KF Vacuum Flanges - Quick Connect, Standardized NW Sizes

Vacuum KF Blank Flanges Vacuum Fittings KF16-KF50

Blank flanges are round flanges, usually with a flat surface and no opening in the center, used to close off pipe or cavity connections in vacuum systems.

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Vacuum KF/NW bored flanges KF16-KF50 SS304/SS316L

Ruijia High Vacuum Flanges including KF/NW vacuum blank flange,bored flange, ISO vacuum blank flange and CF blank flange.

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Why choose us

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.

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What international standards do your products meet?

Compliant with SEMI, ASME BPE, ISO 286; RoHS/REACH test reports available.

What is the lifespan of vacuum bellows?

Standard: ≥500K cycles (±10% stroke); Reinforced: ≥1M cycles.

Do your products meet semiconductor cleanliness standards?

Yes, compliant with ASTM E595 outgassing, particles ≤ISO Class 4.

How to adapt between flange standards (e.g., CF to KF)?

Dedicated adapters (with seals) for 20+ combinations like CF-KF/CF-ISO.

What surface finishes are available for vacuum chambers?

Machine polish (Ra0.8μm), Electropolish (Ra0.4μm), Passivation (anti-oxidation).

News

KF Clamp Tightening: How Much Torque Is Actually Enough?

Determining adequate tightening torque for ISO-KF clamp connections, with size-based reference ranges and practical “eno...

2026-10-23

KF25 vs KF40 vs KF50: Selecting by Pump Speed and Line Length, Not Just Similar Inner Diameter

Selecting among KF25, KF40 and KF50 quick-connect flange sizes by evaluating how line conductance limits effective pumpi...

2026-10-19

Why KF Quick-Connect Fittings Are So Widely Used in Modular Vacuum Systems

Learn why KF quick-connect fittings are widely used in modular vacuum systems. Compare KF with ISO and CF flanges, revie...

2026-10-10

Why KF Seals Fail: Centering Ring & O-Ring Guide

Most KF vacuum seal failures trace back to the centering ring or O-ring — not the clamp. Learn how to select, match, and...

2026-09-30

After-Sales Service

We have a modern stock management system and professional after-sales service team.

Rich stock, fast delivery

Quick response within 24h

Quality assurance

Accessory replacement