusion, injection molding). Their core operating characteristics impose stringent requirements on sealing components: 

1. **High-temperature environment**: Melt temperatures typically range from 150°C to 400°C (e.g., polyester melts at approximately 280–300°C, nylon melts at 240–260°C), with some engineering plastic melts reaching even higher temperatures. 

2. **High-pressure conditions**: Materials must maintain a certain pressure (usually 0.5–3 MPa) during filtration to drive the melt through the filter medium, avoiding pressure fluctuations that could destabilize flow rates. 

3. **Medium properties**: Melts are mostly viscous polymer materials, some containing trace corrosive additives (e.g., antioxidants, flame retardants). Additionally, sealing materials must not contaminate the melt (especially in food and pharmaceutical fields). 

4. **Frequent disassembly needs**: Filters require regular replacement of filter elements. Sealing components must withstand repeated mechanical stress from disassembly and quickly restore reliable sealing after each operation. 

## II. Core Functions of Stainless steel 316L metal O-rings  

In melt filters, Stainless steel 316L metal O-rings are mainly used for static sealing of critical interfaces such as **filter body and end cover, filter cavity and flange, and inlet/outlet joints**. Their core functions include: 

1. **Preventing melt leakage**: Through rigid metal sealing and interference fit, they block high-temperature, high-pressure melt from seeping through sealing gaps, avoiding material waste, equipment contamination, and safety hazards (e.g., burns from contact with high-temperature melt). 

2. **Ensuring stable filtration pressure**: Seal failure can cause pressure loss, affecting melt flow rate through the filter medium and filtration efficiency. The high strength and deformation resistance of stainless steel O-rings maintain stable system pressure. 

3. **Avoiding medium contamination**: Stainless steel (e.g., 316L) has excellent chemical inertness, does not react with melts, and does not release impurities at high temperatures, meeting cleanliness requirements in food, pharmaceutical, and other fields. 

4. **Adapting to frequent maintenance**: Compared to rubber or non-metallic seals, stainless steel O-rings offer better wear resistance and fatigue resistance, retaining sealing performance after multiple disassembly cycles, thus reducing maintenance frequency and costs. 

## III. Compatibility Analysis of Stainless steel 316L metal O-rings  

### 1. Material Compatibility: Meeting High-Temperature and Corrosion Resistance Needs  

- **High-temperature stability**: Commonly used 304 and 316 stainless steels can operate stably below 400°C for long periods. Their melting points (1300–1400°C) are much higher than the operating temperatures of melt filters, preventing softening, aging, or failure due to high temperatures (rubber seals typically age above 200°C and cannot withstand long-term high temperatures). 

- **Corrosion resistance**: 316 stainless steel, containing molybdenum, exhibits stronger resistance to trace acidic/alkaline additives, moisture, or residual solvents in melts. It is particularly suitable for filtering engineering plastic melts with corrosive components (e.g., PVC, fluoropolymers). 

### 2. Structural and Sealing Principle Compatibility: Addressing High Pressure and Surface Defects 

- **Interference sealing of solid structure**: Stainless steel 316L metal O-rings have a solid circular cross-section. During installation, they form an interference fit with the seal groove, undergoing slight elastic deformation under preload to fill micro-scratches and roughness defects on the sealing surface, creating an initial seal. As system pressure increases, melt pressure further compresses the O-ring, enhancing contact stress on the sealing surface (the "self-tightening seal effect"), which adapts to the high-pressure conditions of filters. 

- **Reliability of metal-to-metal sealing**: Compared to the "elastic sealing" of rubber O-rings, the "metal-to-metal" sealing of stainless steel O-rings is more resistant to extrusion—they are less likely to be damaged by extrusion through gaps under high pressure, making them particularly suitable for high-pressure sealing of large-diameter interfaces such as filter end covers. 

### 3. Mechanical Performance Compatibility: Withstanding Disassembly and Long-Term Use 

- **High strength and fatigue resistance**: Stainless steel has high tensile strength (approximately 520 MPa for 304 stainless steel), making it resistant to plastic deformation or fracture under repeated preload from disassembly. Its service life is much longer than that of non-metallic seals, reducing the cost of frequent replacements. 

- **Dimensional stability**: Stainless steel has a low thermal expansion coefficient (approximately 17×10⁻⁶/°C), resulting in minimal dimensional changes under high-temperature conditions. This maintains a stable interference fit, preventing increased sealing gaps and leakage due to thermal expansion and contraction. 

## IV. Practical Application Scenarios and Typical Cases  

1. **Plastic extrusion melt filters**:  

   In PE and PP film extrusion production lines, melt filters remove impurities from raw materials to ensure film transparency. Stainless steel O-rings are used for flange sealing between the filter housing and filter cartridge, withstanding melt temperatures of 200–300°C and pressures of 1–2 MPa to prevent production interruptions and material waste caused by melt leakage. 

