Product Details
R188ZZ Double Metal Shielded Ball Bearing Chrome Steel P0 Z2 Bearing for Industrial Machine,Power Tools and Mechanical Equipment
- 【Package & Size】R188ZZ rolling bearing. I.D.=1/4inch,O.D.=1/2inch,Thickness=3/16inch
- 【Seal】R188ZZ bearings are metal Shielded on both side to keep lubricant in and prevent the intrusion of liquid impurities.High temperature resistance
- 【Material】Chrome Steel(GCr15), corrosion resistance,durability and resistance to under heavy loads,Static load rating of 80 newtons and dynamic load rating of 207 newtons
- 【Features】Low noise Z2, ABEC Tolerance 1 (P0), High speed. High temperature resistance. Resistance to high load. Suitable for kinds of applications.
- 【Wide application】 Widely used in industrial machine, motorcycle, automobile, power tools and mechanical equipment and other kinds of field.


R Series Deep Groove Ball Bearings can be customed sizes, below specification chart is for your reference.
Technical Parameters of R Series Deep Groove Ball Bearing:
Basic Bearing No. | Bore d | Outer DiameterD | Width W | Radius r | Basic Load Rating KN |
Open | Shield Seal | Dynamic C | Static C0 |
mm | inch | mm | inch | mm | inch | mm | inch | mm | inch |
R156 | 4.763 | 0.1875 | 7.938 | 0.3125 | 2.78 | 0.1094 | 3.18 | 0.1250 | 0.1 | 0.004 | 0.395 | 0.143 |
R166 | 4.763 | 0.1875 | 9.525 | 0.3750 | 3.18 | 0.1250 | 3.18 | 0.1250 | 0.1 | 0.004 | 0.71 | 0.268 |
R3 | 4.763 | 0.1875 | 12.700 | 0.5000 | 3.97 | 0.1562 | 4.98 | 0.1960 | 0.15 | 0.006 | 1.31 | 0.49 |
R3A | 4.763 | 0.1875 | 12.700 | 0.5000 | 4.98 | 0.1960 | 4.98 | 0.1960 | 0.15 | 0.006 | 1.31 | 0.49 |
R168 | 6.350 | 0.2500 | 9.525 | 0.3750 | 3.18 | 0.1250 | 3.18 | 0.1250 | 0.1 | 0.004 | 0.268 | 0.136 |
R188 | 6.350 | 0.2500 | 12.700 | 0.5000 | 3.18 | 0.1250 | 4.76 | 0.1875 | 0.15 | 0.006 | 0.83 | 0.37 |
R4 | 6.350 | 0.2500 | 15.875 | 0.6250 | 4.98 | 0.1960 | 4.98 | 0.1960 | 0.2 | 0.008 | 1.48 | 0.615 |
R4A | 6.350 | 0.2500 | 19.050 | 0.7500 | 5.56 | 0.2188 | 7.14 | 0.2812 | 0.3 | 0.012 | 2.34 | 0.885 |
R6 | 9.525 | 0.3750 | 22.225 | 0.8750 | 5.56 | 0.2188 | 7.14 | 0.2812 | 0.3 | 0.012 | 3.3 | 1.4 |
R8 | 12.70 | 0.5000 | 28.575 | 1.1250 | 6.35 | 0.2500 | 7.94 | 0.3125 | 0.3 | 0.012 | 3.912 | 2.245 |
R8-7 | 11.113 | 0.4375 | 28.575 | 1.1250 | 6.35 | 0.2500 | … | … | 0.3 | 0.012 | 3.912 | 2.245 |
R10 | 15.875 | 0.6250 | 34.925 | 1.3750 | 7.14 | 0.2812 | 8.73 | 0.3438 | 0.6 | 0.024 | 4.605 | 2.774 |
R12 | 19.050 | 0.7500 | 41.275 | 1.6250 | 7.94 | 0.3125 | 11.11 | 0.4375 | 0.6 | 0.024 | 7.246 | 4.445 |
R188ZZ Bearing Display


Wide Applications of Deep Groove Ball Bearings:

Customization Welcomed:
-
We can printing your brand (logo,artwork)on the shield or laser engraving your brand on the shield.
