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1. Classification by rolling bearing (imported bearing) structure type
(1) Imported bearings can be divided into:
1) Radial bearing —- it is an important rolling bearing used to bear radial load, and its nominal contact angle is from 0 to 45. According to different nominal contact angles, it is divided into radial contact bearing – radial bearing with nominal contact angle of 0: radial angular contact bearing – radial bearing with nominal contact angle greater than 0 to 45.
2) Thrust bearing —- it is an important rolling bearing used to bear axial load, and its nominal Classification Methods contact angle is greater than 45 to 90. According to different nominal contact angles, it is divided into axial contact bearing –
thrust bearing with nominal contact angle of 90: thrust angle contact bearing – thrust bearing Classification Methods with nominal contact angle greater than 45 but less than 90.
(2) According to the type of rolling element, bearings are divided into:
1) Ball bearing – the rolling element is a ball:
2) Roller bearing —- the rolling element is a roller. According to the variety of rollers, roller bearings are divided into: Classification Methods cylindrical roller bearings – rolling elements are cylindrical roller bearings, and the ratio of length to diameter of cylindrical rollers is less than or equal to 3;
Needle roller bearing – the rolling element is a needle roller bearing. The ratio of the length to the diameter of the needle roller is greater than 3, but the diameter is less than or equal to 5mm; Tapered roller bearing —- the rolling element is the bearing of tapered roller; Self aligning roller bearings are spherical roller bearings one by one.
(3) The imported bearings are divided into:
—- the raceway is spherical and can adapt to the angular deviation Classification Methods and angular movement between the axis lines of the two raceways;
2) Non self aligning bearing (rigid Classification Methods bearing) — a bearing that can resist the axial line angle offset between raceways.
(4) According to the number of columns of rolling elements, imported bearings are divided into:
1) Single row bearing – bearing with one row of rolling elements;
2) Double row bearing – bearing with two rows of rolling elements;
3) Multi row bearings —- bearings with more than two rows of rolling elements, such as three row and Classification Methods four row bearings.
(5) Imported bearings are divided into:
1) Separable bearing —- bearing with separable parts;
2) Non separable bearing — after the final matching of the bearing, the ferrule cannot be freely Classification Methods separated.
(6) Imported bearings can also be divided into various structural Classification Methods types according to their structural shapes (such as whether there is a filling groove, whether there is an inner ring, an outer ring and a ferrule, the structure of the retaining edge, and even whether there is a maintenance frame).
2. According to the size of rolling bearing, the bearing is divided into:
(1) Miniature bearing — bearing with nominal outer diameter size less than 26mm;
(2) Small bearing — bearing with nominal outer diameter of 28-55mm;
(3) Small and medium-sized bearings — bearings with nominal outer diameter of 60-115mm;
(4) Medium and large bearings — bearings with nominal outer diameter size of 120-190mm
(5) Large bearing — bearing with nominal outer diameter of 200-430mm;
(6) Extra large bearing —- bearing with nominal outer diameter of more than 440mm.