Double row cylindrical roller bearings are separable bearings. All the bearing units can be separately. This makes it easier to mount and dismount.
Double row cylindrical roller bearings have two structures of cylindrical and tapered bore. They mainly have 2 types: NN designs and NNU designs. Type of NN design has inner ring with two ribs and outer ring without rib. Type NNU has outer ring with two ribs and inner ring without rib. When mounting bearings with tapered bore, it is possible to reach a certain radial internal clearance. These two types of bearings allow axial displacements between shaft and housing, and can be used as non-locating bearings.
Double row cylindrical roller bearings have high load-carrying ability and high stiffness. The bearings are especially used as main shaft bearings of machine tools.

• They are mainly used in machine tools, rolling mill stands, plastic calenders, grinding mills and also large gearboxes.

• 

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  200	280	60	2.1	-	259	420	815	NN 3940	3282940	10.6
  	280	80	2.1	-	259	484	960	NN 4940K/W20	4182940Y	14.1
  	280	80	2.1	-	259	570	1220	NN 4940	4282940	15.3
  	280	80	2.1	225	-	570	1220	NNU 4940	4482940	15.3
  	310	82	2.1	-	282	655	1170	NN 3040	3282140	22.7
  	310	82	2.1	232	-	655	1170	NNU 3040	3482140	22.7
  	310	109	2.1	-	282	890	1730	NN 4040	4282140	30.4
  220	300	60	2.1	-	279	440	895	NN 3944	3282944	11.4
  	300	80	2.1	-	279	600	1330	NN 4944	4282944	16.6
  	300	80	2.1	245	-	600	1330	NNU 4944	4482944	16.6
  	340	90	3	-	310	815	1480	NN 3044	3282144	29.6
  	340	90	3	254	-	815	1480	NNU 3044	3482144	30
  	340	118	3	-	310	1190	2400	NN 4044	4282144	39.8
  	370	120	4	-	331	1050	1810	NN 3144	3282744	51.9
  	370	120	4	263	-	1050	1810	NNU 3144	3482744	52.3
  240	300	60	1.1	-	283	405	1030	NN 4848	4282848	9.77
  	300	60	1.1	259	-	358	930	NNU4848	-	9.9
  	320	60	2.1	-	300	460	975	NN 3948	3282948	12.2
  	320	80	2.1	-	300	625	1450	NN 4948	4282948	17.9
  	320	80	2.1	263	-	625	1450	NNU 4948	4482948	18
  	360	92	3	-	330	855	1600	NN 3048	3282148	32.7
  	360	92	3	274	-	855	1600	NNU 3048	3482148	32.7
  	360	118	3	-	330	1240	2600	NN 4048	4282148	39.3
  	360	118	3	274	-	1240	2600	NNU 4048	4482148	42.7
  	400	128	4	-	358	1170	2040	NN 3148	3282748	64.2
  	400	160	4	282	-	1880	3530	NNU 4148	4482748	85

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  260	360	75	2.1	-	335	670	1380	NN 3952	3282952	21.4
  	360	100	2.1	-	335	711	1540	NN 4952K	4182952	29.2
  	360	100	2.1	-	335	935	2100	NN 4952	4282952	28.3
  	360	100	2.1	292	-	935	2100	NNU 4952	4482952	31.1
  	400	104	4	-	364	969	1810	NN 3052K	3182152	47.1
  	400	104	4	-	364	969	1810	NN 3052	3282152	48.5
  	400	140	4	-	364	1550	3250	NN 4052	4282152	59.7
  	400	140	4	300	-	1550	3250	NNU 4052	4482152	65
  	440	144	4	-	393	1480	2660	NN 3152	3282752	89.1
  	440	180	4	306	-	2200	4000	NNU4152	4482752	113
  280	350	69	1.1	-	329	445	1160	NN 4856	4282856	15.3
  	350	69	2	303	-	457	1200	NNU4856K	-	15.5
  	380	75	2.1	-	355	695	1460	NN 3956	3282956	22.7
  	380	100	2.1	-	355	960	2230	NN 4956	4284956	32.9
  	380	100	2.1	312	-	960	2230	NNU 4956	4482956	33
  	420	106	4	-	384	1020	1950	NN 3056K	3182156	49.1
  	420	106	4	-	384	1020	1950	NN 3056	3282156	49.9
  	420	106	4	320	-	1080	2080	NNU3056	-	51.4
  	460	146	5	-	413	1520	2790	NN 3156	3282756	95.7
  300	380	80	2.1	324	-	690	1760	NNU 4860	4482860	21.7
  	420	118	3	-	388	1230	2870	NN 4960	4282960	51.6
  	420	118	3	339	-	1230	2870	NNU 4960	4482960	51.9
  	460	118	4	-	418	1180	2250	NN 3060	3282160	71.7
  	460	118	4	-	418	1180	2250	NN 3060K	3182160	69.6
  	460	160	4	-	418	1920	4100	NN4060	-	97.6
  	500	160	5	-	448	1760	3150	NN 3160	3282760	125
  	500	160	5	358	-	1760	3150	NNU 3160	3482760	126
  320	400	80	2.1	346	-	700	1840	NNU 4864	4482864	22.8