-
We can custom your packaging according to your design.
-
All copyright owned by clients and we promised don't disclose any information.
Packing and Shipping:
-
The deep groove ball bearings will be securely packaged individually, or tube packing or packed as customization packing
-
Shipping method is negotiable.

ABEC-1 Tolerance Class ABEC-1 (P0)
Inner Ring | Tolerance in um/s |
d mm | Δdmp | 9 | Vdp²)0,1 Diameter Series | 2,3,4 | Vdmp | Kia | ΔBs | Vbs |
over | including | high | low | max | max | max | high | low | max |
1)0.6 | 2.5 | 0 | -8 | 10 | 8 | 6 | 6 | 10 | 0 | -40 | 12 |
2.5 | 10 | 0 | -8 | 10 | 8 | 6 | 6 | 10 | 0 | -120 | 15 |
10 | 18 | 0 | -8 | 10 | 8 | 6 | 6 | 10 | 0 | -120 | 20 |
18 | 30 | 0 | -10 | 13 | 10 | 8 | 8 | 13 | 0 | -120 | 20 |
30 | 50 | 0 | -12 | 15 | 12 | 9 | 9 | 15 | 0 | -120 | 20 |
50 | 80 | 0 | -15 | 19 | 19 | 11 | 11 | 20 | 0 | -150 | 25 |
Outer Ring | Tolerance in um/s |
D mm | Δdmp | VDp2)4)Open Bearings Diameter Series | Capped Bearings2)3) | Vdmp | Kia | ΔBs | Vbs |
9 | 0,1 | 2,3,4 | 2,3,4 |
over | including | high | low | max | max | max | high | low | max |
1)2.5 | 6 | 0 | -8 | 10 | 8 | 6 | 10 | 6 | 15 | Identical to ΔBs and VBs of inner ring of same bearing |
6 | 18 | 0 | -8 | 10 | 8 | 6 | 10 | 6 | 15 |
18 | 30 | 0 | -9 | 12 | 9 | 7 | 12 | 7 | 15 |
30 | 50 | 0 | -11 | 14 | 11 | 8 | 16 | 8 | 20 |
50 | 80 | 0 | -13 | 16 | 13 | 10 | 20 | 10 | 25 |
80 | 120 | 0 | -15 | 19 | 19 | 11 | 26 | 11 | 35 |
120 | 150 | 0 | -18 | 23 | 23 | 14 | 30 | 14 | 40 |
ABEC-3 Tolerance Class ABEC-3 (P6)
Inner Ring | Tolerance in um/s |
d mm | Δdmp | 9 | Vdp²)0,1 Diameter Series | 2,3,4 | Vdmp | Kia | ΔBs | Vbs |
over | including | high | low | max | max | max | high | low | max |
11)0.6 | 2.5 | 0 | -7 | 9 | 7 | 5 | 5 | 5 | 0 | -40 | 12 |
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 | Tolerance in um/s |
D mm | Δdmp | VDp2)4)Open Bearings Diameter Series | Capped Bearings2)3) | Vdmp | Kia | ΔBs | Vbs |
9 | 0,1 | 2,3,4 | 2,3,4 |
over | including | high | low | max | max | max | high | low | max |
1)2.5 | 6 | 0 | -7 | 9 | 7 | 5 | 9 | 5 | 8 | Identical to ΔBs and VBs of inner ring of same bearing |
6 | 18 | 0 | -7 | 9 | 7 | 5 | 9 | 5 | 8 |
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 |
80 | 120 | 0 | -13 | 16 | 16 | 10 | 20 | 10 | 18 |
120 | 150 | 0 | -15 | 19 | 19 | 11 | 25 | 11 | 20 |
