EMQ DEEP
GROOVE BALL BEARINGS
 
 
Add: No.333 Xiahu Road, Taozhuang Town, Jiashan City, Zhejiang Province, China
 
Tel.: +86 573 8486 0885
Fax: +86 573 8486 0881
M.T.:139 6823 0098
 
E-mail: admin@aemeke.com
Http:// www.ottbearing.com
 
OTT Agency in Italy
AN.TEA srl
E-mail:acquisti@anteasrl.biz
TECHNICAL >>
# BEARING FITS
1.THE PURPOSE OF FITS
The Purpose of Fits is that let bearing inner ring or outer ring be both fixed firmly with shaft or housing,in case any circumferential slipping is occurred on the matching surface.
This kind of slipping which is called "creep"will cause many faults,such as :abnormal heating,the matching surface wear (abrasivee metallic particles ingress the interior of the bearing) and vibration etc.It may destory the bearing function.Therefore, it is important to let rings have tight ift in order that they are firmly fixed with shaft or housing.
2.THE DIMENSION TOLERANCE AND FIT OF SHAFT OR HOUSING
The metric dimension tolerance of shaft and housing bore is based on ISO 286,selecting the dimension tolerance from this standard to decide the fit situation between shaft,housing and bearing.
Regaring the dimension tolerance of shaft or housing bore & the fit relationship of bearing tolerance class P0,see the following FIg 1.
3.SELECTION OF FITS
It should fully be considered the bearing application conditionmwhen selects fits.
It should be considered the following items generally:
·Types and magnitude of load
·The distributing f operational temperature
·The internalclearance of bearing
·The processing quality of shaft and housing, material and housing thickness as well as structure
·Means of bearing mounting and dismounting
·Whether Or not use matching surface to avoid the heat expansion of shaft
·The type and dimension of bearing
The following are connectionwith above items to explain selection of fits.
1) THE INFLUENCE OF LOAD CONDITIONS
Basic on conditions, the bearing load can be divided into inner ring rotating load, outer ring rotating load and indeterminate direction load. The details can be found in Tab 2.
2)THE INFLUENCE OF LOAD MAGNITUDE
When inner ring is under the radial load, inner ring is slightly increased in the load direction. Therefore initial magnitude of interference will be decreased.
The loss of interference should be estimated using the following equations.
Therefore, when the radial load is heavy load (the value exceeds 2596 of CO), the fit must become tighter than light load.
If it impacts load,the fitting must tighter.
3)THE INFLUENCE OF MATCHING SURACE ROUGHNESS
If the plastic deformation of matching surace is considered, the effective inte rference will be influenced by the roughness of matching surface. It may use the following equations:
4)THE INFLUENCE OF TEMPERATURE
Generally speaking, the bearing operating temperature is higher than surrounding,moreover, when bearing rotating with load, the temperature of inner ring is higher than shaft, so the effective interference decreases due to heat expansion.
If the temperature difference between the bearingand housing is △T ,then the temperature difference between the matching surfaces of the shaft and inner ring is estimated to be about (0.1-0.15) △T.
The decrement in the interference of the inner ring due to this temperature difference △d may be calculated using Equation:
So, when the temperature of bearing is higher than shaft, the fit must tighter.
In addition, the interference may increase due to the temperature difference and the linear expansion coefficients all are different between outer ring and housing. Therefore, when considering avoiding heat expansion of shaft via sliding between outer ring and housing, we should pay more attention to this.
5) THE MAXIMUM STRESS OCCURRED BY FITTINGIN RINGS
The rings will be expanded and shrunken due to tight fit mounting so that will cause internal stress. Excessive stress may lead ring broken, should pay more attention to this. The maximum stress is ccurred by fitting in bearing rings may be calculated by the equations in Table3. For reference, it will be safe, when the maximum interference less than 1/1000 of shaft diameter,or the maximum stress less than 120MPa where getting from the equations in section 3.
