Four row circular cone roller bearings abnormal damage of - — The baffle

Four row circular cone roller bearings abnormal damage of - — The baffle - 2018 07 - 15 among the six roller cold rolling mill roller mill operation side 3806/160 four row circular cone roller bearings rolling body and outer fatigue spalling damage occur in a short period of time, bearing damage lock phenomenon, the use of bearing and assembly work to bring inconvenience, caused large economic loss. Aiming at this problem, bearing manufacturers and technical personnel through to the bearing after testing, the indicators in the exclusion of bearing under the premise of their own reasons for the plant's bearing assembly site for tracking all the time, and the scene to participate in the installation, disassembly and maintenance, by tracking found following a series of related problems: one, bearing structure and characteristics of the type 380000 this kind of bearing structure is compact, basic performance and double row circular cone roller bearings basic same, can withstand the radial and axial joint load, the basic structure consists of two double row inner ring components ( Rolling body, cage and inner ring) And a double outer ring and two single outer ring, two side baffle, an inner circle of insulation. Factory both inside and outside the outer ring, inner ring and baffle are printed character symbols, when installation, must according to the characters of the symbols in the order of load bearing box. Not any swap, to prevent the bearing clearance changes. Second, the assembly structure of the three roll system, assembly way 1, four row tapered bearing is separable bearing, outer ring, baffle, and the rolling body components ( Rolling element and cage and inner ring) , when the assembly installed side outer ring - in turn A, roller components - A, in the outer circle of AA, outer ring, inner ring, rolling body components - E, outer baffle BB outer ring - the last side The case E all installed such as bearings, then the bearing box pressure on the gland. Bearing load bearing body work is done, the entire assembly order, in addition to the appeal must be installed in the gland step as the core, must guarantee gland effectively pressure on end face and the bearing outer ring end face, namely, can't give too much pre-tightening force caused by prestressing force to prevent bearing outer baffle deformation caused by bearing installed the game changes, and can't appear too big axial clearance, must guarantee gland of end face with bearing end face, usually after the end of the mouth come into contact with the bearing section need to measure ( Plug gauge) Gland and bearing the gap of end face of the S value, and then add appropriate thickness adjustment gasket to ensure gland with bearing face, gasket ( Rigid) The thickness of H = ( S+0. 05) 。 But the four row tapered roller bearing assembly high C value, deviation is bigger, more than 0. 5 mm, namely must each assembly will need to measure the line, to ensure that the gland and the end of the bearing to cooperate. 2, bearing assembly to bearing box, and then lifting ( Bearing inner ring with roller diameter clearance fit) Directly to the bearing suits at the end of the roll diameter through the whole bearing axial locking ring precise locking on the roll, thus forming bearing box, a combination of roller and bearing assembly. Four, bearing damage form of bearing lock after burning loss is often the third column and column 2 damage, and also the corresponding damage retainer and the outer ring. Five, the phenomenon analysis of composite bearing characteristics, the installation process and damage phenomenon, can be analyzed, when the rolling bearing axial force of the two directions, when the axial force was passed from the side of bearing axial force are respectively a third column under axial force in one direction, by 2/4 columns under axial force in one direction, and from the picture and two-thirds of the bearing damage rule column is easy to damage, which means the bearing during operation, when passed the axial force is not the two columns of the scroll body at the same time bear the axial force of a direction, but abnormal single row bearing, resulting in the bearing axial load drop 50%, will inevitably lead to abnormal loss of bearing. Further analysis the cause of single row bearing and the bearing structure can be analyzed out, only bearing assembly error or baffle in height after wear, will cause the axial force transfer blocking, causes the single roller bearing, so check the damaged bearing inner circle, found space ring wear. This analysis conclusion, think the abnormal damage of bearing is of shorter baffle wear, lead to the axial force transfer block, single row bearing and result in bearing damage. And the baffle wear mostly due to the outer ring and gland not compaction, clearance is too large and the lubrication effect is poor. Six, corrective actions 1, improve the hardness of bearing inner ring insulation. 2, strengthen the lubrication of baffle place measures. 3, improve the assembly accuracy, be sure to assemble a measurement at a time. （ Source: jiangsu emperor mond rolling mill bearing)