Application life requirements are another key consideration in the selection process. Loads may also vary in their magnitude and direction. Does the application require 10,000 hours of maintenance free running or will the motor only run 200 hours in the next 20 years? Table 2.1 Bearing selection procedure precision, rigidity and critical speed, etc. Selection of linear bearings and guides The sizing and selection process is similar but not exactly the same for round and profile rail bearings. 3. 2.1 Flow Chart for Selection of Rolling Bearings A007-023E.indd 16-17A007-023E.indd 16-17 111/20/13 4:49:36 PM1/20/13 4:49:36 PM A LOADS SELECTION CALCULATION OF THE EQUIVALENT LOAD For the calculation, the resultant of the radial loads FR is transposed into an equivalent axial load using a factor KR as follows : For standard slewing ring : if : F R < 0,25 FA if : 0,25 < FR < 1 F A if : FR > 1 FA † TILTING MOMENTS (bending) : in planes parallel to the rotation axis. Roller bearings exhibit less elastic deformation than ball bearings. For these reasons, bearing clearances are specified as “vertical clearance” and must be measured at 90 degrees to the split line. Bearing Selection A-13 Fig. 2. View 10.3 Selection and calculation of rolling bearings.pdf from ME 221 at Nanjing University of Aeronautics and Astronautics. 4-21 BEARING SELECTION LOAD CAPACITIES & LIFE CALCULATIONS Simple life/load estimations can be derived from the Radial Load chart. The key components that could pose a concern to the life of a motor include the bearings, the brushes, and the commutator. NTN Bearing Technical Calculation Tool Usage Method 3／62 ¡Bearing basic rating life based on JIS (L10h) or modified rating life that takes into accounta ISO (L10mh) ¡Two bearing rows ¡Up to three load centers (input item) ¡Can be selected by entering the boundary … This procedure is commonly applied to deep groove ball bearings, Shaft diameter to calculate the shaft surface speed. the Ball Bearing Company of Boston with seven other major ball bearing and ball-making equipment manufacturers. §10.3 Selection and calculation of rolling bearings 1. Approximate unit loading pressure (PSI or Newtons /m2).” Scott adds that it would be best to also have additional information, including: Bearing length, number of bearings and rotor weight (to calculate the bearing pres-sure to verify the load). The best method of measurement is with a dial bore gage that measures the bearing inside iameter when the bearings are installed at the specified torque without the shaft in place. Furthermore, in some cases, bearings are given a load in advance (preloaded) to increase their rigidity. bearing selection procedure Fig. Load Calculation & Selection of Bearing for Low Pressure Compressor (LPC) For Al -31FP Engine Narayan Parida1*, Siva Sankara Raju R 2, K. C. Rath3 1* (M.Tech, MSD student, Department of Mechanical Engineering, GIET, Odisha, INDIA ) Measurements should be 2. How to select 2.1 possible. of the bearing. Loads acting on linear bearings and guides can be vertical loads, horizontal loads or pitch roll or yaw moment loads, or any combination thereof. Temperature of the oil in the bearing. However, if a more specific estimation is desired, the life of a bearing can be calculated by the following formula: The company used the SRB Diamond trademark. Table 2.1 summarizes a typical bearing selection procedure, and Table 2.2 gives an example flowchart according to which considerations are made to select an optimal main spindle bearing for a machine tool. SRB made many contributions to the advancement of anti-friction bearings; most notably, the development of 52100 steel, a high carbon, high chrome alloy steel that greatly improved bearing life.