6) OTHERS
We should improve the precision of shaft and housing due to higher accuracy requirement. Comparing with shaft, the housing normally is difficult to machining and poor precision, so it should Ioose the fitting of outer ring and housing. A tighter fitting is necessary due to adopting the thin housing and hollow shaft. The fitting should be loosed due to adopting the split housing. The fitting should tighter than usual when adopting the aluminum or light alloy housing. It is advisable to consult OTT.
# 4 RECOMMENDED FITS
As section1 described, many factors must be considered when selecting the proper fit, such as the characteristics and bearing load magnitudes, temperature differences, and methods of bearing mounting and dismounting. But in fact selecting the fiting, previous experience should be referred.
The fits for metric series bearings are used, as Tab4 showing. The recommended fits for some common applications are shown in Tab5-8.
# ACCURACY
Nominal Inside Diameter d (mm) Single Plane Averaged
I.D.Error dmp
Bs . Cs Nominal Outside Diameter D (mm) Dmp single Plane Averaged O.D.Error
Grade 0 Grade 6 Grade 5 Grade 4 Grade 0 and 6 Grade 5 and 4 Grade 0 Grade 6 Grade 5 Grade 4
Over Up-to Up Down Up Down Up Down Up Down Up Down Up Down Over Up-to Up Down Up Down Up Down Up Down
2.5 10 0 -8 0 -7 0 -5 0 -4 0 -120 0 -40 6 18 0 -8 0 -7 0 -5 0 -4
10 18 0 -8 0 -7 0 -5 0 -4 0 -120 0 -80 18 30 0 -9 0 -8 0 -7 0 -5
18 30 0 -10 0 -8 0 -6 0 -5 0 -120 0 -120 30 50 0 -11 0 -9 0 -7 0 -6
30 50 0 -12 0 -10 0 -8 0 -6 0 -120 0 -120 50 80 0 -13 0 -11 0 -9 0 -7
80 120 0 -15 0 13 0 -10 0 -8
# RADIAL GAP OF DEEP GROOVE BALL BEARING
Nominal Inside Diameter Group MC Group MC2 Group MC3 Group MC Group MC5 Group MC6
Over Up-to Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max.
- 9 0 5 3 8 5 10 8 13 13 20 20 28
Nominal Inside Diameter Group C2 Group CM (motor only) Standard Group CN Group C3 Group C4 Group C5
Over Up-to
10 0 7 3 10 2 13 8 23 14 29 20 37
10 18 0 9 4 11 3 18 11 25 18 33 25 45
18 24 0 10 5 12 5 20 13 28 20 36 28 48
24 30 1 11 5 12 5 20 13 28 23 41 30 53
30 40 1 11 9 17 6 20 15 33 28 46 40 64
40 50 1 11 9 17 6 23 18 36 30 51 45 73
# VIBRATION AND NOISE OF BEARING
Bearing
Inside
Diamster
Single Bearing Vibration (Acceleration)
Limit Value dB
Single Bearing Vibration (Speed)
Limit Value μm/s
Diameter
series O
Diameter
series 2
Diameter
series 3
V V1 V2 V3 V4
d(mm) Z Z1 Z2 Z3 Z Z1 Z2 Z3 Z4 Z Z1 Z2 Z3 Z4 L M H L M H L M H L M H L M H
5 37 36 34 30 38 37 34 32 - 39 37 35 33 - 110 72 60 74 48 40 58 36 30 35 21 18 32 11 11
