Ferrotec, Solid Shaft Ferro-Magnetic Fluid Rotary Feedthroughs

CF Flanged Solid Shaft

Designed to provide rotary motion under high vacuum, these ferrofluid feedthroughs have ConFlat-compatible (CF) mounting flanges. Normal helium leak detectors capable of detecting 1 x 10^-11 std cc/sec of Helium flow detect no leakage for CF mounts under static and dynamic testing. CF flanged rotary motion feedthroughs routinely operate in the 10^-6 torr range and, when properly prepared & installed, may be used to mid 10^-10 torr. ConFlat® Compatible (CF) Mounting Flanges

Baseplate Mount Solid Shaft

These ferrofluid rotary feedthroughs are sealed by a fluorocarbon o-ring. The operator mounts these drives to the vacuum chamber by screwing them into a corresponding threaded hole, or on some models by placing them in a suitable smooth-sided port in the chamber wall and using a capture nut. Some models are threaded only part way. They will accommodate various wall thicknesses when used with a sleeve or spacer over the unthreaded portion so that the nut compresses the o-ring.

In vacuum practice, the o-ring is compressed against the vacuum chamber’s inner surface to limit virtual leaks. As shown in the dimensional drawings, most ferrofluid feedthroughs are designed to be installed this way. A few, however, are intended to have the o-ring sealing against the air surface. To reduce the virtual leaks associated with the thread, the feedthrough has a flat machined along the length of its threaded portion.

Please refer to the technical notes about loading, temperature, and other relevant information before specifying a feedthrough.

O-Ring Flanged Solid Shaft

These Ferrofluidic^® rotary drives are designed for high vacuum applications where the chamber port has a flat, polished outer surface suitable for seating an o-ring surrounding a hole through the vacuum wall. Each feedthrough has a fluorocarbon o-ring installed in the flange. The flanges do not correspond to standard vacuum industry flange systems, however, the dimension table provides the information needed to mate to the chamber. Alternatively, we can supply an adapter spool piece to mate any feedthrough to a vacuum flange.

Thread Mount Solid Shaft

These ferrofluid rotary feedthroughs are sealed by a fluorocarbon o-ring. The operator mounts these drives to the vacuum chamber by screwing them into a corresponding threaded hole, or on some models by placing them in a suitable smooth-sided port in the chamber wall and using a capture nut. Some models are threaded only part way. They will accommodate various wall thicknesses when used with a sleeve or spacer over the unthreaded portion so that the nut compresses the o-ring.

In vacuum practice, the o-ring is compressed against the vacuum chamber’s inner surface to limit virtual leaks. As shown in the dimensional drawings, most ferrofluid feedthroughs are designed to be installed this way. A few, however, are intended to have the o-ring sealing against the air surface.To reduce the virtual leaks associated with the thread, the feedthrough has a flat machined along the length of its threaded portion.

Please refer to the technical notes about loading, temperature, and other relevant information before specifying a feedthrough.

Features

• Use a special magnetic fluid (ferrofluid) in place of an o-ring seal around dynamic parts
• Fluid hermetically seals the shaft making a liquid o-ring while a permanent magnet keeps the fluid in place
• Ferrofluid magnetically held in stages formed by grooves machined into either the shaft or pole pieces
• Unlike regular o-rings, the ferrofluid o-ring remains intact for years of operation despite the shaft’s motion

Applications

• Rotary stages
• Barrels
• Platens
• Planetaries
• Web coater rollers used in thin film deposition and etching processes