Types of Keys
- 1. Machine Design & Industrial Drafting (2141907) Mechanical Department Sem.: 4th D (D2) Guided By: Pro. Ashish Majithiya Prepared By: Gohel Sajan P. (160123119010)
- 2. What is key ????? A key is a machine element used to connect a rotating machine element to a shaft. It is always inserted parallel to the exist of the shaft. A keyway is a slot in a shaft and hub of the pulley to accommodate a key.
- 4. Sunk key • The sunk key are provided half in the keyway of the shaft and half in the keyway of the hub . • The sunk key are of the following types: 1. Rectangular key 2. Square key 3. Parallel key 4. Gib-Head key 5. Feather key 6. Woodruff Key
- 5. 1. Rectangular Key • A key is a piece of mild steel inserted between the shaft and hub of the pulley to connect these together in order to prevent relative motion between them. The key has taper 1 in 100 on the top side only.
- 6. 2. Square Key • The only difference between a rectangular sunk key and a square sunk key is that its width and thickness are equal. i.e , W=t=d/4
- 7. 3. Parallel key • The parallel sunk key may be of rectangular or square section uniform in width and thickness throughout. • It may be noted that a parallel key is a taperless and is used where the pulley, gear or other mating piece is required to solid along the shaft.
- 8. 4. Gib-Head Key • It is a rectangular sunk key with a head at one end known as Gib-Head Key. • It is usually provided to facilitate and removal of key.
- 9. 5. Feather key • A key attached to one member of a pair and which permits relative axial movement is known as feather key. • It is a special type of parallel key which transmits a turning movement and also permits axial movement.
- 10. 6. Woodruff Key • The woodruff key is an easily adjustable key. • It is piece from a cylindrical disc having segmental cross-section in front view of figure. • This key is largely used in machine tool and automobile construction.
- 11. Saddle keys • The saddle key are of the following two types: • Flat saddle key • Hollow saddle key 1.Flat saddle key:- A flat saddle key is a taper key which fits in a keyway in the hub and is flat on the shaft as show in figure.
- 12. 2. Hollow Saddle Key :- A Hollow saddle key is a taper key which fits in a keyway in the hub and the bottom of the key is shaped to fit the curved surface of the shaft. • It is used as a temporary fastening in fixing and setting cams etc.
- 13. Tangent Keys • The tangent key are fitted in a pair at right angles. • Each key is to withatand torsion in one direction only. • sThey are used in large heavy duty shaft.
- 14. Round key • The round keys, are circular in section and fit into holes drilled partly in the shaft and partly in the hub. • They have advantage that their keyways may be drilled and reamed after the mating parts have been assembled.
- 15. Splines • Sometimes, keys are made integral with the shaft which fit in the keyways broached in the hub. Such shafts are known as splined shafts. • The Splined shaft are used when the forces to be transmitted is large in proportional to the size of the shaft.
- 16. Thank You