Materials and Engineering Specs for Bearings

BEARING EXPERTS

Always Trust the Experts for your Bearing needs!

Materials and Engineering Specs for Bearings

RINGS & BALLS-Bearing Experts Bearing uses homemade or imported vacuum degrassed, high-carbon,
chromium bearing steel as its standard material for precision bearing rings and balls. Table 1 below shows
the chemical composition.

Table 1 HIGH CARBON CHROMIUM BEARING STEEL £¨units:%£©
Spec.No	Symbol	C	S1	Mn	P	S	Cr	Ni	Mo
CHINA YJZ-84	GCr15	0.95-1.05	0.15-0.35	0.20-0.40	¡Ü0.027	¡Ü0.02	1.03-1.65	¡Ü0.025	-
KOREA KS D 3525	STB 2	0.95-1.10	0.15-0.35	¡Ü0.50	¡Ü0.025	¡Ü0.025	1.30-1.60	¡Ü0.25	¡Ü0.08
	STB 3	0.95-1.10	0.40-0.70	0.9-1.15	¡Ü0.025	¡Ü0.025	0.90-1.20	¡Ü0.25	¡Ü0.08
	STB 4	0.95-1.10	0.15-0.35	¡Ü0.50	¡Ü0.025	¡Ü0.025	1.30-1.60	¡Ü0.25	0.10-0.25
JAPAN JIS G 4805	SUJ 1	0.95-1.10	0.15-0.35	¡Ü0.50	¡Ü0.025	¡Ü0.025	0.90-1.20	¡Ü0.25	¡Ü0.08
	SUJ 2	0.95-1.10	0.15-0.35	¡Ü0.50	¡Ü0.025	¡Ü0.025	1.30-1.60	¡Ü0.25	¡Ü0.08
	SUJ 3	0.95-1.10	0.40-0.70	0.90-1.15	¡Ü0.025	¡Ü0.025	0.90-1.20	¡Ü0.25	¡Ü0.08
	SUJ 4	0.95-1.10	0.15-0.35	¡Ü0.50	¡Ü0.025	¡Ü0.025	1.30-1.60	¡Ü0.25	0.10-0.25
	SUJ 5	0.95-1.10	0.40-0.70	0.90-1.15	¡Ü0.025	¡Ü0.025	0.90-1.20	¡Ü0.25	0.10-0.25
U.S.A.AISI SAE J405	E 51100	0.98-1.10	0.20-0.35	0.25-0.45	¡Ü0.025	¡Ü0.025	0.90-1.15	¡Ü0.25	¡Ü0.08
U.S.A.AISI SAE J405	E 52100	0.98-1.10	0.20-035	0.25-0.45	¡Ü0.025	¡Ü0.025	1.30-1.60	¡Ü0.25	¡Ü0.08
Germany VDEH(German lron & Steel Associatiobn)	105 Cr 2	1.00-1.10	0.15-0.35	0.25-0.40	¡Ü0.030	¡Ü0.025	0.40-0.60	-	-
	105 Cr 4	1.00-1.10	0.15-0.35	0.25-0.40	¡Ü0.030	¡Ü0.025	0.90-1.15	-	-
	105 Cr 6	0.90-1.05	0.15-0.35	0.25-0.40	¡Ü0.025	¡Ü0.020	1.40-1.65	-	-
	100 CrMn 6	0.90-1.05	0.50-0.70	1.00-1.20	¡Ü0.025	¡Ü0.020	1.40-1.65	-	-

RETAINERS-Our standard bearing retainers are made from quality cold rolled carbon steel. Nylon or brass are available upon request.

SEALS & SHIELDS-Our shields also employ quality carbon steel as standard. We uses a variety of high temperature operation and compatibility with grease. Buna-Nitrile is the standard material used.

LUBRICANTS-Our common greases used and their features shown in Table 2.

Table 2 GREASE

MFGER	BRAND	THICKER	BASE OIL	DROPPING POINT	¡¡	TEMP.	Our CODE
ESSO	Beacom325	Lithium	Diester	193	290	¡¡	L06
	AC205	Natrium	Mineral	¡¡	¡¡	-60~+120	¡¡
	Andok B.	Natrium	Mineral	260	280	-25~+120	L01
	Andok C	Natrium	Mineral	¡Ý260	205	-40~+120	L02
	Andok 260	Natrium	Mineral	200	250	-20~+150	L07
Kyodo Yushi
	Multemp PS2	Lithium	Diester	189	280	-50~+110	L20
	Multemp SRL	Lithium	Ester	191	245	-40~++150	L21
	Multemp SC-A	Urea	¡¡	260	280	0~+160	¡¡
	Multemp ETISO	Urea	Mineral	260	280	-10~+160	¡¡
KLüber	Staburags NBU12	Barium	Mineral	220	270	-35~+150	¡¡
¡¡	Isoflex NBU15	Barium	Diester Mineral	220	280	-60~+130	¡¡
¡¡	Asonic Gly32	Lithium	Sythetic	¡¡	¡¡	-50~+140	¡¡
¡¡	Asonic GHY72	Polyhamstoff	Ester	¡¡	¡¡	-40~+180	¡¡
¡¡	Unisilikon TK44N2	Na-Komplex	Silicone	¡¡	¡¡	-60~+230	¡¡