2. **Chemical fiber spinning melt filters**:  

   In polyester and nylon spinning processes, melt purity directly affects yarn quality (e.g., breakage, fuzz). 316 stainless steel O-rings provide sealing for high-precision filters, not only withstanding 280°C temperatures but also avoiding melt contamination and spinning defects due to their clean, non-leaching properties. 

3. **Food-grade melt filters**:  

   In filtering food melts such as chocolate and syrup, compliance with FDA and other food contact standards is required. 304 stainless steel O-rings are non-toxic and non-migratory, and they withstand high-temperature disinfection (e.g., steam cleaning), adapting to hygiene requirements in the food industry. 

## V. Application Precautions  

1. **Sealing surface processing precision**: Stainless steel O-rings require high surface roughness of the sealing surface (typically Ra ≤ 1.6 μm). Surface scratches or depressions can cause seal failure, so the processing quality of seal grooves and flange surfaces must be ensured. 

2. **Preload control**: Insufficient preload leads to poor initial sealing, while excessive preload may cause over-deformation of the O-ring or damage to the sealing surface. 

3. **Material selection**: 304 stainless steel is suitable for general conditions, while 316L stainless steel is preferred for corrosive media or high cleanliness requirements. Avoid use in extremely corrosive environments containing sulfur or chlorine (special coatings or alloy materials may be required). 

4. **Installation and maintenance**: Avoid scratching the O-ring with sharp edges during installation. Regularly inspect the sealing surface for wear or corrosion, and replace the O-ring promptly if deformation or cracks are found. 

## VI. Conclusion  

FKM Rubber Gaskets  

FKM (Fluoroelastomer), also known as fluororubber, is a synthetic rubber with a high fluorine content, copolymerized from fluorinated monomers. The large number of C-F bonds in its molecular structure endow the material with excellent chemical resistance, high-temperature resistance, and anti-aging properties. Therefore, FKM rubber gaskets are widely used in industrial scenarios with strict sealing performance requirements. The following is a detailed introduction from aspects of core performance, typical application scenarios, advantages and limitations: 

## I. Core Performance of FKM Rubber Gaskets  

The molecular structure of FKM rubber is dominated by stable carbon-fluorine bonds, featuring strong chemical inertness and excellent physical and mechanical properties, specifically manifested as follows: 

### 1. Chemical Resistance 

- **Broad-spectrum medium resistance**: It has strong resistance to most organic solvents (such as ketones, esters, ethers, aromatic hydrocarbons), strong acids (such as sulfuric acid, nitric acid), strong alkalis, greases, hydraulic oils, fuel oils (including gasoline, diesel, aviation kerosene), and corrosive gases (such as chlorine, fluorine). It is not prone to swelling, hardening, or degradation.  

- **Adaptability to special environments**: It can maintain stable performance in strong oxidizing environments (such as scenarios containing ozone and hydrogen peroxide), making it one of the few rubber materials applicable to the sealing of strongly corrosive media. 

### 2. High-Temperature Resistance  

- **Long-term operating temperature range**: It can work stably for a long time in the range of **-20℃~200℃**. Some high-performance grades (such as perfluoroether rubber) can withstand short-term temperatures up to 260℃ or even 300℃, far exceeding the heat resistance limit of ordinary rubbers (such as EPDM and nitrile rubber). 

- **High-temperature stability**: It is not easy to soften, flow, or decompose in high-temperature environments, and has a low compression set rate (usually <30% under long-term high temperatures), which can continuously ensure the sealing effect. 

### 3. Anti-Aging and Weather Resistance  

- **Anti-aging ability**: It has strong resistance to oxygen, ozone, ultraviolet rays, and climatic aging (such as sunlight, rain, and humidity changes). It is not prone to cracking, hardening, or performance attenuation after long-term use, and its service life is much longer than that of ordinary rubber gaskets. 

- **Radiation resistance**: Some FKM grades have certain radiation resistance and can be used for sealing needs in low-dose radiation environments.  

### 4. Physical and Mechanical Properties 

- **Sealing performance and elasticity**: It has good elasticity and compression rebound, which can closely fit the sealing surface. Even under working conditions with vibration or pressure fluctuations, it can maintain reliable sealing and reduce the risk of leakage. 

- **Wear resistance and strength**: It has moderate surface hardness, better wear resistance than EPDM, and high tensile strength and tear strength, which can adapt to certain mechanical stresses. 

