Single row four point contact ball slewing bearing (Q series)

Q series single row four point contact ball slewing bearing is a compact, lightweight and high-precision slewing ring widely applied for light and medium-duty rotary equipment. Adopting Gothic arch four-point contact ball structure, this turntable bearing can simultaneously bear axial load, radial load and tilting moment, achieving stable rotary performance with simple installation and long service life

Product Description

Single Row Four Point Contact Ball Slewing Bearing (Q Series) - Precision Engineered for Multi-Load Applications

The Single row four point contact ball Slewing Bearing (Q series) represents a specialized rotary solution for light and medium-duty equipment requiring simultaneous support of axial, radial, and tilting moment loads. This compact slewing bearing utilizes a Gothic arch four-point contact ball structure, where steel balls contact the hardened raceway slewing bearing surfaces at four distinct points under zero load conditions, transitioning to two effective load-carrying points during operation. This configuration delivers superior load distribution across all three axes while maintaining a reduced vertical profile compared to multi-row alternatives. Precision-manufactured with P0 to P4 accuracy grades, the Q series achieves rotation with minimal friction and extended service life through optimized contact geometry.

Technical Structure & Operating Principle

The Q series employs a single-row ball complement arranged within specially profiled inner and outer ring raceways. Unlike conventional deep groove bearings, the Gothic arch raceway curvature enables each ball to establish contact at two points on the inner race and two points on the outer race simultaneously. This four-point contact mechanism distributes combined loads efficiently while minimizing contact stress concentration.

The heat treated slewing bearing structure includes precision-machined mounting holes in both rings for direct bolted attachment to adjacent structures, eliminating the need for separate housing components. A double seal slewing ring configuration incorporates dual sealing elements—typically labyrinth seals combined with rubber lip seals—to prevent lubricant leakage and block ingress of contaminants such as dust, moisture, and abrasive particles.

Raceway surfaces undergo controlled induction hardening to achieve 55-62 HRC surface hardness while maintaining ductile core properties. This hardened raceway slewing bearing processing enhances wear resistance and rolling contact fatigue strength, critical for applications with frequent directional changes or continuous rotation cycles.

JB/T10839-2008 standard slewing bearing numbering method

Explanation: 1. The dimensions of the No gear (QU) series are composed of Internal gear D and External gear dn with the same raceway center diameter, and The plug position and oil holes are arranged on the outer ring.
Mounting and connection hole type code
Inner and outer rings are unthreaded holes.
The base of the inner and outer rings are threaded holes with a depth of T (the mounting hole thread T can be at the other end of the hole).
The base of outer rings is threaded holes with a depth of T, the inner ring is the unthreaded hole (the mounting hole thread T can be at the 　　　other end of the hole).
The base of innerring is threaded holes with a depth of T, the outer rings is the unthreaded hole (the mounting hole thread T can be at the 　　　　other end of the hole).
The External gear type (QW) structure diagram, the Internal gear type (QN) structure diagram and the No gear (QU ) structure diagram are as follows:

