 Hello everyone, myself Sachin Rathod working as assistant professor in mechanical engineering department from Valjunstorp Technology, Sallapur. Today, we will concern with the rolling contact bearing part 4. So, previous to this session, we had seen the introduction part about the rolling contact bearing. Next, we had seen how to find out the static load carrying capacity of the bearing. Now, we will see in the part 4 at the end of this session, the learner will be able to select the bearing from manufacturing catalog. In this slide, we are going to see the selection of the bearing from manufacturing catalog. So, in that, the step number 1 is to calculate the radial force and the axial force acting on the bearing. So, as the different forces acting on the shaft, so that force we have to consider that is acting on the bearing. So, we have to calculate the radial force and the axial force which is acting on the bearing. Step number 2 is select the suitable type of the bearing for the applications. So, for this purpose, certain guidelines are there. So, already we have seen these guidelines in the first PPT or the part 1 of the rolling contact bearing. So, just in the shot, we will see what are the guidelines. So, if the load is medium and low radial loads, if the low and medium radial loads are acting on the bearing, then we can select the ball bearing. If the heavy radial loads are acting, then we can select the roller bearing. If there is a misalignment between the shaft, at that time, we can prefer the self-aligned ball bearing or if the load is high, that is in which the misalignment is going to occurs at that time, we can select the self-aligned spherical roller bearing. Then if the low or medium thrust load is there, that is the load which is acting along the axis of the shaft, that is called as the thrust load, at that times we can prefer the thrust ball bearing or if the heavy thrust load is there, at that times we can select the cylindrical roller thrust bearing. Then the step number 3 is that, determine the values of X and Y, that is the radial and the thrust factor from the manufacturing catalog. So, you can pause this video and you can think about this. If you already calculated the value of radial and the thrust radial and the axial force on the bearing, then why it is necessary to calculate the factors of radial and the thrust. So, you can think about this. So, this is the table from which we can select the value of X and Y factors, that is the radial and the thrust factor from the manufacturing catalog. So, this catalog I have taken from the VB Bhandari book and which is already which is available in the standard design data book. So, from this catalog we have to find out the value of the radial and thrust factor. So, already we had calculated the axial force acting on the bearing and the radial force acting on the bearing and C naught is nothing but the static load carrying capacity of the bearing. So, this value we are knowing. So, just calculate the value of from the first row that is the F A by C naught, then find out the value of F A by F R. So, based on this relation, this is the E is nothing but the constant value. So, based on this relation we have to select the value of the X and Y. Step number 4, calculate the equivalent load. So, by using this equation that is a P or it is also called as P is equal to X into V into F R plus Y into F A. So, from which we are knowing the value of the F R and F A that is the radial and the axial force and X and Y are the radial and the thrust factors. So, that is already in the previous slide we had seen how to calculate the value of X and Y. V is nothing but the rest factor that is depending upon your whether your the inner race is going to rotate or the outer race is going to rotate. If the inner race is going to rotate at that times we can use V is equal to 1 and if your the outer race is rotated and the inner race is stationary at that times we can use V is equal to 1.5. So, then next the step number 5, we have to decide the expected life of the bearing in million revolution. So, depending upon the past experience they had calculated the value of the expected life of the bearing. So, this is a catalog I have taken from the VB Bhandari book. So, this is a standard catalog from which we have to select the value of the expected life of the bearing. So, in this table the two columns are there the first one is the wheel applications and second column is about the life of the bearing in million revolution. So, they have taken a different applications are like that if we are using the bearing in the automobile's cars or if you are using the bearing in the trucks trolley cars or the railroad cars at that time the lives are the difference. So, the values of the life corresponding to the different application they had given us in this catalog. So, we have to select the proper applications depending upon the proper application you have to select the life of the ball bearing from this catalog. Then the step number 6, in this step number 6 we have to calculate the dynamic load carrying capacity of the bearing. So, the relation between life and the dynamic load is already we had seen in the previous session that L is nothing but the life in million revolution is equal to C by P raise to K where the K is a constant term and the value of the K is equal to 3 for the ball bearing and 10 by 3 for roller bearing. And the remaining value the life so depending upon the applications we have to select the value of the life in million revolution that we had seen in the previous slide and P is nothing but the equivalent load that equivalent load we have to calculate by using the equation x into v into F r plus y into F a depending upon that we have to calculate the value of the equivalent load then you can easily get the value of dynamic load. So, here we have to consider the load factor so see that what is in by load factor the load factor we are using for calculating the required value of the dynamic load capacity according to the application. So, we have to select the value of the load factor depending upon the type of the drive if we are using the gear drive so in that the gear drive there are the 3 classification they have made for selecting this load factor. If the rotating machine free from the impact load then we can use the load factor ranging in between the 1.2 to 1.4 if the reciprocating machines are there at that times we can use the load factor as a 1.4 to 1.7 if the impact machines are there like a hamper hammer then we have to choose the load factor which is ranging in between 2.5 to 3.5 similarly if the belt drives are there in which I have to use the ball bearing at that times we have to select the appropriate load factor depending upon the type of the belt. Similarly, for the chain drive we have to use the load factor which is given in this table I have taken this table from the Webibandari book so while calculating the actual load that is the dynamic load acting on the bearing that is the value of the c is equal to p raised to 1 by k into sorry so we have to calculate the value of the c so for calculating the value of the c we have to multiply just rearrange these equations and we have to multiply with the load factor for getting the exact amount of the dynamic load which is acting on the bearing. Then the step number 7 in this step number 7 we have to select the bearing from the manufacturing catalog using the following input so this input they will provide you based on this we have to select the bearing specifications so this is the table for the bearing specification so in this tables see that what are the terms they are going to use in this table small d is nothing but the diameter of the shaft capital D is the outer diameter of the bearing b is nothing but the width of the bearing c is nothing but the dynamic load carrying capacity of the bearing c naught is nothing but the static load carrying capacity of the bearing and this is the designations we have to select depending upon this data so the input data are the type of the bearing shaft diameter and the dynamic capacity of the bearing so this table is going to provide the designation for the single deep single row deep group ball bearing if suppose if I am considering if the diameter of the shaft is 25 I have to select or I have to give the designation so if the diameter of the shaft we have to refer the first column for checking the diameter so if you observe that the diameter is 25 here then if I have calculated the value of the dynamic load as we have seen in the previous slide if the dynamic load if I am considering if it is 9000 Newton then I have to check where is the 9000 so here this c column that is the dynamic load carrying capacity so here check out 3120 then 7610 then next 11200 so we can choose the next value of this 9000 Newton so I can choose the value of the dynamic load which may be 11200 this value I have to check and based on that I have selected the designation of the bearing is 6005 so this is the procedure for giving the designation of the bearing so what the designations or the what is the specification of the bearing number so this is a bearing number that is a 6005 so what it indicates the bearing being a standard mechanical element it is designated by a number either 4 digit or the 5 digit so in which the last 2 digits specify the bore or the shaft size so if you observe that this last 2 digit that is a 04 it indicating the bore diameter or the shaft diameter see that last 4 digit all the 4 digits are the last 2 digits are the 040404 it indicating the size of the diameter just if I am going to multiply with the 5 we are getting the diameter of the shaft as a 20 then the third digit specify the series so if you observe that the third digit is 0234 similarly here the 0234 it indicates the series of the bearing then the fourth and the 50 digits indicates the type of the bearing so if you observe here the fourth or the 50 digit that is a 6 digit that is a 6 numbers is indicating for the deep groove ball bearing so I have taken this references for this video thank you all.