1 Complete Model & Code Explanation

Model：NJ 202 ECP

Code Definition

NJ：Single row cylindrical roller bearing with double flanges on outer ring, single flange on inner ring for one-way axial positioning

202：Size series designation

EC：Optimized roller profile to reduce edge stress and improve anti-pitting capacity

P：Glass fiber reinforced polyamide injection molded cage

Clearance suffix: No suffix = CN standard normal radial clearance

Structure: Separable inner & outer rings; native one-way axial limit with minor axial displacement

Supply form: Complete finished bearing; optional HJ202EC angle ring for bidirectional positioning

Important reminder: NJ 202 ECP inherently withstands axial load only in one single direction, no reverse restriction. HJ202EC angle ring is mandatory for bidirectional positioning. Continuous maximum operating temperature for polyamide cage ≤120℃; brass cage variant recommended for sustained high temperature service. Apply pressing load on ring end surface, never transmit force through rolling elements to avoid cage fracture. Maximum allowable axial displacement 1 mm; not suitable for floating ends requiring large thermal expansion compensation.

Basic Parameters

Bore d：15 mm

Outer diameter D：35 mm

Width B：11 mm

Minimum chamfer r₁,₂：0.6 mm

Minimum chamfer r₃,₄：0.3 mm

Inner ring shoulder diameter d₁≈21.9 mm

Outer ring shoulder diameter D₁≈27.7 mm

Inner ring raceway diameter F=19.3 mm

Max permissible axial displacement s：1 mm

Basic dynamic load rating C：12.5 kN

Basic static load rating C₀：10.2 kN

Reference speed：22000 r/min

Limiting speed：26000 r/min

Material：High carbon chromium bearing steel

Cage：Glass fiber reinforced polyamide cage

Radial clearance：CN standard clearance

Net weight：0.048 kg

Indicative carbon footprint：0.11 kg CO₂e

eClass code：23-05-09-01

UNSPSC code：31171505

Combination Scheme

NJ202ECP + HJ202EC = NH202ECP (Cylindrical roller bearing unit with bidirectional axial locating)

2 Structure & Operating Characteristics

Japan NMT NJ 202 ECP features integrated double flanges on outer ring and single flange on inner ring. Separable rolling assembly equipped with polyamide cage. The single inner ring flange delivers one-way axial restriction, while retaining up to 1 mm small axial sliding clearance to absorb minor thermal elongation and prevent seizure.

EC optimized roller geometry relieves stress concentration on raceway edge and delays pitting failure. Lightweight polyamide cage provides low friction and quiet operation at medium-high rotating speed. The bearing primarily carries radial loads and moderate one-way axial loads; not recommended for heavy alternating bidirectional axial impact. Normally applied as the locating fixed bearing, paired with NU floating bearing in transmission systems.

3 Core Performance Advantages

1. EC optimized roller design reduces edge loading, raising load rating and raceway durability.

2. Glass fiber reinforced polyamide cage ensures smooth rotation, lower vibration and noise under medium-high speed.

3. Native NJ one-way locating structure simplifies shaft design for single-direction axial restriction without extra spacer rings.

4. Separable inner and outer rings facilitate disassembly, inspection and individual spare part replacement.

5. Standard CN radial clearance fits most normal-temperature general transmissions with easy selection.

6. Compatible with HJ202EC angle ring for flexible upgrade to bidirectional positioning, supporting multiple shaft layout schemes.

4 Typical Application Fields

4.1 Power Drive Equipment

Locating end support for small three-phase asynchronous motors, variable frequency motors

4.2 Reduction Transmission Systems

High-speed shaft locating pivot of small gear reducers and worm reducers

4.3 Fluid Machinery

Main shaft support for centrifugal fans, blowers and small air compressors

4.4 Light Industry General Machinery

Textile machinery, packaging equipment, light belt conveyor transmission mechanisms

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

Keep assembly surface clean without metal debris; prevent roller scattering and collision while separating rings. Apply pressing force evenly on flat ring end faces; avoid striking rollers and cage. Maximum mounting temperature ≤120℃; open flame heating forbidden to protect polyamide cage. After installation verify effective one-way limit and smooth minor axial sliding.

5.2 Selection Guidance

Only one-way axial positioning required, minor thermal expansion compensation → select NJ202ECP directly

Bidirectional axial restriction needed → match HJ202EC angle ring for NH configuration

Continuous working temperature persistently above 120℃ → switch to brass cage version

Large shaft thermal elongation requiring wide axial compensation → choose NU202ECP floating bearing

5.3 Lubrication Maintenance Instruction

Compatible with lithium grease and circulating oil lubrication. Perform low-speed no-load running-in for 2~4 hours after initial startup. Replenish lubricant periodically to eliminate dry friction and cage overheating damage.

5.4 Environmental Application Notes

Polyamide cage lacks resistance to acid, alkali and continuous high temperature. Install housing sealing for dusty and humid environments. Auxiliary shaft lock nut is recommended to share axial load under frequent axial impact.

6 Daily Maintenance & Fault Troubleshooting

Conduct no-load running-in after assembly, monitor temperature rise, vibration and abnormal noise. Common failure modes: raceway fatigue spalling, roller edge pitting, cage abrasion & fracture, flange scuffing.

Typical failure causes: improper assembly force, excessive heating temperature, insufficient lubrication, axial impact overload, hard foreign particles trapped in raceway. Bearings with broken cage, extensive spalling or severe flange scuffing cannot be repaired and require direct replacement.