轴承型号Bearing type	外形尺寸 Boundary dimensions					安装孔尺寸 Mounting hole diameter						结构尺寸Structure dimensions		齿轮参数 Gear parameters
QW,QN,QU 系列 QW,QN,QU series	外齿式 External gear type		内齿式Internal gear type		H	Du	Dn	n	通孔Through hole A型	螺孔 Screw holes B,C,D型		n1 油杯数量Number of oil holes	h	b	m模数Modulus	外齿式 External gear type			内齿式 Internal gear
																X=-0.5			x=+0.5
	D	dn	D	d					Φ	d1	T					De	Z	质量Mass	de	Z	质量Mass
	mm					mm			mm				mm	mm		mm		kg	mm		kg
280.16	360	198	360	200	60	328	232	10	15	M14	28	2	10	44	3.5	385	109	29	178.5	52	27
280.16A															4	388	96	29	176	45	27
315.16	395	233	397	235	60	363	267	12	15	M14	28	2	10	44	3.5	423.5	120	34	213.5	62	31
315.16A															4	424	105	34	212	54	31
355.16	435	273	437	275	60	403	307	12	15	M14	28	2	10	44	3.5	458.5	131	37	252	73	34
355.16A															4	460	115	38	252	64	34
400.16	480	318	482	320	60	448	352	12	15	M14	28	2	10	44	3.5	504	143	45	297.5	86	42
															4	504	125	46	296	75	43
400.16A
450.16	530	368	532	370	60	498	402	12	15	M14	28	2	10	44	3.5	553	157	51	346.5	100	50
															4	556	138	52	344	87	51
450.16A
450.20	544	354	546	354	70	508	392	12	17	M16	30	2	10	50	4	572	142	65	328	83	62
450.20A															5	570	113	64	325	66	62
500.20	594	404	596	404	70	558	442	14	17	M16	30	2	10	50	4	624	155	74	376	95	70
500.20A															5	625	124	74	375	76	70
560.20	654	464	656	468	70	618	502	14	17	M16	30	2	10	50	4	680	169	78	440	111	76
															5	685	136	79	435	88	77
560.20A
630.20	724	534	726	538	70	688	572	16	17	M16	30	2	10	50	4	748	186	86	512	129	84
630.20A															5	755	150	88	505	102	86
710.20	804	614	806	618	70	768	652	18	17	M16	30	2	10	50	5	835	166	99	585	118	97
710.20A															6	840	139	101	582	98	97
800.20	894	704	896	708	70	858	742	20	17	M16	30	2	10	50	6	930	154	114	672	113	110
800.20A															8	936	116	114	664	84	111
630.25	734	522	738	522	78	694	566	16	22	M20	36	2	10	58	5	770	153	113	490	99	107
630.25A															6	774	128	114	486	82	107
710.25	814	602	818	602	78	774	646	18	17	M20	36	2	10	58	6	858	142	131	564	95	122
710.25A															8	864	107	132	560	71	122
800.25	904	692	908	694	78	864	736	18	22	M20	36	2	10	58	6	942	156	143	654	110	142
800.25A															8	952	118	147	648	82	142
900.25	1004	792	1008	794	78	964	836	20	22	M20	36	2	10	58	8	1048	130	162	744	94	163
900.25A															10	1060	105	168	740	75	162
1000.25	1104	892	1108	894	78	1064	936	24	22	M20	36	2	10	58	8	1152	143	182	848	107	178
1000.25A															10	1160	115	185	840	85	179
1120.25	1124	1012	1228	1014	78	1184	1056	28	22	M20	36	2	10	58	8	1280	159	213	968	122	197
1120.25A
															10	1280	127	210	960	97	201
800.32	920	676	924	680	90	874	726	18	24	H22	40	2	10	70	8	976	121	211	632	80	196
800.32A															10	980	97	212	630	64	195
900 32	1020	776	1024	780	90	974	826	20	24	M22	40	2	10	70	8	1072	133	235	720	91	229
900.32A															10	1080	107	239	720	73	227
1000.32	1120	876	1124	880	90	1074	926	24	24	M22	40	2	10	70	8	1160	144	227	832	105	230
1000.32A															10	1170	116	232	830	84	227
1120.32	1240	996	1244	1000	90	1194	1046	28	24	M22	40	4	10	70	10	1300	129	272	940	95	263
1120.32A															12	1308	108	275	936	79	262
1250.32	1370	1126	1374	1130	90	1324	1176	32	24	M22	40	4	10	70	10	1430	142	302	1070	108	294
1250.32A															12	1440	119	309	1068	90	290
1400.32	1520	1276	1524	1280	90	1474	1326	36	24	M22	40	4	10	70	12	1584	131	337	1212	102	333
1400.32A															14	1596	113	347	1204	87	336
900.40	1040	758	1044	760	102	986	814	20	26	M24	45	4	12	80	10	1100	109	304	700	71	288
