Features And Materials Of Nwkf Bolt-type Two-piece Vacuum Clamps

A NW‑KF bolted two‑piece vacuum clamp with 304 stainless steel body seals ISO‑KF flanges from vacuum to 10 bar. The clamp applies even O‑ring compression, eliminating leak paths. Available in sizes F16–F50 (3/4″–2″), temperature -20°C to 150°C. Meets 3‑A, DIN, and SMS standards.

The Micro‑Leak Threat in Sterile Processes

Biopharmaceutical processes rely on absolute vacuum integrity. A micro‑leak admits atmospheric moisture, oxygen, or contaminants — ruining cell cultures, degrading products, and triggering batch rejection. Threaded or bolted flanges loosen over time. A kf clamp maintains consistent sealing force through its bolted two‑piece design.

Micro‑leak sources eliminated:

• 🔧 Uneven flange compression

• ⚙️ O‑ring extrusion from pressure cycling

• 🔩 Thread galling and loosening

• 🧪 Contaminant ingress through gaps

• 🚫 Product loss from vacuum decay

How the KF Clamp Prevents Leaks

The KF clamp consists of two hinged halves that encircle flange ends with a centering ring and O‑ring between them. Tightening the wing nut draws the halves together, compressing the O‑ring evenly around the entire circumference. The two‑piece bolted design ensures consistent clamping force, eliminating uneven pressure. Meets ISO 2681 for interchangeability.

Key design features:

1. Two‑piece bolted construction for consistent force

2. Wing nut for tool‑free tightening

3. Uniform 360° O‑ring compression

4. Self‑centering flange alignment

5. Compatible with all ISO‑KF flanges

Material and Surface Finish

The clamp body is 304 stainless steel, machined from solid bar stock — no casting porosity. Resists corrosion and maintains strength under thermal cycling. O‑ring materials: EPDM, silicone, or FKM. Sizes: F16–F50 (3/4″–2″). The kf25 clamp fits 3/4″–1″ lines; the kf40 clamp fits 1″–1‑1/2″; the kf 50 clamp fits 1‑1/2″–2″; the kf 16 clamp suits small instrumentation lines. Complies with 3‑A, DIN, and SMS standards.

Specifications and Selection Criteria

Applications and Selection Considerations

The kf clamp is used in bioreactor vacuum lines, freeze‑dryer connections, sterile transfer lines, vacuum filtration, and pharmaceutical transfer.

When selecting:

• Size — F16 for small lines; F25 for process gas; F40 for main manifolds; F50 for high‑flow.

• O‑Ring — EPDM for general; silicone for high‑temp; FKM for aggressive chemicals.

• Pressure — vacuum to 10 bar.

• Standards — 3‑A, DIN, SMS ensure system compatibility.

Rapid assembly and disassembly for cleaning. Two‑piece design withstands repeated cycles.

Installation and Maintenance

Install centering ring and O‑ring between flanges. Position clamp halves, tighten wing nut — no tools. Disassemble by loosening wing nut. Inspect O‑rings every 6‑12 months. Supports autoclaving and SIP without disassembly. The kf25 clamp, kf40 clamp, kf 50 clamp, and kf 16 clamp all follow the same procedure.

This clamp design eliminates micro‑leak risks in biopharmaceutical vacuum systems. The NW‑KF bolted two‑piece clamp delivers reliable, tool‑free connections with consistent sealing force, maintaining sterility and process integrity.

NW KF Blot 2-part Vacuum Clamp

The KF Hardware (also known as NW) assembly consists of two flanges, a center ring and an stainless steel clamp. The quick clamp is assembled with a wing nut, ensuring easy tool-less use for long-term use. Applying even pressure on the clamp ensures a vacuum seal. The mating flange surface compresses the O-ring, which is held in place by a metal centering ring to create a vacuum seal.

Product Description

Product Parameter