ABEC-5 Tolerance Class ABEC-5 (P5)
Inner Ring | Tolerance in um/s |
d mm | Δdmp | Vdp²)Diameter Series | Vdmp | Kia | Sd | Sis3) | ΔBs | Vbs |
9 | 0,1,2,3,4 |
over | including | high | low | max | 3 | max | max | max | High | Low | max |
1)0.6 | 2.5 | 0 | -5 | 5 | 4 | 3 | 4 | 7 | 7 | 0 | -40 | 5 |
2.5 | 10 | 0 | -5 | 5 | 4 | 3 | 4 | 7 | 7 | 0 | -40 | 5 |
10 | 18 | 0 | -5 | 5 | 4 | 3 | 4 | 7 | 7 | 0 | -80 | 5 |
18 | 30 | 0 | -6 | 6 | 5 | 3 | 4 | 8 | 8 | 0 | -120 | 5 |
30 | 50 | 0 | -8 | 8 | 6 | 4 | 5 | 8 | 8 | 0 | -120 | 5 |
50 | 80 | 0 | -9 | 9 | 7 | 5 | 5 | 8 | 8 | 0 | -150 | 6 |
Outer Ring | Tolerance in um/s |
D mm | Δdmp | Vdp²)Diameter Series | Vdmp | Kia | SD4) SD15) | Sea4)5) | ΔBs | Vbs |
9 | 0,1,2,3,4 |
over | including | high | low | max | | max | max | max | High | Low | max |
1)2.5 | 6 | 0 | -5 | 5 | 4 | 3 | 5 | 8 | 8 | | 5 |
6 | 18 | 0 | -5 | 5 | 4 | 3 | 5 | 8 | 8 | 5 |
18 | 30 | 0 | -6 | 6 | 5 | 3 | 6 | 8 | 8 | 5 |
30 | 50 | 0 | -7 | 7 | 5 | 4 | 7 | 8 | 8 | 5 |
50 | 80 | 0 | -9 | 9 | 7 | 5 | 8 | 8 | 10 | 6 |
80 | 120 | 0 | -10 | 10 | 8 | 5 | 10 | 9 | 11 | 8 |
120 | 150 | 0 | -11 | 11 | 8 | 6 | 11 | 10 | 13 | 8 |
ABEC-7 Tolerance Class ABEC-7 (P4)
Inner Ring | Tolerance in um/s |
d mm | Δdmp | Δds | Vdp²)Diameter Series | Vdmp | Kia | Sd | Sia | ΔBs | Vbs |
7,8,9 | 1,7,2,3,4 |
over | including | high | low | high | low | max | max | max | max | max | High | low | Low | max |
1)0.6 | 2.5 | 0 | -4 | 0 | -4 | 4 | 3 | 2 | 2.5 | 3 | 3 | 0 | -40 | -40 | 2.5 |
2.5 | 10 | 0 | -4 | 0 | -4 | 4 | 3 | 2 | 2.5 | 3 | 3 | 0 | -40 | -40 | 2.5 |
10 | 18 | 0 | -4 | 0 | -4 | 4 | 3 | 2 | 2.5 | 3 | 3 | 0 | -80 | -80 | 2.5 |
18 | 30 | 0 | -5 | 0 | -5 | 5 | 4 | 2.5 | 3 | 4 | 4 | 0 | -120 | -120 | 2.5 |
30 | 50 | 0 | -6 | 0 | -5 | 6 | 4 | 3 | 4 | 4 | 4 | 0 | -120 | -120 | 3 |
50 | 80 | 0 | -7 | 0 | -5 | 7 | 5 | 3.5 | 4 | 5 | 5 | 0 | -150 | -150 | 4 |
Outer Ring | Tolerance in um/s |
D mm | Δdmp | Δds | Vdp²)Diameter Series | Vdmp | Kia | Sd | Sia | ΔBs | Vbs |
7,8,9 | 1,7,2,3,4 |
over | including | high | low | high | low | max | max | max | max | max | High | low | max |
1)2.5 | 6 | 0 | -4 | 0 | -4 | 4 | 3 | 2 | 3 | 4 | 5 | Identical to ΔBs and VBs of inner ring of same bearing | 2.5 |
6 | 18 | 0 | -4 | 0 | -4 | 4 | 3 | 2 | 3 | 4 | 5 | 2.5 |
18 | 30 | 0 | -5 | 0 | -5 | 5 | 4 | 2.5 | 4 | 4 | 5 | 2.5 |