900.40A															12	1104	91	305	696	59	289
1000.40	1140	858	1144	860	102	1086	914	24	26	M24	45	4	12	80	10	1200	119	336	800	81	321
1000.40A															12	1212	100	347	792	67	324
1120.40	1260	978	1264	980	102	1206	1034	282	26	M24	45	4	12	80	10	1320	131	374	920	93	359
1120.40A															12	1332	110	386	912	77	363
1250.40	1390	1108	1394	1110	102	1336	1164	32	26	M24	45	4	12	80	10	1450	144	396	1050	106	388
1250.40A															12	1452	120	392	1044	88	388
1400.40	1540	1258	1544	1260	102	1486	1314	36	26	M24	45	4	12	80	12	1608	133	448	1188	100	444
1400.40A															14	1610	114	443	1190	86	434
1600.40	1740	1458	1744	1460	102	1686	1514	40	26	M24	45	4	12	80	12	1812	150	528	1392	117	509
1600.40A															14	1820	129	534	1386	100	511
1800.40	1940	1658	1944	1660	102	1886	1714	44	26	M24	45	4	12	80	14	2016	143	583	1582	114	576
1800.40A															16	2032	126	607	1568	99	591
2000.40	2140	1858	2144	1960	102	2086	1914	48	26	M24	45	4	12	80	14	2226	158	714	1778	128	675
2000.40A															16	2224	138	727	1776	112	673
1250.50	1412	1084	1416	1088	124	1354	1146	32	30	M27	50	4	12	100	12	1476	122	583	1008	85	581
1250.50A															14	1484	105	592	1008	73	577
1400.50	1562	1234	1566	1238	124	1504	1296	36	30	M27	50	4	12	100	12	1632	135	665	1164	98	645
															14	1638	116	670	1162	84	643
1400.50A
1600.50	1762	1434	1766	1438	124	1704	1496	40	30	M27	50	4	12	100	12	1824	151	714	1368	115	714
1600.50A															14	1834	130	727	1358	98	723
1800.50	1962	1634	1966	1638	124	1904	1696	44	30	M27	50	4	12	100	14	2044	145	845	1568	113	794
1800.50A															16	2048	127	843	1552	98	818
2000.50	2162	1834	2166	1842	124	2104	1896	48	30	M27	50	6	12	100	16	2240	139	912	1760	111	891
2000.50A															18	2250	124	927	1746	98	913
2240.50	2402	2074	2406	2078	124	2344	2136	54	30	M27	50	6	12	100	16	2480	154	1020	1984	125	1044
2240.50A															18	2502	138	1078	1980	111	1041
2500.50	2662	2334	2666	2342	124	2604	2396	60	30	M27	50	6	12	100	18	2754	152	1171	2250	126	1132
2500.50A															20	2760	137	1175	2240	113	1148
2800.50	2962	2634	2966	2638	124	2904	2696	66	30	M27	50	6	12	100	18	3060	169	1393	2538	142	1361
2800.50A															20	3060	152	1382	2540	128	1344
3150.50	3312	2984	3316	2988.	124	3254	3046	72	30	M27	50	6	12	100	18	3402	188	1535	2898	162	1501
3150.50A															20	3420	170	1597	2880	145	1554
2000.60	2196	1804	2196	1808	150	2126	1874	48	33	M30	56	6	14	122	18	2304	127	1431	1710	96	1344
2000.60A															20	2320	115	1476	1700	86	1361
2240.60	2436	2044	2436	2048	150	2366	2114	54	33	M30	56	6	14	122	18	2538	140	1576	1944	109	1526
2240.60A															20	2540	126	1572	1940	98	1527
2500.60	2696	2304	2696	2308	150	2626	2374	60	33	M30	56	6	14	122	18	2790	154	1677	2214	124	1621
2500.60A															20	2800	139	1701	2200	111	1654
2800.60	2992	2604	2996	2608	150	2926	2674	66	33	M30	56	6	14	122	18	3078	170	1817	2502	140	1871
2800.60A															20	3100	154	1904	2500	126	1857
3150.60	3342	2954	3346	2958	150	3276	3024	72	33	M30	56	6	14	122	20	3440	171	2087	2840	143	2144
3150.60A															22	3454	156	2139	2838	130	2129
3550.60	3742	2354	3746	3358	150	3676	3424	78	33	M30	56	6	14	122	20	3840	191	2355	3240	163	2425
3550.60A															25	3875	154	2500	3225	130	2437
4000.60	4200	3804	4196	3808	150	4126	3874	80	33	M30	56	6	14	122	22	4312	195	2787	3696	169	2683
4000.60A															25	4325	172	2827	3675	148	2763
4500.60	4700	4304	3316	2988	150	4626	4374	86	33	M30	56	6	14	122	25	4825	192	3268	4175	168	3247
4500.60A															28	4816	172	3372	4172	150	3334