## II. Typical Application Scenarios of FKM Rubber Gaskets 

Based on the above excellent properties, FKM rubber gaskets are mainly used in industrial fields with extremely high requirements for sealing performance, temperature resistance, and corrosion resistance:  

### 1. Petrochemical and Fine Chemical Industry 

- Used for sealing reactors, storage tanks, pipeline flanges, and valves, adapting to various corrosive media (such as acid-base solutions, organic solvents, catalysts) and high-temperature working conditions (such as distillation and polymerization processes). 

- Adapt to the sealing of oil extraction equipment (such as drilling platform seals), refinery pipelines, and heat exchangers, resisting corrosion from crude oil, heavy oil, and various refined by-products. 

### 2. Automobile and Transportation 

- Automotive engine systems: Used for sealing high-temperature components such as fuel injection systems, gearboxes, and turbochargers, withstanding long-term erosion from engine oil, high-temperature coolants, and fuel.  

- New energy vehicles: Adapt to battery cooling systems and motor seals, resisting coolants (such as ethylene glycol solutions) and high-temperature environments, while meeting voltage resistance and insulation requirements. 

- Aerospace: Used for sealing aircraft engine fuel systems, hydraulic systems, and high-temperature pipelines, adapting to harsh environments such as high-altitude low temperatures, ground high temperatures, and aviation fuel. 

### 3. Machinery Manufacturing and Industrial Equipment 

- High-temperature machinery: Such as sealing gaskets for industrial furnaces, dryers, and steam pipelines, withstanding continuous high temperatures and thermal cycle impacts. 

- Hydraulic and pneumatic systems: Used for sealing high-pressure hydraulic equipment and pneumatic valves, resisting the long-term effects of hydraulic oil and compressed air, and not prone to aging and failure at high temperatures. 

### 4. Electronics and Semiconductor Industry  

- Semiconductor manufacturing equipment: Such as sealing components of etching machines and ion implanters, withstanding corrosive gases such as hydrogen fluoride (HF) and chlorine, and high-temperature process environments. 

- Electronic component sealing: Used for waterproof and dustproof sealing of high-temperature electronic equipment (such as power modules), adapting to the high-temperature environment during equipment operation. 

### 5. Food and Pharmaceutical Industry (Specific Grades) 

- Food-grade FKM gaskets that meet FDA (U.S. Food and Drug Administration) or USP (U.S. Pharmacopeia) standards can be used for sealing high-temperature sterilization equipment (such as steam sterilizers) and food processing machinery. They withstand corrosion from high-temperature steam and cleaning agents, are non-toxic, and do not release harmful substances. 

## III. Advantages and Limitations of FKM Rubber Gaskets  

### Advantages  

- **Extremely strong chemical resistance**: Adapt to most acids, alkalis, solvents, and corrosive media, with a much wider application range than ordinary rubber; 

- **Outstanding high-temperature resistance**: Can be used for a long time above 200℃, meeting the needs of high-temperature industrial scenarios; 

- **Anti-aging and long service life**: Excellent ozone and ultraviolet resistance, not easy to fail in outdoor or long-term use, reducing maintenance costs; 

- **High sealing reliability**: Good elasticity and compression rebound, can maintain effective sealing under vibration and pressure fluctuation conditions. 

### Limitations 

- **Limited low-temperature performance**: Ordinary FKM tends to harden and lose elasticity below -20℃, and low-temperature sealing performance decreases (special low-temperature grades need to be selected, which are more costly); 

- **High cost**: The price of raw materials is much higher than that of general-purpose rubbers such as EPDM and nitrile rubber, making it unsuitable for sealing needs in low-cost and non-harsh working conditions; 

- **Limitations on polar solvents**: Although it is resistant to most media, it may have a risk of swelling in a few strong polar solvents (such as low-molecular ketones), so compatibility testing in advance is required; 

- **Difficult processing**: The vulcanization molding process has high requirements, and temperature and time need to be precisely controlled, otherwise, performance may be affected. 

## IV. Selection Considerations 

- **Confirmation of medium compatibility**: According to the specific media in the use environment (such as acid, alkali, solvent type), verify compatibility through the chemical resistance data sheet provided by the manufacturer or actual tests; 

- **Temperature range matching**: Clarify the long-term use temperature and short-term peak temperature of the working condition, and select the FKM grade corresponding to the temperature resistance level (such as ordinary FKM or perfluoroether rubber);  

- **Consideration of low-temperature needs**: If the working condition involves a low-temperature environment (such as below -20℃), modified low-temperature FKM or perfluoroether rubber should be selected to avoid hardening and failure of the gasket; 

- **Balance between cost and performance**: In non-high-temperature and non-strongly corrosive scenarios, rubbers with higher cost performance (such as EPDM and nitrile rubber) can be preferred. FKM is more suitable for harsh working conditions. 