6 37 36 34 30 38 37 34 32 - 39 37 35 33 - 110 72 60 74 48 40 58 36 30 35 21 18 32 1 1 11
7 39 38 35 31 40 38 36 34 - - - - - - 130 96 80 92 66 54 72 48 40 44 28 24 38 12 12
8 39 38 35 31 40 38 36 34 - - - - - - 130 96 80 92 66 54 72 48 40 44 28 24 38 12 12
9 41 40 36 32 42 40 37 35 - - - - - - 130 96 80 92 66 54 72 48 40 44 28 24 38 12 12
10 43 42 38 33 40 42 39 35 30 46 44 40 37 32 160 120 100 120 80 70 90 60 50 55 35 30 45 14 15
12 44 43 39 34 45 43 39 35 30 47 45 40 37 32 160 120 100 120 80 70 90 60 50 55 35 30 45 14 15
15 45 44 40 35 46 44 41 36 31 48 46 42 38 33 210 150 120 150 100 85 110 78 60 65 46 35 52 18 18
17 46 44 40 35 47 45 41 36 31 49 47 42 38 33 210 150 120 150 100 85 110 78 60 65 46 35 52 25 25
20 47 45 41 36 48 46 42 38 33 50 48 43 39 34 260 190 150 180 125 100 130 100 75 80 60 45 60 25 25
25 48 46 42 38 49 47 43 40 36 51 49 44 41 37 260 190 150 180 125 100 130 100 75 80 60 45 60 30 32
30 49 47 43 39 50 48 44 41 37 52 50 45 42 38 300 240 190 200 150 130 150 120 100 90 75 60 70 35 40
35 51 49 45 41 52 50 46 43 39 54 52 47 44 40 300 240 190 200 150 130 150 120 100 90 75 60 70 42 45
40 53 51 46 42 54 52 47 44 40 56 54 49 45 41 360 300 260 240 180 160 180 150 130 110 90 80 82 50 50
45 55 53 48 45 56 54 49 46 43 58 56 51 47 44 360 300 260 240 180 160 180 150 130 110 90 80 82 60 60
50 57 54 50 47 58 55 51 48 45 60 57 53 49 46 420 320 320 280 200 200 210 160 160 125 100 100 95 70 70
# SEALING STRUCTURE OF DEEP GROOVE BEARING
Comparison of Our Dust-proof and Sealing Bearing Performance (Reference Only)
Structure Cage Type (ZZ) Non-contact Rubber Sealing Ring (RZ)  Contact Rubber Sealing (RS)
Friction Torque Small Small Because of contact sealing, Models RS1 and RS2 are bigger than Models ZZ and RZ and Model RS3 is the biggest.
High Speed Performance Good Good Because the limit of contact sealing. (RS 3 has a high temperature rise)
Grease Sealing Good Better than Model RZ A little better than Model RZ but Model RS1 is better than Model RS2 and Model RS3 is better than Model RS1.
Dust-proof Good Better than Model ZZ (could be used in some dust environment) The Best {could be used in most dust condition) but Model RS2 is superior to Model RS1 and Model RS3 is superior to Model RS2.
Water Resistance Unsuitable  Unsuitable Good (could be used in splash condition)
Range of Application Temperature  -10~+110℃  -10~+110℃  -10~+110℃ 

Note: The description is for standard products only. However, the range of application temperature could be extended if you select cold resistant or hot resistant grease and rubber. Please contact Aemeke if you have any special requirement.