Key Performance Advantages

This multi-load slewing bearing can take axial, radial, and moment loads in a single compact assembly due to its four-point contact shape, minimising system complexity.

Low friction coefficient: Precision ball-to-raceway contact optimisation and specialised greases reduce rotational torque, making this turntable bearing appropriate for low-drive power applications.

Compact installation footprint: The single-row arrangement has a light-weight slewing ring with a lower axial height than double-row or crossed roller options, excellent for space-constrained applications.

Maintaining rotational accuracy throughout its service life, this high-precision slewing bearing supports precision positioning applications with machining tolerances of P6 or P5.

Environmental protection: The integrated double seal system blocks moisture and chemicals to make the slewing bearing corrosion-resistant for outdoor and maritime equipment.

Smooth operation: Controlled manufacturing tolerances and balanced ball complement arrangement provide a low-noise swing bearing with minimum rotational vibration.

Single row four point contact ball slewing bearing (Q series) factory

Technical Specifications

Parameter	Specification
Applicable Diameter Range	50-10,000 mm
Bearing Type	Single-row four-point contact ball
Raceway Configuration	Gothic arch profile
Precision Grades Available	P0, P6, P5, P4
Raceway Hardness	55-62 HRC (induction hardened)
Seal Configuration	Double seal (labyrinth + lip seal)
Load Capacity	Axial radial tilting moment slewing bearing - simultaneous multi-axis loading
Mounting Type	Through-bolt direct attachment (both rings)
Material Standard	High-strength bearing steel (42CrMo / 50Mn grade)
Operating Temperature Range	-30°C to +80°C (standard grease)
Surface Treatment Options	Zinc phosphate, black oxide, or customized anti-corrosion coating

Note: Specific load ratings and dimensions vary by model designation. Contact engineering for detailed capacity calculations.

Industry Applications

The Single row four point contact ball slewing bearing (Q series) serves as a light duty slewing bearing across diverse sectors:

Construction Excavator: Mini excavators, backhoe loaders, mobile cranes, truck-mounted cranes, tower cranes, aerial work platforms, road rollers, material handlers requiring compact rotary joints with multi-directional load support.

Industrial Automation: Welding manipulators, rotary welding tables, industrial robot bases, palletizing systems, packaging excavator, laser cutting platforms demanding high positioning accuracy and repeatability.

Renewable Energy Systems: Single-axis and dual-axis solar trackers, heliostats, concentrated solar equipment, small wind turbine yaw mechanisms where weight reduction directly impacts structural costs.

Entertainment & Display Equipment: Rotating stages, exhibition turntables, amusement rides, museum display platforms requiring smooth, quiet operation with minimal maintenance.

Logistics & Material Handling: Forklift rotary attachments, warehouse automation, small container spreaders benefiting from reduced weight and simplified integration.

Specialized Vehicles: Fire truck platforms, sanitation vehicle rotary arms, rescue equipment, yacht rotary mechanisms, offshore monitoring platforms operating in demanding environmental conditions.

Single row four point contact ball slewing bearing (Q series)

Addressing Critical Procurement Concerns

Compatibility Verification: For OEM replacement applications, our engineering team conducts 1:1 technical drawing review to ensure exact dimensional matching with existing equipment interfaces. Provide your current bearing markings or mounting dimensions for compatibility confirmation.

