KF 90° Elbows: Reliable High-Vacuum Direction Changes

Product Description

KF 90° elbows are quick-flange vacuum fittings designed to redirect gas flow by 90 degrees in high-vacuum systems ranging from atmospheric pressure down to 10⁻⁸ Torr. Also known as NW 90° elbows, these components feature a 90-degree bend with smooth internal radii, KF flange connections on both ends, and vacuum-grade surface finishes to minimize outgassing and eliminate virtual leaks.

Manufactured from high-quality 304 or 316L stainless steel, KF 90° elbows are essential for vacuum chambers, pumping lines, foreline tubing, load locks, and analytical instruments. Each elbow incorporates the internationally standardized KF (Klein Flansch / Quick Flange) connection system, which uses a centering ring, elastomer O-ring, and wing nut clamp for rapid, tool-free assembly. Whether you are constructing a new vacuum manifold, modifying a deposition system, or repairing a leak detection station, these elbows deliver the conductance, reliability, and convenience that demanding high-vacuum applications require.

Key Features & Characteristics

• Bend Angle: 90 degrees (45° and custom angles also available)

• Connection Type: KF (NW) flanges on both ends (same size)

• Vacuum Range: Atmospheric to 1×10⁻⁸ Torr

• Bend Radius: Long radius (1.5× DN) – standard

• Material: 304 or 316L Stainless Steel

• Internal Surface Finish: Ra ≤ 0.8 µm (electropolished or mechanically polished)

• Outgassing Rate: < 2×10⁻⁸ Torr·L/s·cm² (after vacuum cleaning)

• Leak Integrity: Helium leak tested to < 1×10⁻⁹ mbar·L/s

• Bakeout Capability: Up to 150°C (with Viton® O-rings)

• Assembly: Tool-free clamping with KF clamps and centering rings

• Reusability: Fully demountable and reusable across multiple installations

Applications

• Vacuum pumping lines: Connecting roughing pumps to turbo pumps or chambers

• Foreline systems: 90-degree bends between backing pumps and high-vacuum pumps

• Instrumentation: Redirecting flow to pressure gauges and RGAs

• Thin-film deposition: Sputtering, evaporation, and ALD system plumbing

• Helium leak detection: Adapter lines between test ports and detectors

• Analytical instruments: Mass spectrometers, electron microscopes, surface analysis tools

• R&D vacuum manifolds: Compact 90-degree turns in multi-port arrangements

• Load lock systems: Interconnecting chambers with space-efficient layouts

Why Choose Our KF 90° Elbows?

We combine precision CNC tube bending with electropolishing and 100% helium leak testing to deliver KF elbows that meet or exceed international high-vacuum standards. Every elbow is ultrasonically cleaned with semiconductor-grade detergents, vacuum-bagged, and certified with a leak test report. Custom bend radii, reducing configurations, and special lengths are available with engineering support.