## Summary 

With the three core advantages of "chemical resistance, high-temperature resistance, and anti-aging", FKM rubber gaskets have become a "high-end solution" in the industrial sealing field to cope with harsh environments. They are particularly indispensable in high-demand scenarios such as petrochemicals, automobiles, and semiconductors. Although the cost is relatively high, their ultra-long service life and reliable sealing performance can significantly reduce the risk of equipment maintenance, making them an ideal choice for sealing high-value equipment.

Raido Spring-Energized Hollow Metal ORings: Innovative Sealing Solution​

The newly launched spring-reinforced metal hollow Oring (also referred to as spring energized metal oring seals) by Raido is an innovative upgraded product developed based on the basic hollow metal oring seal. As a high-performance sealing component with unique structural design and outstanding functionality, it combines the advantages of traditional spring-energized hollow metal orings while achieving significant upgrades in sealing performance and working condition adaptability. Below is a comprehensive detailed introduction:​

1. Structural Features​

1.1 Core Structural Design​

The traditional spring-energized hollow metal oring is typically formed by bending a thin-walled seamless tube into a circular shape, with its two ends butt-welded to create a hollow interior. Raido’s upgraded product inherits this hollow structure while elevating it with a key innovation: high-performance elastomers (springs) are precisely installed in the inner cavity. Through the elastic support of the springs, the product forms a unique composite sealing structure of "metal skeleton + elastic compensation" — the metal hollow body serves as a rigid skeleton to ensure structural stability and resistance to extreme conditions, while the embedded springs provide continuous elastic force, addressing the limitations of traditional sealing components.​

1.2 Material Matching​

To maximize performance, Raido scientifically matches materials for the metal body and springs:​

• Metal body: Options include stainless steel, high-temperature alloys, and other materials, selected based on specific application requirements (e.g., corrosion resistance, high-temperature tolerance);​

• Springs: Made of special elastic alloys, ensuring excellent elasticity, fatigue resistance, and compatibility with the metal body to avoid issues like galvanic corrosion.​

2. Performance Advantages​

Building on the inherent strengths of traditional spring-energized hollow metal orings, Raido’s product achieves further breakthroughs in sealing efficiency and durability:​

2.1 High Elasticity and Superior Recovery Capacity​

Like traditional models, the embedded springs enable the oring to quickly rebound after significant compressive deformation, effectively compensating for wear, thermal deformation, or assembly errors that could degrade sealing performance. This ensures long-term stability even in dynamic working environments.​

2.2 Enhanced Sealing Reliability (Key Innovation)​

A standout advantage of Raido’s design is its ability to address sealing surface defects. When the sealing surface has minor scratches, unevenness, or other flaws, the springs generate continuous and uniform compensating force through their own elasticity. This force pushes the metal body to closely fit the sealing surface, effectively offsetting various defects on the surface, greatly reducing leakage risks, and delivering far better sealing performance than traditional hollow metal orings (which often fail to seal properly on imperfect surfaces).​

2.3 Strong High-Pressure Resistance​

The "metal skeleton + spring" structure significantly improves pressure collapse resistance. While traditional spring-energized hollow metal orings can handle pressures up to 40MPa (with some ultra-high-pressure models reaching over 100MPa), Raido’s product, through precise regulation of spring strength, can withstand extreme pressure conditions ranging from ultra-high vacuum to a maximum of over 200MPa. It maintains reliable sealing whether under internal or external pressure, making it suitable for ultra-high-pressure scenarios.​

2.4 Low Compression Set​

During long-term use, the product exhibits minimal compression set — the metal body retains its shape stability, and the springs do not lose elasticity due to fatigue. This ensures consistent sealing performance over time, reducing equipment maintenance and replacement costs caused by seal failure.​

2.5 Excellent Adaptability to Harsh Environments​

The metal body itself provides inherent resistance to high/low temperatures and corrosion, and when combined with the reinforcing effect of the springs, Raido’s oring excels in extreme environments:​

• It easily copes with temperature ranges from an ultra-low -196℃ (matching the low-temperature tolerance of traditional models for cryogenic media like liquid oxygen/liquid nitrogen) to an ultra-high temperature above 1000℃ (surpassing the high-temperature limit of some traditional models). It maintains stable sealing performance even during high-low temperature alternating cycles;​

• The corrosion-resistant metal body (e.g., stainless steel, high-temperature alloys) and compatible springs ensure resistance to strong corrosive media such as acids, alkalis, seawater, and radioactive substances, avoiding seal failure due to corrosion.​

