Sprag Clutches for Helicopter Transmission Systems

GMN Bearing USA’s ABEC 7 high precision ball bearings are made for high speed and heavy load applications.

GMN angular contact bearings (spindle bearings) are expertly crafted for speed, precision, & accuracy.

GMN radial ball bearings are versatile, great in small spaces & when axial loads move in both directions.

We know that not every application requires super, high-precision bearings. We stock other industrial parts from quality brands.

Our one-way sprag clutches are great for applications with low to high torque capacity.

Includes built-in ball bearing support. Supports HEAVY loads & has a high torque capacity: 53 to 588 Nm. Bore (ID) sizes: 10 to 60 mm (0.393 to 2.362 in)

Includes built-in ball bearing support. Supports MEDIUM loads & low to medium torque capacity: 53 to 267 Nm. Bore (ID) sizes: 17 to 40 mm (0.669 to 1.57 in)

No built-in ball bearing support. Good for large orders & low to high torque needs: 1 to 2673 Nm. Bore (ID) sizes: 2 to 240 mm (0.078 to 9.448 in)

No built-in ball bearing support. Has no RPM limits & Supports high torque needs: 609 to 14,060 Nm. Bore (ID) sizes: 38.09 to 220 mm (1.499 to 8.66 in)

This heavy-duty clutch (aka a hold-back clutch) is good for high torque operations and ensures motion freezes in place. Bore (ID) sizes: 15 to 40 mm. (0.59 to 1.73 in)

Designed for HEAVY-DUTY applications that require tough durability.

Our non-contact labyrinth seals are the first line of protection for bearing systems.

The best protection for your bearing. Easy to install with a simple “drop-in” next to your bearing. No added space needed. CF seals offer 100% sealing efficiency against splashing liquids.

Protection against low contamination & splashing liquids.

Designed with grooves in the outer ring to offer more protection (than our L-type seal) against contamination and direct spray liquids. Liquid gets pushed out through outer grooves when in rotation.

Our GMN Gap Seals are plastic and a great choice for washdown applications, such as food conveyors and food manufacturing facilities

Safety is #1 with German-made GMN Sprag Clutches

One of the most critical components in rotorcraft systems is the humble, but intricately designed & manufactured sprag clutch.

A sophisticated mechanical part, a sprag clutch enables aircraft (like helicopters), to engage in a vital safety function called autorotation. Through a freewheeling action, sprag clutches allow for safe landings in the catastrophic event of engine failure or tail-rotor failure.

How A Helicopter Sprag Clutch Works

GMN clutch animation GIF

Autorotation disengages the engine from the main rotor and employs a freewheeling clutch that allows the rotors to continue to rotate without any drag from the engine. This life-saving action allows a pilot to guide the craft back to a secure location without manual manipulation.

Why GMN FE 8000 Sprag Clutches are #1 for Rotorcrafts

Here’s where GMN Sprag Clutches, particularly the FE 8000, have proven themselves to be an industry game-changer:

GMN FE 8000 Sprag Clutch

FE 8000 Clutches Have Double the Torque Capacity

Through a unique, single-cage design, German-made GMN FE 8000 clutches feature more sprags than any other clutch in today’s market & are commonly crossed with various other clutch manufacturers. This key characteristic means GMN sprag clutches consistently have up to double the torque capacity. This equivalates to possibly using a smaller size clutch for your torque needs. And more torque could mean a higher safety factor for your helicopter design.

FE 8000 Clutches Have No RPM Limit

GMN’s distinctive geometric design of the cam sprag is a “non-lift-off design.” At a high rotation speed, centrifugal force will produce a pressing torque on the sprags, no matter how fast the spooling speed. This means there are no RPM limits!

FE 8000 clutches have a unique angle of twist, resulting in high, nearly instantaneous engagement. For GMN clutches, the twisting angle is typically under 3° for nominal torque values, but if the torque is small that twisting angle can be close to 0°. Relative to other clutch mechanisms, even 3° is considered quite low.

FE 8000 Clutches Are Designed for Less Wear

Some sprag manufacturers use drag clips to prevent the sprags from rotating too fast and lifting off. This creates extra wear on the inner sprag surfaces. Because GMN sprags don’t have to worry about lift off, there is no need for drag clips, resulting in much less friction & deterioration.

And something else? GMN FE 8000 Sprag Clutches are drop-in replacements for many discontinued clutches from brands such as BorgWarner, Ringspann, Formsprag & others. This means there is no need for a system redesign.

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Check out this handy FE 8000 clutch cross-reference chart for a list of hard-to-find parts & their GMN alternatives.

Learn more about how GMN Bearing USA is #1 in German Manufacturing, Design, & Safety!

GMN Bearing USA comes through in the Clutch for Helicopter Transmission Systems