# GREASE TABLE
Manufacturer Brand Viscosity Base oil Drop
Point ℃
Consitency Temperature
range ℃
NMB
Esso Beacon 325 Lithium Diester 193 290 -60 -+120 LG20
  AC 205 Nathium Mineral     -25- -+120  
  Andok B Nathium Mineral 260 280 -40- -+120 LG38
  Andok C Nathium Mineral >260 205 -20- -+120 LG39
  Andok 260 Nathium Mineral 200 250 -30- -+150 LG71
  Andok RB300 Lithium Calcium Mineral 175 300 -30- -+100  
KYODO NS Hilube Lithium Diester 190 255 -40- -+130 LY72
YUSHI Multemp PS2 Lithium Diester 189 280 -50- - +110 LY121
  Multemp SRL Lithium Ester 191 245 -40- -+150  
  Multemp SC-A Urea   >260 280 0~ +160  
  Multemp ET150 Urea Mineral >260 280 -10- -+160  
  Oneluba Lithium Diester Mineral 198 370 -10- - +110  
  Adrex Lithium Mineral 198 300 -10- -+120  
  Parmax   Mineral 180 300 -10- -+120  
  Emalibe 1130 Urea Mineral >260 300 -10- -+130  
  Unilube DL1 Lithium Mineral 185 332 -10- - +110  
  Alumix HD1   Mineral 247 335 0~ +120  
Kluber Staburage NBU12 Barium Mineral 220 270 -35- -+150  
  lsoflexNBU15 Barium Diester Mineral 220 280 -60- +130  
  AsonicGLY32 Lithium Sythetic     -50- +140  
  AsonicGHY72 Polyhamstoff Ester Mineral     -40- +180  
  Is of lex super LDS18 Lithium Diester 190 280 -60- +130  
  Is of lex super TEL Lithium Ester Mineral     -65 -+70 LY218
  lsoflexLDS18 SpezialA Lithium Diester 190 280 -60- +130  
  lsoflexPDB38CX100 Lithium Ester     -70- +120  
  Is of lex Top as NB52 Barium Sythetic hydrocarbon 240 280 -60- +170  
  Barrierta L55/2 Fluorotelomer Fluorinated   280 -35- +260  
  Barrierta EL Fluorotelomer Fluorinated   280 -50- +180  
  Barrierta IMI/V Fluorotelomer Fluorinated     -50- +220  
  UnisilikonTK44N2 Na-komplex Silicone   280 -60- +230  
Dow Corning Molykote 33M Lithium Silicone 210   -70- +180 LY81
  Molykote 44M Lithium Silicone 204   -40- +200 LY13
  Molykote 55M Lithium Silicone   260 -55- +165 LY52
  Molykote BR2 plus Lithium Mineral   260 -30- +150  
  Molykote FS1292 Fluorotelomer Phlorosicone >232   -40- +200 LY59
  Molvkote FS3451 Fluorotelomer Phlorosicone >260 280 -40- +230  
Shell Alvania No.2 Lithium Mineral 182 310 -25- +120 LY83
  Alvania No.3 Lithium Mineral 183 285 -20- +135 LY84
  Alvania RA Lithium Mineral 183 272 -25- +120 LY18
  Alvania EP2 Lithium Mineral 185 233 -10- +100  
  Sunlight 2 Lithium Mineral 196 252 -20- +120  
  Dolium R   Mineral 238 276 -20- +140 LY119
  Aero shell NO.5 Microgel Mineral >260 273 -10- +130 LG35
  Aero shell NO.7 Microgel Diester >260 281 -70- +150 LG49
  Aero shell N0.15A Fluorotelomer Silicone >260 282 -70- +260  
Mobil Oil Mobilux2 Lithium Mineral 190 288 -20- +120  
  Mobigrease 22 Lithium Diester Mineral 192 280 -50- +140  
  Mobigrease 28 Bentonite Sy nthetichyd rocarb on >260 280 -60- +180 LY48
  Mobibex 47   Mineral >260 274 -20- +120  
Du Pont Krytox 240AC Fluorotelomer Fluorinated   280 -35- +280 LY101
  Krytox 283AC Fluorotelomer Fluorinated   280 -35- +280  
  Krvtox 143AC Fluorotelomer Fluorinated   282 -35- +280 LY115
Toray ilicone SH44M Lithium Silicone 210 229 -40- +180  
  SH33L Lithium Silicone 210   -70- +140  
  SH41 Lithium Silicone   260 -10- +200  
Caltex Chevron SRI-2 Urea Mineral   300 -30- + 175 LY75
General leotrio Anderol SRI-2 Lithium Diester   280 -60- +150  
  Versilube G-300 Lithium Silicone   293 -70- +230 LY15
  Versilube F-50   Silicone     -70- +230 LY5