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  320	440	118	3	-	408	1260	3050	NN 4964	4282964	50.2
  	440	118	3	-	408	1260	3050	NN 4964K	4182964	52
  	440	118	3	359	-	1260	3050	NNU 4964	4482964	54.9
  	480	121	4	-	438	1350	2670	NN 3064	3282164	76.6
  	480	121	4	366	-	1350	2670	NNU 3064	3482164	76.9
  	480	160	4	367	-	1960	4300	NNU 4064	4482164	103
  	540	176	5	384	-	2090	3750	NNU 3164	3482764	154
  340	460	90	3	-	428	905	2020	NN 3968	3282968	42.9
  	460	118	3	-	428	1040	2450	NN 4968K	4182968	53.8
  	460	118	3	-	428	1350	3400	NN 4968	4282968	52.1
  	460	118	3	379	-	1350	3400	NNU 4968	4482968	57.8
  	520	133	5	-	473	1560	3020	NN 3068K	3182168	101
  	520	133	5	-	473	1560	3020	NN 3068	3282168	104
  	520	133	5	387	-	1560	3020	NNU3068	3482168	104
  	520	180	5	385	-	2420	5350	NNU 4068	4482168	141
  360	480	90	3	-	448	930	2130	NN 3972	3282972	44.9
  	480	118	3	399	-	1390	3550	NNU 4972	4482972	60.6
  	540	134	5	-	493	1630	3240	NN 3072	3282172	106
  	540	134	5	-	493	1630	3240	NN 3072K	3182172	106
  	540	134	5	413	-	1630	3240	NNU 3072	3482172	108
  	540	180	5	-	496	2530	5450	NN 4072	3282172	132
  	600	243	5	422	-	4000	8000	NNU4172	4482772	282
  380	520	140	4	-	485	1880	4600	NN 4976	4282976	81.3
  	520	140	4	426	-	1880	4600	NNU 4976	4482976	88.8
  	560	135	5	-	513	1590	3240	NN 3076K	3182176	110
  	560	135	5	-	513	1590	3240	NN 3076	3282176	114

