
GMN
Frequently asked questions
Common questions about GMN from 3G Electric.
What precision class do GMN angular contact bearings typically meet?
GMN super-precision angular contact bearings in the KH and S series are manufactured to ABEC P4 tolerance class, which corresponds to ISO P4. This precision level specifies tight dimensional and running accuracy tolerances, making these bearings suitable for high-speed spindles and other applications where minimal vibration and consistent preload are required. The ABEC P4 rating is verified through inspection and testing during production.
Are GMN sprag clutches available in different bore sizes?
Yes, GMN ball-bearing-supported sprag clutches in the FP and FPD series are offered with bore sizes ranging from 20 mm to 50 mm. For example, the FPD 432-Z has a 20 mm bore, while the FP 463-M has a 50 mm bore. Static torque ratings vary accordingly, from 89.2 ft-lb to 340 ft-lb. These clutches are designed for overrunning, indexing, and backstopping applications in industrial drives.
Can GMN angular contact bearings be ordered as matched duplex pairs?
Yes, GMN offers matched duplex angular contact bearings in the KH and S series, such as the KH 6008 and S 61806. These are supplied as a single pair (1 PR) with preload and axial clearance matched to ensure consistent performance in back-to-back or face-to-face mounting arrangements. Duplex sets are commonly used in machine tool spindles where axial rigidity and load sharing are critical.
What cage materials are used in GMN super-precision bearings?
GMN super-precision angular contact bearings typically use phenolic resin cages, as seen in models like the KH 6001 and KH 61901. Phenolic cages are lightweight, have low thermal expansion, and provide good wear resistance at high speeds. They are standard for applications requiring reduced inertia and stable cage guidance under varying operating conditions.
Are GMN clutches suitable for backstopping applications?
Yes, GMN sprag clutches in the FP and FPD series are designed for overrunning, indexing, and backstopping. The sprag design allows free rotation in one direction and locks in the opposite direction, making them suitable for preventing reverse rotation in conveyor systems, elevators, and other machinery where backstopping is required. Static torque ratings up to 340 ft-lb are available.
What contact angles are available for GMN angular contact bearings?
GMN angular contact bearings are available with contact angles of 15°, 17°, and 25°. For example, the S 61806 has a 15° contact angle, the KH 6001 has a 17° angle, and the KH 6008 has a 25° angle. The contact angle affects axial load capacity and speed capability; higher angles provide greater axial load capacity, while lower angles are optimized for higher speeds.