3. Application Scenarios​

Leveraging its "extreme condition adaptability" — a core advantage of spring-energized hollow metal orings — Raido’s product is widely applicable in high-end fields with stringent sealing requirements, replacing ordinary rubber orings (poor resistance to high/low temperatures and corrosion) and simple metal orings (poor low-pressure sealing and no wear compensation). Key application areas include:​

3.1 Extreme Temperature Conditions​

• Low-temperature fields: Sealing for liquid oxygen/liquid nitrogen storage tanks, valves in LNG (liquefied natural gas) transmission pipelines, and low-temperature propellant systems in aerospace (temperatures as low as -196℃ to -270℃);​

• High-temperature fields: Sealing for boiler flue dampers, gas turbine shaft ends, automotive exhaust treatment systems, observation windows of industrial kilns, and high-temperature components in aerospace (temperatures up to 600℃ to over 1000℃).​

3.2 High/Low Pressure and Vacuum Conditions​

• High-pressure fields: Sealing for high-pressure cylinder pistons in hydraulic systems, high-pressure wellheads of oil drilling platforms, pump bodies of high-pressure water jets, and ultra-high-pressure valves in high-end equipment (pressures ranging from 20MPa to over 200MPa);​

• Vacuum fields: Sealing for semiconductor vacuum coating machines, vacuum drying oven doors, and aerospace vacuum chambers (vacuum degree up to 10⁻³Pa to 10⁻⁵Pa).​

3.3 Strong Corrosion Conditions​

• Chemical industry: Sealing for inlet/outlet valves of hydrochloric acid/sulfuric acid storage tanks, electroplating tanks, and pesticide production equipment;​

• Marine engineering: Sealing for seawater desalination equipment and hydraulic systems of offshore platforms (resistant to seawater corrosion);​

• Nuclear industry: Sealing for cooling systems of nuclear reactors (resistant to corrosion from radioactive media and high-temperature water);​

Metal Corrugated Reinforced PTFE envelope Gasket (TEFLON + STAINLESS STEEL) Product Description

The metal corrugated  reinforced PTFE envelope Gasket is a composite sealing component that combines the excellent chemical stability of polytetrafluoroethylene (TEFLON) and the high-strength support of stainless steel. With its unique "corrugated  structure + double-layer material" design, it becomes an ideal sealing solution for harsh working conditions in chemical, petroleum, pharmaceutical and other industries.

I. Core Materials: Scientific Integration of Dual Advantages

1、Surface Layer: Polytetrafluoroethylene (TEFLON)

As the direct contact layer of the sealing surface, PTFE material has the characteristic of "the king of corrosion resistance" — it can withstand an extreme temperature range from -200℃ to 260℃, and has no chemical reaction with strong acids (such as hydrochloric acid, sulfuric acid), strong alkalis (such as sodium hydroxide), strong oxidants and various organic solvents, completely solving the leakage problem of traditional gaskets caused by corrosion. At the same time, its ultra-low friction coefficient (only 0.04) can reduce the wear of the sealing surface, and its non-stick surface can avoid medium residue, meeting the cleanliness requirements of the food and pharmaceutical industries.

2、Base Material: Stainless Steel

The corrugated tooth base made of 304 or 316L stainless steel provides strong structural support for the product. The high-strength property of stainless steel (tensile strength ≥ 520MPa) can resist compressive deformation under high-pressure working conditions, while the corrugated tooth design compensates for minor unevenness of the flange surface through the "elastic buffer layer" effect. Even in scenarios with vibration or temperature fluctuation, it can still maintain stable sealing specific pressure, avoiding sealing failure caused by excessive rigidity of the base material.

II. Structural Design: Sealing Innovation of Corrugated Tooth Technology

The product adopts a composite structure of "stainless steel corrugated tooth base + PTFE coating". The peak-valley spacing of the corrugated  is precisely calculated (conventional tooth height: 0.2-0.5mm, tooth pitch: 1-3mm), forming multiple sealing cavities:

• When the flange bolts are tightened, the PTFE surface layer will produce "stepwise deformation" with the compression of the corrugated tooth structure. While filling the flange gap, the peak of the corrugated  forms line contact sealing with the flange surface, greatly improving the sealing specific pressure;

• The corrugated tooth structure of the stainless steel base can effectively disperse pressure, avoiding cold flow phenomenon of PTFE caused by excessive local stress, and prolonging the sealing life;

• The overall structure has both flexibility and rigidity, which can adapt to slight misalignment of the flange during installation, reducing installation difficulty.