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  380	620	194	5	-	559	2620	4950	NN 3176	3282776	224
  	620	194	5	449	-	2620	4950	NNU 3176	3482776	228
  400	500	100	2.1	430	-	905	2540	NNU 4880	4482880	45.7
  	540	106	4	-	504	1240	2400	NN 3980K	318980	71.3
  	600	148	5	-	549	1980	3660	NN 3080K	3182180	143
  	600	148	5	-	549	1980	3660	NN 3080	3282180	147
  	650	200	6	474	-	2770	5400	NNU 3180	3482780	262
  420	560	106	4	-	522	1280	2900	NN 3984	3282984	71.2
  	560	140	4	-	525	2000	5150	NN 4984	4282984	87.9
  	560	140	4	466	-	2000	5015	NNU 4984	4482184	97.2
  	620	150	5	-	568	2130	4450	NN 3084	3282184	154
  	620	150	5	478	-	2130	4450	NNU 3084	3482184	155
  	620	200	5	-	571	3150	7100	NN 4084	4282184	189
  	620	200	5	469	-	3400	7850	NNU 4084	4482184	209
  	700	224	6	501	-	3550	6800	NNU 3184	3482784	347
  440	540	100	2.1	470	-	950	2790	NNU 4888	4482888	49.5
  	650	157	6	-	596	2360	4900	NN 3088	3282188	177
  	650	157	6	500	-	2360	4900	NNU 3088	3482188	178
  	720	226	6	-	649	3500	6800	NN 3188	3282788	357
  460	580	118	3	497	-	1200	3600	NNU4892	4482892	76
  	620	118	4	-	578	1610	3700	NN 3992	3282992	94.5
  	620	160	4	510	-	2400	6200	NNU 4992	4482992	140
  	680	163	6	-	624	2470	5070	NN 3092K	3182192	204
  	680	163	6	-	624	2470	5070	NN 3092	3282192	204
  480	650	170	5	-	607	2690	7000	NN 4996	4282996	164
  	700	165	6	-	643	2600	5550	NN 3096	3282196	211

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  480	700	218	6	533	-	4300	8600	NNU4096	4482196	273
  	790	248	7.5	-	708	4050	8100	NN 3196	3282796	447
  500	670	170	5	554	-	2720	7200	NNU 49/500	44829/500	171
  	720	167	6	-	664	2580	5600	NN 30/500	32821/500	205
  	720	167	6	563	-	2580	5600	NNU 30/500	34821/500	220
  530	710	136	5	-	663	2040	4900	NN 39/530	32829/530	149
  	710	180	5	588	-	2900	7050	NNU 49/530	44829/530	202
  	780	185	6	-	715	3200	6900	NN 30/530	32821/530	296
  560	750	140	5	-	705	2370	4860	NN 39/560	32829/530	188
  	750	190	5	623	-	3250	8700	NNU 49/560	44829/560	239
  	780	180	8	-	725	2400	6400	NN 6/560	2872/560	266
  	820	195	8	-	756	2460	6560	NN 30/560K	31821/560	341
  	820	258	6	-	745	4100	10600	NN 40/560	42821/560	472
  	820	258	6	626	-	5720	13100	NNU40/560	44821/560	420
  	920	280	7.5	650	-	6850	13700	NNU 31/560	34827/560	738
  600	800	200	5	666	-	3850	10500	NNU 49/600	44829/600	284
  	800	200	5	-	755	3450	7180	NN 49/600K	41829/600	257
  	870	200	6	-	803	3420	7785	NN 30/600	32821/600	355
  	870	272	6	664	-	6138	14040	NNU 40/600	44821/600	530
  	980	375	7.5	699	-	8910	18990	NNU 41/600	44827/600	1100
  630	780	150	4	676	-	2290	7000	NNU 48/630	44828/630	160
  	850	218	6	-	793	4200	11400	NN 49/630	42829/630	328
  	850	218	6	704	-	4000	10800	NNU 49/630	44829/630	356
  	920	212	7.5	-	845	3860	8820	NN 30/630	32821/630	430
  	920	290	7.5	699	-	6885	15750	NNU 40/630	44821/630	635
  	1030	400	7.5	734	-	9900	21600	NNU 41/630	44827/630	1330
  670	900	230	6	-	838	4450	12330	NN 49/670	42829/670	419