Dow Corning	Molykote 33M	Lithium	Silicone	210	260	-70~+180	¡¡
	Molykote 44M	Lithium	Silicone	204	260	-40~+200	¡¡
	Molykote 55M	Lithium	Silicone	¡¡	¡¡	-55~+165	¡¡
	Molykote FS3451	Fluorotelomer	Phlorosilicone	¡Ý260	285	-40~+230	¡¡
Shell	Alvania No.2	Lithium	Mineral	182	272	-25~+120	L15
	Alvania No.3	Lithium	Mineral	183	233	-20~+135	L16
	Alvania RS	Lithium	Mineral	183	252	-25~++120	¡¡
	Dolium R	¡¡	Mineral	238	281	-20~+140	¡¡
	Aero shell No.5	Microgel	Mineral	¡Ý260	282	-10~+130	L40
	Aero shell No.7	Microgel	Diester	¡Ý260	288	-70~+150	L42
	Aero shell No.15A	Flaorotelomer	Silicone	¡Ý260	280	-70~+260	¡¡
Mobil Oil	Mobilux 2	Lithium	Mineral	190	280	-20~+130	¡¡
	Mobilgrease 22	Lithium	Diester Mineral	192	274	-50~+140	L09
	Mobilgrease 28	Bentonite	Sythetic hydrocarbon	¡Ý260	280	-60~+180	¡¡
	Mobilplex 47	¡¡	Mineral	¡Ý260	280	-20~+120	¡¡
Du Pont	Krytox 240AC	Fluorotelomer	Fluorinated	¡¡	282	-35~+290	¡¡
	Krytox 283AC	Fluorotelomer	Fluorinated	¡¡	229	-35~+290	¡¡
	Krytox 143AC	Fluorotelomer	Fluorinated	¡¡	¡¡	-35~+290	¡¡
Caltex	Chevron SRI-2	Urea	Mineral	¡¡	293	-30~+175	L19
Caltex	Anderol L-793A	Lithium	Diester	¡¡	¡¡	-60~+150	¡¡

II. TOLERANCE

Bearing tolerance includes dimensional tolerance and revolving tolerance. Dimensional tolerance is a request when bearings are mounted on shafts or in housings. It includes bore/outerside diameter deviation from basic, inner ring/outer ring width deviation from basic and radius allowance . Geometric tolerance includes bore/outside diameter deviation in single plane, inner ring/outer ring width deviation in single radial plane. Revolving tolerance includes radial and axial runout of assembled bearing inner ring and outer ring, inner ring reference face runout with bore and outside cylindrical surface runout with outer ring reference face.

Tolerance class ranges from common class 0 to 6,5,4 and 2,from low to high. Table 3 below is the tolerance class stipulated in Chinese GB307 standard and its comparison with some other standards.

Table 3 COMPARISON OF TOLERANCE CLASS
Nationality	Standard Number	Preision grade
Chinese	GB307	0(G)	6E	5(D)	4(C)	2(B)
ISO	ISO492	0	6	5	4	2
Sweden	Version 1985	0	P6	P5	P4	P2
West Germany	DIN 620/2	Po	P6	P5	P4	P2
U.S.A	ANSI B3.14	ABEC1	ABEC3	ABEC5	ABEC7	ABEC9
Japan	JIS B1514	0	6	5	4	2

The standard manufacturing tolerance for our precision radial bearings is class 6, as shown in Table 4.

Table 4 INNER RING
d mm		¡÷ dmp		Vdp			Vdmp	Kia	¡÷ BS		VBS
				Diameter series					all	normal
				9	0.1	2.3.4			all	normal
Over	Incl.	High	Low	Max			Max	Max	High	Low	Max
2.5	10	0	-7	9	7	5	5	6	0	-120	15
10	18	0	-7	9	7	5	5	7	0	-120	20
18	30	0	-8	10)	8	6	6	8	0	-120	20)
30	50	0	-10	13	10	8	8	10	0	-120	20
50	80	0	-12	15	15	9	9	10	0	-150	25

OUTER RING
D mm		¡÷ Dmp		VDP				VDmp	Kea	¡÷ Cs		Vcs
				open bearings		capped
				Diameter series
				9	0.1	2.34	0.1.2.3.4
Over	Incl.	High	Low	Max				Max	Max	High	Low	Max
6	18	0	-7	9	7	5	9	5	8	Identical to ¡÷ Bs and VBs of onne ring of same bearing
18	30	0	-8	10	8	6	10	6	9
30	50	0	-9	11	9	7	13	7	10
50	80	0	-11	14	11	8	16	8	13