III. Performance Characteristics: Core Advantages for Harsh Working Conditions

1.    Wide Temperature Range Sealing: Maintains stable sealing performance in the range of -200℃ (cryogenic working condition) to 260℃ (high-temperature working condition), suitable for scenarios such as refrigeration equipment and high-temperature reaction kettles;

2.       High-Pressure Resistance: Relying on the support of the stainless steel base, it can withstand a maximum working pressure of 30MPa, meeting the sealing needs of oil pipelines and high-pressure valves;

3.       Chemical Inertness: The PTFE surface layer has no corrosion or swelling to almost all chemical media (except molten alkali metals and chlorine trifluoride), suitable for chemical acid-base transportation pipelines;

4.       Long-Term Stability: The corrugated tooth structure reduces the cold flow and creep of PTFE, and the attenuation rate of sealing performance is less than 5% during long-term use (conventional service life: 3-5 years);

5.       Environmental Compliance: The material meets the standards of FDA (U.S. Food and Drug Administration) and RoHS (EU Restriction of Hazardous Substances), and can be used in fields such as food processing and drinking water treatment.

IV. Application Scenarios and Installation & Maintenance

(I) Typical Application Scenarios

• Chemical Industry: Flanges of acid-base storage tanks, feed inlets of reaction kettles, sealing end covers of chemical pumps;

• Petroleum Industry: Valves of oil transmission pipelines, manholes of crude oil storage tanks, sealing surfaces of oil-gas separators;

• Pharmaceutical Industry: Pharmaceutical liquid transmission pipelines, aseptic reaction tanks, sealing doors of freeze dryers;

• Energy Industry: Cooling systems of nuclear power plants, high-temperature steam pipelines of thermal power plants, production equipment for photovoltaic silicon materials.

(II) Installation and Maintenance Points

1. Before installation, clean the flange surface, remove oil stains, impurities and residues of old gaskets to avoid affecting the sealing effect;

        2.  When tightening the bolts, adopt the "diagonal step-by-step tightening" method to ensure uniform force on                    the gasket, avoiding damage to the PTFE surface layer due to local over-tightening;

        3.   If slight leakage occurs after long-term use, properly retighten the bolts (retightening torque shall not exceed                10% of the initial torque) without replacing the new gasket;

        4.  When the medium temperature exceeds 200℃, it is recommended to check the sealing status every 6 months to ensure no deformation of the corrugated tooth structure.

Through "material complementarity + structural innovation", the metal corrugated  reinforced PTFE envelope Gasket perfectly solves the pain point of traditional gaskets being "corrosion-resistant but not pressure-resistant, or pressure-resistant but not corrosion-resistant". It has become a high-end product with both reliability and adaptability in the modern industrial sealing field, providing safe and long-term sealing guarantees for various harsh working conditions.

PTFE (Polytetrafluoroethylene) envelope gaskets, also known as "PTFE encapsulated gaskets," are widely used in industrial sealing applications due to PTFE’s excellent chemical resistance, non-stick properties, and high-temperature stability. Their core design involves a PTFE outer "envelope" that encapsulates a softer, more compressible inner core (e.g., rubber, graphite, or fiber), combining PTFE’s corrosion resistance with the core’s sealing flexibility. 

Below is a detailed classification of PTFE envelope gaskets based on core material, PTFE envelope structure, and application-specific designs, along with their key characteristics and use cases.

 1. Classification by Inner Core Material  

The inner core is critical for achieving effective sealing (since pure PTFE is relatively rigid and prone to creep). Different core materials tailor the gasket’s compressibility, temperature resistance, and cost. 

 2. Classification by PTFE Envelope Structure  

The design of the PTFE outer layer affects the gasket’s sealing performance, installation ease, and resistance to "cold flow" (PTFE’s tendency to deform under pressure over time). 

 2.1 Full Envelope (Standard Type)  

Design: The PTFE sheet fully wraps the inner core, with the edges of the PTFE sealed (e.g., by heat welding or mechanical crimping) to prevent the core from leaking or being exposed to the medium. 

Advantages: Maximum protection of the core from corrosive fluids; suitable for full-face flange sealing. 

Limitation: Slightly lower compressibility than partial envelope types (due to full PTFE coverage). 

Use Case: Most industrial applications (chemical tanks, pipelines, pumps) where the medium is aggressive.

 2.2 Partial Envelope (Exposed Core Type)  

Design: The PTFE envelope covers only the sealing face (the area in contact with the flange) and the outer perimeter of the core; the inner bore (hole) of the gasket leaves the core partially exposed. 

Advantages: Higher compressibility (since less PTFE restricts the core’s deformation); easier to install in tight spaces. 

Limitation: The exposed core may be vulnerable to corrosion if the medium is highly aggressive. 

Use Case: Low-to-moderate corrosion environments (e.g., water treatment, HVAC systems) where compressibility is prioritized.

 2.3 Reinforced Envelope (Anti-Creep Type)  

Design: The PTFE envelope is reinforced with a thin layer of inert material (e.g., glass fiber, carbon fiber, or metal mesh) embedded in the PTFE matrix. 