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  670	900	230	6	738	-	4950	13100	NNU49/670	44829/670	430
  	980	230	7.5	-	901	4620	10260	NN 30/670K	31821/670	597
  	980	308	7.5	744	-	7578	17640	NNU 40/670	44821/670	765
  	1090	412	7.5	774	-	10890	22950	NNU 41/670	44827/670	1500
  710	870	160	4	759	-	2640	8350	NNU 48/710	44828/710	203
  	950	243	6	782	-	4850	13770	NNU49/710	44829/710	480
  	1030	236	7.5	-	951	5148	11880	NN 30/710	32821/710	590
  	1030	315	7.5	784	-	8415	19440	NNU 40/710	44821/710	850
  	1150	438	9.5	820	-	12060	25650	NNU 41/710	44827/710	1790
  750	920	170	5	-	879	3070	9180	NN 48/750	42828/750	240
  	1000	250	6	831	-	4950	14400	NNU 49/750	44829/750	540
  	1090	250	7.5	-	1007	6336	14400	NN 30/750	32821/750	705
  	1090	335	7.5	830	-	9180	21600	NNU 40/750	44821/750	925
  	1220	475	9.5	871	-	14490	31950	NNU 41/750	44827/750	2230
  800	1060	258	6	884	-	5247	15300	NNU 49/800	44829/800	615
  	1150	258	7.5	-	1065	7029	16200	NN 30/800	32821/800	790
  	1150	345	7.5	885	-	9720	23400	NNU 40/800	44821/800	1140
  	1280	475	9.5	921	-	14850	32850	NNU 41/800	44827/800	2390
  850	1030	180	5	905	-	3400	11400	NNU48/850	44828/850	310
  	1120	272	6	939	-	5346	16200	NNU 49/850	44829/850	715
  	1220	272	7.5	-	1130	7128	16740	NN 30/850	32821/850	940
  	1220	365	7.5	940	-	10530	25650	NNU 40/850	44821/850	1340
  	1360	500	6	976	-	19080	40500	NNU 41/850	44827/850	2900
  900	1180	280	6	986	-	5940	18000	NNU 49/900	44829/900	805
  	1280	280	7.5	-	1185	7425	18000	NN 30/900	32821/900	1050
  	1280	375	7.5	990	-	11520	28350	NNU 40/900	44821/900	1500
  	1420	515	6	1032	-	19800	42750	NNU 41/900	44827/900	3180

  Boundary dimensions						Basic load ratings		Designations		Mass
  mm						kN		Current	Original	kg
  d	D	B	rmin	Fw	Ew	Cr	Cor
  950	1250	300	7.5	1046	-	6633	20160	NNU 49/950	44829/950	960
  	1360	300	7.5	-	1255	8217	20160	NN 30/950	32821/950	1300
  	1360	412	7.5	1050	-	12780	31950	NNU 40/950	44821/950	1900
  950	1500	545	6	1092	-	22950	51300	NNU 41/950	44827/950	3830
  1000	1320	315	7.5	1103	-	7722	23400	NNU 49/1000	44829/1000	1250
  	1320	315	7.5	-	1238	8580	25200	NN49/1000	42829/1000	1200
  	1420	308	7.5	-	1316	9090	22050	NN 30/1000	32821/1000	1400
  	1420	412	7.5	1101	-	13860	34200	NNU 40/1000	44821/1000	2000
  	1580	580	6	1154	-	24750	55800	NNU 41/1000	44827/1000	4270
  1060	1400	335	7.5	1160	-	9450	27450	NNU 49/1060	44829/1060	1350
  	1500	325	9.5	-	1391	9900	24750	NN 30/1060	32821/1060	1650
  	1660	600	7.5	1214	-	27270	62550	NNU 41/1060	44827/1060	5070
  1120	1460	335	7.5	1220	-	9450	28350	NNU 49/1120	44829/1120	1450
  	1750	630	7.5	1279	-	30240	68850	NNU 41/1120	44827/1120	5600
  1180	1540	355	7.5	1285	-	10710	32400	NNU 49/1180	44829/1180	1650
  	1850	670	7.5	1350	-	33210	76500	NNU 41/1180	44827/1180	7200
  1250	1950	710	7.5	1426	-	37620	88200	NNU 41/1250	44827/1250	8000
  1320	1720	400	7.5	1440	-	12420	38250	NNU 49/1320	44829/1320	3100
  	1720	400	7.5	-	1620	13800	42500	NN49/1320	42829/1320	3060
  	2060	750	7.5	1507	-	41130	95400	NNU 41/1320	44827/1320	9400
  1400	2180	775	9.5	1598	-	44550	104400	NNU 41/1400	44827/1400	10700
  1500	2300	800	9.5	1709	-	47520	118800	NNU 41/1500	44827/1500	12300