Keys and Its Function – Design of Machine

Keys and Its Function – Design of Machine

Hello friends here in this video we will see what is a key what are different types of key and what is the function of a key so let us get started with the definition part first key it is defined as a piece of metal which is used to connect a shaft and hub and this hub is also called as boss or sleeve so it is defined as a piece of metal which is used to connect a shaft and hub next key is a temporary joint or connection like nuts and bolts so it is our temporary connection next key are subjected – shearing and crushing next the material for shaft and key are taken as same so here I have written some points about key that it is defined as a piece of metal which is used to connect a shaft and hub that hub is also called as boss or sleep next key is a temporary joint or connection like nuts and bolts key are subjected to shearing and crushing the material for the shaft and key are taken as same so here was some brief points regarding key now I will draw a diagram of a simple key and explain how it is used as a temporary connection for that purpose your suppose we have a shaft which is having is some value of its diameter now that shaft will also have some lengths like this now as we can see here this is a shaft next year some groove is made this groove is called as keyway next here I am drawing another member which would be called as a hub now this is either called as hub or it is called as sleeve or you can say it is also called as boss now the key way is there in the shaft a similar kind of key way is also there in this boss so here I can say that this is also a key way next here I am drawing this member and it is called as a key so now how the connection takes place see if I want to connect this shaft and sleeve what I will do I will just put this shaft inside the hub next this key I’ll say that its thickness is small T so half of the thickness that is this key way has thickness as T by 2 the key way which is there in this lever boss this also has thickness of T by 2 so the thickness of the key is divided into two parts half of that is in the shaft and the remaining half is there in the boss and this shaft is inserted inside this boss and then we are inserting the key so that forms a complete connection and with that complete connection we can say that this key has connected the shaft and the hub and I can see that if I draw this diagram now here we have the diagram which I can explain it this is the sleeve or boss we have inserted the shaft so now here they are connected and inside that we would be inserting this key so the key will be somewhere here it would be inserted inside this so this is the key so here when the key is inserted we complete this temporary joint and after the function is over we can remove this key as well so this was regarding the functioning of the key

52 thoughts on “Keys and Its Function – Design of Machine

  1. please make a general video on design of gear box. so that all parameters would come i.e keys shafts gears and all stuff.

  2. sir please add some lecture about design of , V belt drive, Pulley chain , couplings and IC engine

  3. sir, you told thickness of key should be divided into half-half into hub and shaft. shall we use keys in different ratio? like making less or more depth of key way in shaft and using the key the same thickness what total thickness comes in hub and shaft. if it fails what may be the reason?

  4. Thanks a lot! I've been trying to find ways to interconnect rotating objects and kept coming across these terms. This was a very concise and helpful explanation.

  5. Sir! If the load is inclined load on the SHAFT at 45°. Then How will it Solve ?
    Sir, Please make videos on this types of question.

  6. please help me, A transmission shaft is supported on two bearings 450mm apart. Two pulleys C and D are located on the shaft at distance of 100mm and 300mm respectively to the right of the left hand bearing. Power is transmitted from C and D. The diameter and weight of pulley C are 200mm and 600N and those for D are 300mm and 750N respectively. Ratio of belt tension is 2 for both the pulleys. Power to be transmitted by the shaft is 25KN at 300 rpm. The driver from C is vertically downwards while from D the driver is horizontal. The shaft is of steel allowable shear stress is 47.5N/mm2. Design the shaft and draw all required diagrams

  7. U r explanation is very very very good sir…sir ies syllabus is also upload we want to watch sir…..

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