30 | 50 | 0 | -6 | 0 | -6 | 6 | 5 | 3 | 5 | 4 | 5 | 2.5 |
50 | 80 | 0 | -7 | 0 | -7 | 7 | 5 | 3.5 | 5 | 4 | 5 | 3 |
80 | 120 | 0 | -8 | 0 | -8 | 8 | 6 | 4 | 6 | 5 | 6 | 4 |
120 | 150 | 0 | -9 | 0 | -9 | 9 | 7 | 5 | 7 | 5 | 7 | 5 |

Tolerance Data For Sibration of Single Bearing
D | V | V1 | V2 | V3 | V4 |
mm | Low | Medium | High | Low | Medium | High | Low | Medium | High | Low | Medium | High | Low | Medium | High |
3,4 | 80 | 44 | 44 | 60 | 35 | 32 | 48 | 26 | 22 | 31 | 16 | 15 | 28 | 10 | 10 |
5,6 | 110 | 72 | 60 | 74 | 48 | 40 | 58 | 36 | 30 | 35 | 21 | 18 | 32 | 11 | 11 |
7,8,9 | 130 | 96 | 80 | 92 | 66 | 54 | 72 | 48 | 40 | 44 | 28 | 24 | 38 | 12 | 12 |
10,12 | 160 | 120 | 100 | 120 | 80 | 70 | 90 | 60 | 50 | 55 | 35 | 30 | 45 | 14 | 15 |
15 | 210 | 150 | 120 | 150 | 100 | 85 | 110 | 78 | 60 | 65 | 46 | 35 | 52 | 18 | 18 |
17 | 210 | 150 | 120 | 150 | 100 | 85 | 110 | 78 | 60 | 65 | 46 | 35 | 52 | 25 | 25 |
20 | 260 | 190 | 150 | 180 | 125 | 100 | 130 | 100 | 75 | 80 | 60 | 45 | 60 | 25 | 25 |
22,25 | 260 | 190 | 150 | 180 | 125 | 100 | 130 | 100 | 75 | 80 | 60 | 45 | 60 | 30 | 32 |
28 | 260 | 190 | 150 | 180 | 125 | 100 | 130 | 100 | 75 | 80 | 60 | 45 | 60 | 35 | 40 |
30,32 | 300 | 240 | 190 | 200 | 150 | 130 | 150 | 120 | 100 | 90 | 75 | 60 | 70 | 35 | 40 |
35 | 300 | 240 | 190 | 200 | 150 | 130 | 150 | 120 | 100 | 90 | 75 | 60 | 70 | 42 | 45 |
40 | 360 | 300 | 260 | 240 | 180 | 160 | 180 | 150 | 130 | 110 | 90 | 80 | 82 | 50 | 50 |
45 | 360 | 300 | 260 | 240 | 180 | 160 | 180 | 150 | 130 | 110 | 90 | 80 | 82 | 60 | 60 |
50 | 420 | 320 | 320 | 280 | 200 | 200 | 210 | 160 | 160 | 125 | 100 | 100 | 95 | 70 | 70 |
Maximum Vibration Acceleration of Single Bearing
D | Diameter Series(0) | Diameter Series(2) | Diameter Series(3) |
mm | Z | Z1 | Z2 | Z3 | Z | Z1 | Z2 | Z3 | Z4 | Z | Z1 | Z2 | Z3 | Z4 |
3 | 35 | 34 | 32 | 28 | 36 | 35 | 32 | 30 | - | 37 | 36 | 33 | 31 | - |
4 | 35 | 34 | 32 | 28 | 36 | 35 | 32 | 30 | - | 37 | 36 | 33 | 31 | - |
5 | 37 | 36 | 34 | 30 | 38 | 37 | 34 | 32 | - | 39 | 37 | 35 | 33 | - |
6 | 37 | 36 | 34 | 30 | 38 | 37 | 34 | 32 | - | 39 | 37 | 35 | 33 | - |
7 | 39 | 38 | 35 | 31 | 40 | 38 | 36 | 34 | - | - | - | - | - | - |
8 | 39 | 38 | 35 | 31 | 40 | 38 | 36 | 34 | - | - | - | - | - | - |
9 | 41 | 40 | 36 | 32 | 42 | 40 | 37 | 35 | - | - | - | - | - | - |