Where:

Basic bore diameter

Basic outside diameter

¡÷ dmp

Single plane mean bore diameter deviation from basic

¡÷ Dmp

Single plane mean outer diameter deviation from basic

Vdp

Bore diameter variation in a single radial plane

VDp

Outside diameter variation in a single radial plane

Vdmp

Mean vore diameter variation

VDmp

Mean outside diameter variation

Kia

Radial runout of assembled bearing inne ring

Kea

Radial runout of assembled bearing outer ring

¡÷ Bs

Single inner ring width deviation from basic

¡÷ Cs

Single outer ring width deviation from basic

VBs

Inner ring width variation

VCs

Outer ring width variation

III¡¢CLEARANCE

Bearing clearance means the value of displacement of the unfixed ring when it moves against the fixed ring in radial or axial direction before the bearing is mounted on a shaft or in a housing. According to the movement direction, it falls into radial clearance and axial clearance.

The standard clearance for our deep groove ball bearings are divided into four groups:C2, C0, C3&C4 as shown below in Table 5:

Table 5 RADIAL CLEARANCE
mm(d)		C2		C0		C3		C4
over	incl	Min	Max	Min	Max	Min	Max	Min	Max
6	10	0	7	2	13	8	23	14	29
10	18	0	9	3	18	11	25	18	33
18	24	0	10	5	20	13	28	20	36
24	30	1	11	5	20	13	23	20	41
30	40	1	11	6	20	15	33	28	46
40	50	1	11	6	23	18	36	30	51

IV¡¢VIBRATION

Bearing vibration means bearing components' elastic deformation that varies with time and all other movement that deviates from a theoretic position except that necessary to bearing functions. It has two modes-acceleration(dB) and velocity(¦Ìm/s)¡¢Vibration acceleration is examined according to Z, Z1, Z2 and Z3 values. Grade Z is fundamental, Z1, Z2 &Z3 successively indicate the vibration level ranges from low to high. For detailed requirements, see Table6. Similary, vibration velocity is examined as per V, V1, V2 & V3. Grade V is fundamental, V1, V2 & V3 successively indicate the vibration level ranges from low to high. For details, see Table 7. Generally, velocity examination is better than acceleration examination in that it can more reflect bearings' manufacturing level and bearings/ inherent quality.

While our company keeps control of vibration velocity values, we also carry out vigorous control on abnormal noise from running bearings in test according to requirements of electric motor quality bearings.

Table 6 VIBRTION (ACCELERATION)LIMITES FOR SINGLE BEARING dB
mm(d)	Diameter Series£¨1£©			Diameter Series£¨2£©			Diameter Series£¨3£©
mm(d)	Z	Z1	Z2	Z1	Z2	Z3	Z1	Z2	Z3
5	37	36	34	37	34	32	37	35	33
6	37	36	34	37	34	32	37	35	33
7	39	38	35	38	36	34	---	---	---
8	39	38	35	38	36	34	---	---	---
9	41	40	36	40	37	35	---	---	---
10	43	42	38	42	39	35	44	40	37
12	44	43	39	43	39	35	45	40	37
15	45	44	40	44	41	36	46	42	38
17	46	44	40	45	41	36	47	42	38
20	47	45	41	46	42	38	48	43	39
25	48	46	42	47	43	40	49	44	41
30	49	47	43	48	44	41	50	45	42
35	51	49	45	50	46	43	52	47	44
40	53	51	46	52	47	44	54	49	45
45	55	53	48	54	49	46	56	51	47
50	57	54	50	55	51	48	57	53	49

Table 7 VIBRATION (VELOCITY) LIMITES FOR SINGLE BEARIN u m/s
mm(d)	V			V1			V2			V3
mm(d)	low band	mid band	high band	low band	mid band	high band	low band	mid band	high band	low band	mid band	high band
5	110	72	60	90	60	50	58	36	30	35	21	18
6	110	72	60	90	60	50	58	36	30	35	21	18
7	130	96	80	110	80	65	72	48	40	44	28	24
8	130	96	80	110	80	65	72	48	40	44	28	24
9	130	96	80	110	80	65	72	48	40	44	28	24
10	160	120	100	140	100	85	90	60	50	55	35	30
12	160	120	100	140	100	85	90	60	50	55	35	30
15	210	150	120	180	130	100	110	78	60	65	46	35
17	210	150	120	180	130	100	110	78	60	65	46	35
20	260	190	150	220	160	125	130	100	75	80	60	45
22	260	190	150	220	160	125	130	100	75	80	60	45
25	260	190	150	220	160	125	130	100	75	80	60	45
28	260	190	150	220	160	125	130	100	75	80	60	45
30	300	240	190	250	200	160	150	120	100	90	75	60
32	300	240	190	250	200	160