FAG 6330-M-C3 Deep Groove Ball Bearing

FAG 6330-M-C3 Deep Groove Ball Bearing (150 mm x 320 mm x 65 mm)

The FAG 6330-M-C3 is a single-row radial deep groove ball bearing engineered by Schaeffler to operate under severe thermal gradients, high radial stresses, and sustained axial loads. Featuring a 150 mm bore, 320 mm outer diameter, and a 65 mm width, this heavy-series bearing integrates a machined solid brass cage (M) guided by the rolling elements and an increased radial internal clearance (C3).

The 6330-M-C3 withstands heavy rotational inertia, cyclic shock loads, and high peripheral velocities without cage fracture or thermal seizure. Its deep, uninterrupted raceway grooves provide optimal contact geometry for both pure radial loads and combined reversing thrust loads in either direction.

Model Details

• Manufacturer: Schaeffler Technologies AG & Co. KG (FAG)
• Part Number (MPN): 6330-M-C3
• Product Code / EAN: 4012801183185 / 6330.M.C3
• Suffix Designation:
  • M: Solid brass cage, ball-guided (two-piece, riveted/bolted)
  • C3: Radial internal clearance greater than Normal (68 to 98 µm)

Technical Details

Key Features

1. Machined Solid Brass Cage (M): Delivers superior fracture resistance, high thermal conductivity, and dampening properties against vibration and rapid acceleration compared to pressed sheet-steel cages.
2. C3 Radial Clearance Class: Accommodates significant thermal shaft expansion and heavy interference fits common in high-output marine machinery and heavy continuous-duty electric motors.
3. Optimized Deep Raceways: High-conformity raceway profile supports high-speed stability and substantial two-way axial loading without requiring secondary thrust arrangements.
4. Thermal Dimension Stability: Heat-stabilized raceways and rolling elements capable of continuous operating temperatures up to +200°C (+392°F).

Applications

• Marine Propulsion & Auxiliaries: Main engine turning gear drives, intermediate line shaft support blocks, tunnel thrusters, and ballast/cargo pump drive pedestals.
• Large Electrical Machinery: High-voltage induction motors (frame sizes 450–630), main propulsion slip-ring motors, synchronous ship-service alternators, and turbogenerator non-drive/drive end supports.
• Turbomachinery & Compressors: High-volume axial mine-ventilation fans, induced-draft (ID) boiler fans, multi-stage centrifugal blowers, and screw compressor rotor assemblies.
• Heavy Industrial Processing: Slag crushers, horizontal ball mill countershafts, vibratory screens, continuous steel caster roll pinions, and high-torque planetary reducers.

Compatible Equipment Assemblies

• ABB Marine & Turbocharging: HXR/M3BP 450–560 Series Heavy Marine Auxiliary Motors
• Siemens: SIMOTICS HV Series / 1LA8, 1LG4 Large Frame AC Induction Motors
• Framo / Svanehøj: Marine Deepwell Cargo Pumping Systems (Deck-Mounted Drive Pedestals)
• Sulzer / Flowserve: Multi-stage high-pressure boiler feed pumps and petrochemical horizontal slurry pumps
• Flender / SEW-Eurodrive: Heavy-duty parallel shaft industrial gear units (Sizes 15 through 22)

Frequently Asked Questions

What does the “M” suffix signify on the FAG 6330-M-C3 bearing?

The “M” designation identifies a two-piece solid machined brass cage guided by the rolling elements (balls). Machined brass cages offer far higher strength, shock loading resistance, and thermal durability than standard pressed-steel cages (“J”), making them mandatory for high-vibration applications like marine auxiliary drives and large compressors.

Why is C3 radial clearance required for this 150 mm bore bearing?

C3 indicates an internal radial play of 68 to 98 microns, which is greater than the standard (“Normal”) internal clearance. High-speed shafts expand outward as operating temperatures rise. The extra C3 clearance accommodates shaft heat expansion and heavy shaft press-fits without loading the rolling elements under zero-clearance conditions.

Can this bearing handle axial (thrust) loads?

Yes. Deep groove ball bearings have deep, uninterrupted raceway grooves conforming closely to the balls. As a result, the FAG 6330-M-C3 reliably supports combined radial and moderate bidirectional axial loads, even at high rotational speeds where external thrust washers cannot be deployed.

Can the FAG 6330-M-C3 bearing be greased, or does it require oil circulation?

The bearing is open (unsealed) and compatible with circulating oil systems, oil mist, oil bath splash systems, or grease injection systems. For grease setups, select an EP (extreme pressure) high-base oil viscosity grease (NLGI 2 or 3) with synthetic or mineral oil bases rated for dynamic operating temperatures up to at least 120°C.

How do I verify genuine Schaeffler FAG production?

Genuine FAG bearings feature laser-etched matrix codes, clean MPN etchings on outer and inner rings, and genuine Schaeffler OriginCheck security 2D barcodes on outer carton packaging to prevent counterfeit components from entering critical machinery supply chains.