Advantages: Significantly reduces PTFE cold flow and creep; maintains sealing integrity under long-term pressure or temperature cycles. 

Limitation: Higher cost than standard PTFE envelopes. 

Use Case: High-pressure/high-temperature applications (e.g., steam turbines, chemical reactors) where creep resistance is critical.

 3. Classification by Flange Type & Shape  

PTFE envelope gaskets are customized to match common flange designs, ensuring proper fit and sealing. 

 4. Specialized PTFE Envelope Gaskets  

These are engineered for niche industries with strict requirements (e.g., food safety, ultra-purity, or extreme environments). 

 4.1 FDA-Compliant Gaskets 

Design: Uses food-grade PTFE (e.g., PTFE meets FDA 21 CFR Part 177.1550) and inner cores (EPDM, Silicone) certified for food contact. 

Use Case: Food & beverage processing (dairy, brewing), pharmaceutical manufacturing (drug synthesis), and cosmetics production.

 4.2 High-Purity (Ultra-Clean) Gaskets  

Design: Made with virgin PTFE (no additives) and a core of high-purity graphite or PTFE foam. The envelope is polished to minimize particle shedding. 

Use Case: Semiconductor manufacturing (ultra-pure water systems), laboratory equipment, and biotech (cell culture reactors).

 4.3 Low-Temperature Gaskets  

Design: Inner core of low-temperature-resistant materials (e.g., silicone rubber, expanded PTFE) to maintain flexibility at -200°C to -50°C. 

Use Case: Cryogenic applications (LNG storage, liquid nitrogen pipelines).

 Summary of Key Selection Factors  

To choose the right PTFE envelope gasket, consider: 

1. Medium Properties: Corrosiveness (dictates PTFE grade and core material). 

2. Operating Conditions: Temperature (graphite core for high temp; silicone for low temp) and pressure (reinforced envelope for high pressure). 

3. Flange Type: Full-face vs. ring-type, standard vs. custom shape. 

4. Industry Standards: FDA, ASME, or ISO compliance (for regulated sectors like food/pharma). 

By aligning these factors with the classifications above, you can ensure optimal sealing performance and long service life.

Detailed Introduction to CIPP Type Double-Stage Single-Liner Metal Seal

1. Core Design and Performance Advantages of the Product

The CIPP Type Double-Stage Single-Liner Metal Seal has become a preferred sealing solution for extreme environments, thanks to its double-stage multi-layer metal composite structure. This structure fundamentally ensures the reliability and effectiveness of the seal under harsh conditions such as high temperature, ultra-high vacuum, and high-energy particle beam radiation, providing stable sealing support for high-demand industrial scenarios.

Its innovative proprietary knife-edge design is a major highlight. It not only accurately compensates for deviations in flange flatness, significantly improving installation convenience and ensuring a secure fit between the seal and the flange but also enhances sealing performance while simplifying the installation process. This makes the overall sealing operation more efficient and reliable, effectively reducing construction difficulty and time costs.

2. Groundbreaking Performance Compared with Traditional Seals

In terms of requirements for flange surface roughness, traditional seals usually require the flange surface roughness (Ra) to be controlled between 0.2-0.4, which imposes extremely high demands on flange machining accuracy. However, the CIPP Type Double-Stage Single-Liner Metal Seal launched by Sonkit breaks this limitation. Even if the flange surface Ra value is as high as 0.8-1.6, it can still achieve effective sealing. This greatly reduces the strict requirements for flange machining and lowers the early-stage machining costs of equipment.

At the same time, the knife-edge design of this seal also significantly reduces the demand for bolt preload. This advantage not only reduces the load on the bolts, extending their service life but also lowers the risk of seal failure caused by improper preload control during installation, further improving the stability of the sealing system.

In terms of leakage rate control, professional test verification shows that the leakage rate of the system using Sonkit's CIPP Type Double-Stage Single-Liner Metal Seal can be reduced to 1E-11 mbarl/s. This value far exceeds the original design requirement of 1E-10 mbarl/s, representing a qualitative leap in sealing performance and providing strong technical support for scenarios with high sealing requirements.

3. Typical Application Scenarios

With its outstanding performance, the CIPP Type Double-Stage Single-Liner Metal Seal is widely used in high-end fields with extremely strict sealing requirements, including:

1.       Fusion Reactors: As a key sealing component for fusion reactions, it needs to maintain sealing integrity under extreme working conditions to ensure the safe and stable operation of the reactor. The double-stage multi-layer structure and low leakage rate characteristics of this seal perfectly meet its requirements.

2.       Tokamak Devices: Tokamak devices have complex structures and require highly specialized and precise sealing solutions. This seal can adapt to their complex design while meeting special needs such as plasma confinement and neutron radiation resistance.

