Product Overview

Four-Point Contact Ball Bearings are specialized radial single-row angular contact ball bearings engineered with a split inner ring (or split outer ring) and gothic arch raceways. The unique gothic arch profile allows a single bearing ball to contact the raceways at four distinct points under light or zero axial load. When subjected to significant axial thrust in either direction, the contact transitions to a two-point contact system, enabling the bearing to support heavy bidirectional axial forces alongside moderate radial loads within a remarkably compact envelope.

Because one four-point contact bearing can replace a back-to-back or face-to-face pair of angular contact bearings, it significantly reduces total axial space and machine weight. Manufactured from high-cleanliness GCr15 Chrome Steel (or case-hardened alloys), these precision bearings are widely specified in industrial gearboxes, slewing drives, automotive transmissions, railway axle boxes, robot joint actuators, and agricultural steering assemblies.

Key Features & Advantages

Bidirectional Axial Load Capacity: Absorbs high axial thrust in both directions using a single bearing row, eliminating the need for paired duplex configurations.

Significant Space & Weight Savings: Takes up considerably less axial space than a two-bearing arrangement, simplifying housing design and reducing assembly footprint.

Separable Ring Construction: The split inner ring (QJ series) allows the outer ring with ball and cage assembly to be mounted separately from the inner ring halves, facilitating easy installation and maintenance inspection.

High Load Capacity & Rigidity: Gothic arch raceways optimize ball contact angles (typically 35°), providing high dynamic load ratings and structural stiffness under thrust loads.

Reduced Friction Under Axial Loads: Under predominant axial loading, two-point contact behavior maintains smooth rotation with minimal friction generation and low operational heat.

Model No.	Bore (d) [mm]	Outer Dia (D) [mm]	Width (B) [mm]	Contact Angle (α)	Dynamic Load (Cr) [kN]	Unit Weight [kg]
QJ 206	30	62	16	35°	31	0.22
QJ 208	40	80	18	35°	48	0.42
QJ 210	50	90	20	35°	58.5	0.54
QJ 212	60	110	22	35°	81.5	0.92
QJ 214	70	125	24	35°	100	1.3
QJ 308	40	90	23	35°	67	0.68
QJ 310	50	110	27	35°	98	1.2
QJ 312	60	130	31	35°	132	1.95
QJ 314	70	150	35	35°	176	3

FACTORY WORKSHOP

We continually invest in research and development to enhance our product offerings and manufacturing processes. Our goal is to maintain our position as a leader in the industry while embracing new technologies and trends that shape the future of metal production.

Factory workshop

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With a strong export network, Shandong Lu Tisco Stainless Steel Co., Ltd. serves clients across the globe. Our dedicated customer service team ensures that every client receives personalized attention, timely deliveries, and support throughout the product lifecycle.

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Four-Point Contact Ball Bearings