High sealing
With the Helium leakage testing and ensure that Helium leak rate better than 10-8 Pa · m3/s
High precision
With domestic and foreign high-precision CNC machining equipment ensure the high quality of vacuum products.
Corrosion resistance
Made of materials such as stainless steel 304/316L and other material to improve Corrosion resistance.
Diversification
Common Size range is KF10-KF50 and KF63-KF200.Special Materials,sizes and connection methods can be available upon the request.
Reliable sealing and precise control
KF Centering Rings

KF Centering Rings  are the core positioning and sealing components for ISO-KF standard quick-release vacuum flanges, and an indispensable basic part for fast and reliable connection of small and medium-sized vacuum piping systems.

KF Vacuum Flanges

KF Flange and Fittings is refers to the KF series of vacuum components, a series of standardized connecting parts for vacuum systems,includes KF Centering Rings, KF Vacuum Flanges,KF Vacuum Fittings,KF Vacuum Bellows, KF Nipples and KF Clamps.

The typical KF or NW assembly consists of two identical flanges, a center-ring, and an aluminum clamp with a wingnut fastener frequently connect and disconnect without tools.

KF Vacuum Fittings

KF Vacuum Fittings is a series of connecting parts used in vacuum systems, usually including elbows, tees, crosses, etc., using the clamp connection.A wide range of flange sizes from KF10 to KF50 to meet the needs of vacuum pipe connections of different diameters.

KF Vacuum Bellows

KF Vacuum Bellows is a high-quality flexible connecting pipe for modern industrial piping. We can provide bendable and compressible bellows in sizes from KF10 to KF50 in customized lengths of 100mm, 200mm, 300mm, 500mm, 1000mm and so on.

KF Nipples

KF Nipples are basic and essential connecting components for ISO-KF quick-release vacuum systems, used to connect vacuum chambers, tubes, valves, pumps and other vacuum equipment to form a complete straight vacuum pipeline.

KF Clamps

KF Clamp is usually made of stainless steel 304, 316L or aluminum. It is used to tightly connect two butted KF flanges by wrapping around the flanges and utilizing the clamp's fastening device (e.g., butterfly nut, etc.) to create a tightening force.

Why choose ruijia's
KF Flanges and Fittings
High quality raw materials
Using high-quality materials such as stainless steel andaluminum,it has excellent corrosion resistance, hightemperature resistance, and pressure resistance
Advanced technology and equipment
Vacuum welding and heat treatment, high-precision CNC andfive axis machining, helium mass spectrometry leak detectionensuring high precision and high performance.
Comprehensive testing and quality control
Equipped with complete testing equipment such as heliummass spectrometer and spectrometer, ensuring that eachproduct meets the highest quality standards.
Frequently asked questions
We also have a dedicated FAQ page where we try to answer other questions. Visit the FAQ page.
Learn More
What are the commonly used sizes of KF flange and fittings?

KF Flanges size：KF10，KF16，KF25，KF40，KF50，KF63，KF80，KF100，KF160，etc KF Fittings size：KF10，KF16，KF25，KF40，KF50.e.

What is the connecting pipe size of KF flanges and fittings?

Please refer to the dimensions of the welded pipe:

For USA standard：KF10-12.7MM,KF16-19.05MM, KF25-25.4MM,KF40-38.1MM,KF50-50.8MM

For EUROPE:     KF10-14MM, KF16-20MM,KF25-28MM,KF40-45MM,KF50-57MM.

For JIS standard：KF10-12.7MM,KF16-17.2MM,KF25-34MM,KF40-48.6MM,KF50-52.2MM.

How to reduce the leakage rate of the KF system through

1.Cleaning the sealing surface: Wipe with absolute ethanol after each disassembly and assembly to avoid oil stains and scratches; operate with gloves.

2.Maintaining the sealing ring: Check regularly for aging or damage and replace promptly; store separately in a dry place when not in use for a long time.

3.Proper fastening: Tighten the clamp evenly diagonally to avoid deformation caused by over-tightening.

What materials are KF flanges and fittings available in, and what working environments are they respectively suitable for?

1.304 stainless steel: Resistant to general corrosion (atmosphere, weak acids and alkalis), suitable for conventional vacuum, dry and clean environments (laboratories, food industry).

2.316 stainless steel: Higher corrosion resistance (resistant to seawater, chlorides, moderate acids and alkalis), suitable for chemical industry, coastal areas and other high-humidity/medium-corrosion environments.

How to quickly disassemble KF vacuum flanges and fittings?

1. Pressure relief: Equalize the pressure inside and outside the system to ensure no residual pressure.

2.Loosen the clamp: Use a tool to loosen the bolts and remove the clamp.

3.Separate components: Pry apart the flanges and take out the sealing ring.

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