High-precision Deep Groove, Angular Contact & Cylindrical Roller bearings matched to your motor's exact thermal & acoustic specs. Test physical samples on your factory floor first with zero commitment before commercial orders.
One batch runs whisper quiet, while the next has acoustic resonance and radial play issues. Here is how BMT Impex locks in mechanical consistency.
We calibrate all motor-grade bearings to strict C3 internal radial clearances (13–28 µm), accommodating shaft thermal expansion without risking seizure.
Super-finished raceways (Ra ≤ 0.05 µm) and 100% Z3/V3 Anderometer noise inspection guarantee whisper-quiet operation under continuous rotation.
For frequency-inverter driven motors, we provide ceramic hybrid silicon nitride (Si₃N₄) ball configurations to completely block stray parasitic currents.
Filled with high-temp polyurea or synthetic ester lubricants rated for -40°C to +160°C, calibrated precisely at a 30–35% fill volume for minimal drag.
Equipped with 2RS contact synthetic rubber seals or 2RZ low-torque labyrinth non-contact shields to provide IP55/IP65 barrier protection.
We maintain locked safety buffer stock for our OEM clients, providing rapid JIT dispatch from our central inventory with zero lead time surprises.
Explore our specialized motor-duty bearing categories engineered for drive-end (DE) and non-drive-end (NDE) applications.
The primary workhorse for drive-end (DE) and non-drive-end (NDE) positions in fractional to multi-kilowatt motors. Supports high RPM with minimal frictional torque.
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Designed for vertical motor installations, submersible deep well pumps, and CNC spindles requiring rigid rotor location and combined radial/axial thrust support.
Fitted to the drive end (DE) of heavy 132+ frame motors, vibratory motors, and belt-pulley setups to carry heavy radial rotor overhang loads without deflection.
Select a category tab below to view boundary dimensions, dynamic load ratings (Cr), and limiting speeds.
| Bearing Model | Bore d (mm) | OD D (mm) | Width B (mm) | Dynamic Cr (kN) | Limiting RPM (Grease) | Typical Motor Frame | Action |
|---|---|---|---|---|---|---|---|
| 6204 2RS C3 | 20 | 47 | 14 | 12.8 | 15,000 | Frame 71 / 80 | |
| 6205 2RS C3 | 25 | 52 | 15 | 14.0 | 13,000 | Frame 80 / 90S | |
| 6206 2RS C3 | 30 | 62 | 16 | 19.5 | 11,000 | Frame 90L / 100L | |
| 6207 2RS C3 | 35 | 72 | 17 | 25.5 | 9,500 | Frame 112M | |
| 6208 2RS C3 | 40 | 80 | 18 | 29.1 | 8,500 | Frame 132S | |
| 6305 2RS C3 | 25 | 62 | 17 | 22.5 | 12,000 | Frame 90S / 90L (DE) | |
| 6306 2RS C3 | 30 | 72 | 19 | 28.1 | 10,000 | Frame 100L / 112M (DE) | |
| 6308 2RS C3 | 40 | 90 | 23 | 40.5 | 7,500 | Frame 132M (DE) | |
| 6310 2RS C3 | 50 | 110 | 27 | 62.0 | 6,000 | Frame 160M / 160L (DE) | |
| 6312 2RS C3 | 60 | 130 | 31 | 81.9 | 5,000 | Frame 180M / 180L (DE) |
| Bearing Model | Bore d (mm) | OD D (mm) | Width B (mm) | Contact Angle | Dynamic Cr (kN) | Limiting RPM | Action |
|---|---|---|---|---|---|---|---|
| 7205 B/BEP | 25 | 52 | 15 | 40° | 15.6 | 12,000 | |
| 7206 B/BEP | 30 | 62 | 16 | 40° | 22.1 | 10,000 | |
| 7208 B/BEP | 40 | 80 | 18 | 40° | 33.8 | 8,000 | |
| 7305 B/BEP | 25 | 62 | 17 | 40° | 26.0 | 11,000 | |
| 7308 B/BEP | 40 | 90 | 23 | 40° | 48.5 | 7,000 | |
| 7310 B/BEP | 50 | 110 | 27 | 40° | 72.0 | 5,600 |
| Bearing Model | Bore d (mm) | OD D (mm) | Width B (mm) | Cage Type | Dynamic Cr (kN) | Limiting RPM | Action |
