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Bearing is the support of rotating shaft or movable part of various machinery. It is widely used in Its Inner Diameter agricultural machinery such as agricultural vehicles, tractors, diesel engines, motors, threshers and so on.
The bearing code is commonly used in the purchase of bearings, but the Its Inner Diameter bearing code is more complex. If the palm of the agricultural machinery holds the law of identifying the bearing code, the purchase will be easy.
Generally, common bearings are some standard models, code “0”, tolerance grade “g” (common grade). The first Its Inner Diameter section of general bearings can not be written, so its code is mostly represented by 7 digits of the basic code.
Here is an example to illustrate the meaning of bearing code: for example 7002136 (135 series diesel engine shaft main bearing), its basic code is identified from right to left. The two digits of “36” represent the inner diameter, and its calculation method is 36 × 5 = 180 mm; “1” indicates diameter series extra light; “2” means cylindrical roller bearing;
“00” indicates the bearing structure, and the outer ring has no flange; “7” indicates that the width series is Its Inner Diameter narrow. If the manipulator selects 7-digit bearing codes of other standard models, this type of push can be used.
The bearing inner diameter is represented by the right end and the second digit in the basic code. The bearing inner diameter is divided into standard and non-standard inner diameter. The difference is that the non-standard inner diameter is not an integer or an integral multiple of 5. In order to facilitate the purchase of the machine operator, examples are given:
1. The bearing with an inner diameter of less than 9 mm is represented by Its Inner Diameter the actual size of the number of digits at the right end. For example, bearing No. 18 has an inner diameter of 8 mm.
2. The bearing inner diameter is 10mm-17mm, which is expressed by a fixed number. For example, for bearing numbers 100, 201, 302 and 403, the Its Inner Diameter inner diameter code is the right end, the two digits are 00, 01, 02 and 03, and the inner diameters are 10, 12, 15 and 17 mm respectively.
3. The bearing inner diameter is Its Inner Diameter 20mm-480mm (except 22, 28 and 32), which is expressed by the quotient of the inner diameter dimension divided by 5.
4. The bearing inner diameter above 500mm (22, 28 and 32) is expressed by fraction, the denominator Its Inner Diameter represents the inner diameter, and the numerator represents the size series, type and structural form of the bearing. For example, bearing No. 30031 / 560 has an inner diameter of 560mm, and so on.