Product Details
Pillow Block Ball Bearing 40 mm Bore UCT204 Housing Bearing Shaft Bearing
The UCT204 consists of two main components:
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Housing:
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Made of cast iron or stamped steel, the housing provides a sturdy base for the bearing unit.
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It features a four-bolt mounting design, which ensures secure attachment to flat surfaces and enhances stability.
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The housing is designed to absorb vibrations and provide reliable support for the shaft.
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Insert Bearing:
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The insert bearing is typically a deep groove ball bearing (model 204).
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Made from high-quality chrome steel (GCr15), it offers excellent durability, wear resistance, and load-carrying capacity.
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The bearing is designed to handle both radial and axial loads, making it versatile for various applications.
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Sealing:
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The UCT204 can be equipped with rubber seals (2RS) or metal shields (ZZ) to protect the bearing from contaminants and retain lubrication.
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Seals help extend the bearing’s lifespan by preventing dust, dirt, and moisture from entering.
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Lubrication:
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The bearing is pre-lubricated with high-quality grease, ensuring smooth operation and reducing the need for frequent maintenance.
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Lubrication holes or fittings may be provided for easy re-lubrication in some designs.
2. Dimensions of UCT204 Bearing
The UCT204 follows standard dimensions (in millimeters):
Parameter | Dimension (mm) |
Bore Diameter (d) | 20 mm |
Outer Diameter (D) | 47 mm |
Bearing Width (B) | 14 mm |
Housing Hole Diameter | 20 mm |
Overall Length (L) | 104 mm |
Overall Width (W) | 80 mm |
Overall Height (H) | 46 mm |
Mounting Hole Spacing (A) | 70 mm |
Mounting Hole Diameter (B) | 11 mm |
Weight | Approximately 0.9 kg |
3. Applications of UCT204 Bearing
The UCT204 is widely used in various industries due to its durability and versatility. Common applications include:
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Conveyor Systems:
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Agricultural Machinery:
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Found in tractors, harvesters, and irrigation systems.
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Withstands harsh conditions such as dust, dirt, and moisture.
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Industrial Fans and Blowers:
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Supports rotating shafts in fans and blowers, ensuring smooth and efficient operation.
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Suitable for high-speed applications.
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Food Processing Equipment:
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Used in mixers, conveyors, and packaging machines.
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Stainless steel variants are available for corrosion resistance in wet or hygienic environments.
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Pumps and Compressors:
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General Machinery:


UCT Series Pillow Block Ball Bearings Parameters

Wide Application of Pillow Block Bearings

Customization Welcomed:
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We can printing your brand (logo,artwork)on the shield or laser engraving your brand on the shield.
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We can custom your packaging according to your design.
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All copyright owned by clients and we promised don't disclose any information.
Packing and Shipping:
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The deep groove ball bearings will be securely packaged individually, or tube packing or packed as customization packing
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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 Vibration 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 brand KYODO YUSHI | Product | Base oil | Usage range | Characteristics |
EXXON | Multemp SRL | Polyol ester+Diester | (-50,+150) | Excellent noise suppressantproperty and extended performance life |
Multemp PS | Diester+Refined mineral oil | (-50,+130) | Excellent low temperature performance,has outstanding noise suppressant property |
Multemp SM-B | Synthetic hydrocarbon | (-50,+200) | Long service life under high temperature,Excellent low temperature performance,has high speed operation,low noise property |
Multemp ET-K | SyntheticEther +Polyol ester | (-40≥,+200) | Has more extended life under high operating temperature condition |
MOBILE | Polyrex EM | Mineral grease | (-40,+180) | Long life and high temperature |
Beacon325 | Synthetic grease | (-54,+150) | General purpose grease |
Andok C | Channeling petroleum grease | (-27,+120) | Smooth running,long life with minimum migration |
CHEVRON | Mobil 28(MIL-G-81322) | Synthetic hydrocarbon | (-54,+177) | Wide temperature range,good low temperature torque |
Mobil HP | Lithium complex | (-30,+110) | Vibration,moderate speed and good corrosion resistance |
SHELL | SRI-2 | Mineral grease | (-30,+180) | High temperature range,good water resistance |
DUPONT | Alvania 2 | Mineral grease | (-35,+120) | Long life and high temperature |
RLQ #2 | Mineral grease | (-50,+150) | Low noise,high speed and high temperature |
KLUBER | ASONIC | Synthetic hydrocarbon | (-50,+140) | High temperature stability with good lubricity properties |
JINZHI | HANGU 2# | Mineral grease | (-20,+120) | Low noise |
HTHS | Mineral grease | (-40,+180) | High speed,low temperature,low torque and low noise |

The Radial Clearance of Bearings with Electric Motor Quality
Bore | CM |
Over | Including | Min | Max |
mm | inch | mm | inch | um | um |
10 | 0.3937 | 18 | 0.7087 | 4 | 11 |
18 | 0.7087 | 24 | 0.9449 | 5 | 12 |
24 | 0.9449 | 30 | 1.1811 | 5 | 12 |
30 | 1.1811 | 40 | 1.5748 | 9 | 17 |
40 | 1.5748 | 50 | 1.9685 | 9 | 17 |
50 | 1.9685 | 65 | 2.5591 | 12 | 22 |
Datas of the Mini-deep Groove Bearings Under No Load As Follows: | Tolerance in um |
Bore | Inch R Series | C2 | NORMAL | C3 | C4 |
Over | Including |
mm | inch | mm | inch | min | max | min | max | min | max | min |
2.5 | 0.0984 | 10 | 0.3937 | R2-R6 | 0 | 7 | 2 | 13 | 8 | 23 | 14 |
10 | 0.3937 | 18 | 0.7087 | R8-R10 | 0 | 9 | 3 | 18 | 11 | 25 | 18 |
18 | 0.7087 | 24 | 0.9449 | R12-R14 | 0 | 10 | 5 | 20 | 13 | 58 | 20 |
24 | 0.9449 | 30 | 1.1811 | R16-18 | 1 | 11 | 5 | 20 | 13 | 28 | 23 |
30 | 1.1811 | 40 | 1.5748 | R20-R24 | 1 | 11 | 6 | 20 | 15 | 33 | 28 |
40 | 1.5748 | 50 | 1.9685 |
| 1 | 11 | 6 | 23 | 18 | 36 | 30 |
50 | 1.9685 | 65 | 2.5591 |
| 1 | 12 | 8 | 28 | 23 | 43 | 38 |
Datas of the Mini-deep Groove Bearings Under No Load As Follows: | Tolerance in um |
Clearance Code | MC1 | MC2 | MC3 | MC4 | MC5 |
Clearance | min | max | min | max | min | max | min | max | min | max |
1 | 6 | 4 | 9 | 6 | 11 | 9 | 14 | 15 | 22 |
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.