|---|---|---|---|---|---|---|---|
| NU 208 ECP / ECM | 40 | 80 | 18 | Polyamide / Brass | 55.0 | 8,500 | |
| NU 210 ECP / ECM | 50 | 90 | 20 | Polyamide / Brass | 69.5 | 7,500 | |
| NU 308 ECP / ECM | 40 | 90 | 23 | Polyamide / Brass | 82.5 | 7,500 | |
| NU 309 ECP / ECM | 45 | 100 | 25 | Polyamide / Brass | 106.0 | 6,700 | |
| NU 311 ECP / ECM | 55 | 120 | 29 | Polyamide / Brass | 153.0 | 5,600 | |
| NU 312 ECP / ECM | 60 | 130 | 31 | Polyamide / Brass | 176.0 | 5,000 |
We never ask you to place a bulk purchase order blindly. Our 3-step qualification process is completely driven by your in-house QC sign-off.
Tell us your motor frame, expected RPM, radial clearance preference (CN/C3/C4), and cage/seal specifications.
We dispatch physical testing samples. Assemble them on your motor test bench, run acoustic decibel checks, vibration tests, and temperature rise evaluations.
Once your QC greenlights the samples, we lock those exact specifications into your account master sheet. You get identical performance batch after batch.
Sourced from ISO 9001 certified partner facilities and verified at our in-house testing lab before dispatch.
Calibrated electronic micrometers verify bore (d), outer diameter (D), and runout to sub-micron DIN/ISO standard tolerances.
100% dial-indicator gauge verification ensures true C3 internal radial play to prevent thermal expansion shaft binding.
Rockwell Hardness tester ensures through-hardened SAE 52100 vacuum-degassed chrome steel reaches HRC 60–65 for high fatigue life.
Decibel sound room & Anderometer vibration grading guarantees Z3/V3 low-noise compliance for whisper-quiet motor operation.
Technical and commercial clarifications for electric motor design and procurement engineers.
Yes, absolutely. We provide physical testing samples corresponding exactly to your required frame size, radial clearance (CN, C3, C4), cage material, and noise grade with zero commitment. You can mount them on your assembly test bench, test noise levels, vibration, and thermal rise before placing any commercial order.
During motor operation, the rotor shaft heats up faster than the motor housing end shields, creating a 20°C to 40°C thermal gradient. Standard (CN) clearance can cause the bearing to tighten and seize under thermal expansion. C3 clearance provides the necessary internal radial cushion to maintain optimal running clearance at operating temperatures.
Our motor-grade bearings are verified in our acoustic test facility to meet Z3/V3 and Z4/V4 low-vibration standards, ensuring whisper-quiet motor operation and elimination of end-of-line acoustic rejections.
Yes. Every commercial batch is supplied with complete Mill Test Certificates (MTC 3.1) and Certificate of Conformance (COC) confirming SAE 52100 chemical metallurgy, Rockwell hardness, dimensional calibration, and radial clearance measurements.
For motors controlled by Variable Frequency Drives (VFD), high-frequency stray currents can cause electrical fluting and micro-welding on bearing raceways. We provide ceramic hybrid silicon nitride (Si3N4) ball bearings and electrically insulated outer ring coatings that provide 100% galvanic isolation.
Request testing samples for your factory floor or speak directly with our motor application engineering team on WhatsApp.
© 2026 BMT Impex. All rights reserved. Sourced from ISO 9001 certified manufacturing facilities.