3.       Ultra-High Vacuum Applications: In ultra-high vacuum environments, seals need to maintain excellent sealing performance for a long time. The ultra-high vacuum adaptability of this product makes it an ideal choice for such applications.

4.       Laser and Radio Frequency Guidance Systems: These systems have strict requirements for the reliability and stability of seals. This seal can ensure that the system is not disturbed by the external environment during operation, safeguarding guidance accuracy and system performance.

4. Adaptation to Core Performance Requirements in Application Scenarios

1.       Adaptation to Extreme Operating Temperatures: The seal assembly can always maintain structural and sealing integrity within a wide temperature range of -50°C to 350°C. Whether it is material stability in low-temperature environments or deformation resistance in high-temperature environments, it can meet the usage requirements of extreme temperature scenarios.

2.       Guarantee for Plasma Confinement: In scenarios involving plasma confinement such as Tokamak devices, the seal can operate reliably in strong magnetic fields, effectively blocking external interference, ensuring plasma confinement effects, and providing a stable sealing environment for relevant experiments and production processes.

3.       Neutron Radiation Resistance: For scenarios such as fusion reactors that need to withstand neutron radiation, the sealing system can be exposed to neutron radiation environments for a long time without a decline in sealing performance or leakage caused by radiation, ensuring the long-term safe operation of equipment.

4.       Adaptation to Ultra-High Vacuum Environments: In ultra-high vacuum application scenarios, the seal has excellent vacuum retention capability and can maintain stable sealing performance in ultra-high vacuum conditions for a long time, avoiding the impact of seal failure on the vacuum environment.

5.       Adaptability to Complex Structures: Facing equipment with complex structures such as Tokamak devices, this seal, relying on its highly specialized design and precise manufacturing process, can perfectly adapt to the complex structure of the equipment, ensuring reliable sealing in complex installation environments.

A Tri-Clamp Gasket, also known as a tri-lobe gasket or sanitary gasket, is a type of sealing gasket specifically designed for sanitary connections. Below is a detailed introduction to it:

- **Structural Design**: A Tri-Clamp Gasket is typically used in conjunction with clamp fittings. Its assembly consists of two clamps, one gasket, and two pipe fittings. The gasket is placed between the connecting surfaces of the two pipe fittings, and the clamping force of the clamps compresses the gasket, thereby forming a tight, leak-free sealed connection.

- **Material Types**:

    - **EPDM (Ethylene Propylene Diene Monomer)**: It has an operating temperature range of -20°F to 300°F (approximately -29°C to 149°C). It offers excellent high-temperature resistance and good tolerance to animal and vegetable oils, ozone, steam, water, and oxygenated solvents. It is suitable for applications involving CIP (Clean-in-Place) disinfectants like Oxonia and ozonated water.

    - **FKM/Viton (Fluorocarbon Rubber)**: Its operating temperature range is -30°F to 400°F (approximately -34°C to 204°C). It has higher chemical resistance than most elastomers and excellent compatibility with strong acids. However, it is not recommended for continuous use in SIP (Sterilize-in-Place) procedures.

    - **PTFE/Teflon (Polytetrafluoroethylene)**: With an operating temperature range of -100°F to 500°F (approximately -73°C to 260°C), it boasts extremely strong chemical resistance. Nevertheless, it is not advisable for use in scenarios with frequent large temperature fluctuations, as it lacks memory and may experience a "cold flow" phenomenon.

    - **Silicone Rubber**: Its operating temperature range is -40°F to 450°F (approximately -40°C to 232°C). It exhibits chemical resistance to various common chemicals, including acids, alkalis, and steam, but has only average tolerance to oils.

- **Application Fields**: Tri-Clamp Gaskets are widely used in industries with extremely high sanitary requirements, such as the food, dairy, beverage, biotechnology, and pharmaceutical industries. They are used to seal clamp connections in sanitary piping systems, ensuring that the connections between pipes, valves, pumps, and other process equipment are sanitary, preventing product contamination, and guaranteeing product quality and safety.

- **Performance Advantages**:

    - **Good Sanitary Performance**: It has a smooth, non-porous surface without layered grooves or protrusions, which makes it difficult for bacteria to grow and dirt to accumulate. It complies with relevant sanitary standards and certifications such as FDA and USP Class VI.

    - **Reliable Sealing Performance**: Under the clamping force of the clamps, it can form an excellent sealing effect, effectively preventing the leakage of liquids or gases and ensuring the normal operation of the system.

    - **Easy Installation**: No special tools are required; installation and disassembly can be quickly completed using clamps, facilitating the maintenance and cleaning of equipment.