Delivery Timeline Management: The In Stock product ship within 7-15 days from stock. Custom setups take 4-6 weeks, depending on intricacy. Semi-finished component inventory enables flexible production scheduling to minimize your equipment downtime.

Application-Specific Engineering: Our team provides load calculation support, mounting configuration recommendations, and lubrication specification guidance tailored to your specific operating conditions—whether high-dust environments, temperature extremes, or continuous duty cycles.

Non-Standard Customization: When standard catalog dimensions don't match your requirements, we offer custom engineering based on your installation geometry, gear parameters, and load specifications—even without original manufacturer drawings through our on-site measurement and reverse engineering service.

Certification

Single row four point contact ball slewing bearing (Q series) certification

FAQ

Q: How does the four-point contact design improve load capacity compared to single-point contact bearings?

A: The four-point geometry distributes loads across multiple contact patches simultaneously, reducing peak contact stress and enabling a single bearing to replace what would otherwise require separate axial and radial bearing assemblies.

Q: What maintenance intervals are recommended for Q series bearings?

A: Inspect seals every 500 operating hours; re-lubricate every 1,000-2,000 hours depending on load intensity and environmental exposure. Detailed maintenance procedures are provided with each shipment.

Q: Can you supply bearings for existing equipment without original drawings?

A: Yes. Our on-site measurement service captures critical dimensions from installed bearings, enabling precise reproduction with optimized design improvements where beneficial.

Q: What accuracy grade should I specify for precision positioning applications?

A: P5 grade is recommended for most automated positioning systems; P4 grade for applications requiring exceptional concentricity and minimal runout, such as optical equipment bases.

Contact Us

You can verify dimensional compatibility, request load calculation assistance, or obtain technical specifications for your specific application of the Single row four point contact ball slewing bearing (Q series). Our engineering team at Luoyang Heng Guan Bearing Technology provides comprehensive support from selection through installation. Reach us at mia@hgb-bearing.com to discuss your requirements and access detailed product documentation.

WHAT OUR CUSTOMERS SAY

Here is the customer's evaluation of us

From Europe

As a leading construction machinery manufacturer in Europe, we are very impressed with the quality and performance of your slewing rings. The precision machining and consistent quality meet our strict standards. A reliable global supplier!

From United States

Our CT scanners require extremely smooth rotation, low noise, and no magnetic interference. Your product perfectly meets these requirements, operating virtually silently without compromising image quality. Your technical expertise is truly impressive!

From Southeast Asia

We have been the distributor of your brand for many years and have received excellent customer feedback. Your diverse product line meets diverse customer needs, and our consistent quality makes us very competitive in the market. Your technical support and service team are also fantastic!

From United States

The slewing bearing selected for our wind turbine main drive system has exceeded our expectations in terms of precision and reliability. It operates smoothly even in extreme wind conditions and has a long maintenance cycle, significantly reducing our lifecycle costs. We are a trustworthy partner!

From the Middle East

Our equipment required a slewing bearing with non-standard dimensions and special gears. We contacted several companies but they all said they couldn't make it. Not only did you accept the order, but we also communicated smoothly throughout the entire process from proofing to mass production, and the finished product fully met our design requirements. This customization capability demonstrates your true technical strength.

From Europe

We have integrated your slewing rings into our new line of crawler cranes. The performance under full load and in extreme weather conditions has been flawless. The precision and durability meet the highest European standards. A truly reliable component for critical applications.

From North America

The harsh, sandy environment of our port is a true test for any equipment. Your slewing bearings' superior sealing system has effectively kept out abrasive contaminants. Our ship-to-shore cranes have seen a dramatic increase in uptime and service life since switching to your brand.

From the Middle East

In the mining industry, equipment failure is not an option. The immense strength and robust construction of your large-diameter slewing bearings have withstood the incredible shocks and loads in our mining excavators. Their reliability is directly contributing to our productivity.