10 | 43 | 42 | 38 | 33 | 44 | 42 | 39 | 35 | 30 | 37 | 44 | 40 | 37 | 32 |
12 | 44 | 43 | 39 | 34 | 45 | 43 | 39 | 35 | 30 | 47 | 45 | 40 | 37 | 32 |
15 | 45 | 44 | 40 | 35 | 46 | 44 | 41 | 36 | 31 | 48 | 46 | 42 | 38 | 33 |
17 | 46 | 44 | 40 | 35 | 47 | 45 | 41 | 36 | 31 | 49 | 47 | 42 | 38 | 33 |
20 | 47 | 45 | 41 | 36 | 48 | 46 | 42 | 38 | 33 | 50 | 48 | 43 | 39 | 34 |
22 | 47 | 45 | 41 | 36 | 48 | 46 | 42 | 38 | 33 | 50 | 48 | 43 | 39 | 34 |
25 | 48 | 46 | 42 | 38 | 49 | 47 | 43 | 40 | 36 | 51 | 49 | 44 | 41 | 37 |
28 | 49 | 47 | 43 | 39 | 50 | 48 | 44 | 41 | 37 | 52 | 50 | 45 | 42 | 38 |
30 | 49 | 47 | 43 | 39 | 50 | 48 | 44 | 41 | 37 | 52 | 50 | 45 | 42 | 38 |
32 | 50 | 48 | 44 | 40 | 51 | 49 | 45 | 42 | 38 | 53 | 51 | 46 | 43 | 39 |
35 | 51 | 49 | 45 | 41 | 52 | 50 | 46 | 43 | 39 | 54 | 52 | 47 | 44 | 40 |
40 | 53 | 51 | 46 | 42 | 54 | 52 | 47 | 44 | 40 | 56 | 54 | 49 | 45 | 41 |
45 | 55 | 53 | 48 | 45 | 56 | 54 | 49 | 46 | 43 | 58 | 56 | 51 | 47 | 44 |
50 | 57 | 54 | 50 | 47 | 58 | 55 | 51 | 48 | 45 | 60 | 57 | 53 | 49 | 46 |
55 | 59 | 56 | 52 | 49 | 60 | 57 | 53 | 50 | 47 | 62 | 59 | 54 | 51 | 48 |
60 | 61 | 58 | 54 | 51 | 62 | 59 | 54 | 51 | 48 | | 61 | 56 | 53 | 50 |
Company Profile
We are Ningbo Kent Bearing Co., Ltd, one of the leading high-quality bearing manufacturer and
supplier, established in 2003.
We registered the BUGAO Bearing trademark in 2003 and specialize in
deep groove ball bearings
for electric motors, automobiles, household appliances, power tools,
pumps, motorcycles, heavy vehicles,
machines and more.
The company has advanced assembly production lines and perfect
quality inspection center, and we
also passed ISO 9001: 2015 quality certification. We have an annual
production capacity of 30 million sets
of high quality bearing. Because of the company currently has more
than 20 automatic production lines,
all kinds of testing equipment and inspection equipment. We have
professional and technical personnel
with senior titles accounted for 20%. And we also continue to draw
domestic and foreign professional and
technical personnel. At present, we have own R&D center, which
has always been researching new
technology and more advanced equipment on bearing production and
inspection to improve the bearing's
quality and enhance the production efficiency. We have always been
aiming to make No.1 quality bearings
in the world.