What is the advantage of a woodruff key?
Advantages Of A Woodruff Key Include: Ideal for high speed rotating assemblies. Eliminates milling near shaft shoulders reducing stress concentrations at the shaft end. Deeper seat in the shaft reduces risk of rolling out of key seat. Provides a more exact fit, reducing play in the key seat.
How tight should a woodruff key be?
It is important for key to be somewhat snug and stable in the key seat. If key is not snug/stable then key can easily slide out of key seat due to the curved profile on the bottom. This is very inconvenient in cases where it is difficult to see as the pulley is installed.
Why is it called woodruff key?
ETYMOLOGY OF THE WORD WOODRUFF KEY Named after the Woodruff Manufacturing Co, in Hartford, Connecticut, who first manufactured it in 1892.
What application often uses a woodruff key?
What application often uses a woodruff key? Woodruffs keys are commonly used in machine tools and, for example, between the flywheel and crankshaft of a small internal combustion engine, where the drive depends largely on the fit between the shaft and the conical rugged flywheel hub.
What are the advantages and disadvantages of a woodruff key?
Disadvantages of woodruff key : The extra depth of keyways in the shaft increases stress concentration and reduces its strength. The key does not permit axial movement between the shaft and the hub.
Do Woodruff keys wear out?
Woodruff keys tend tend to last forever unless they develop a bit of looseness which then develops quickly. Check the keyways (both in the shaft and in the gear).
How do you size a woodruff key?
The height of a Woodruff Key is less than half its nominal diameter. Distance Below Center is the distance from the nominal diameter centerline to the top of the Woodruff Key.
What is Kennedy key?
The Kennedy key consists of two square keys. The hub is bored off the centre and the two keys force the hub and the shaft to a concentric position. Kennedy key is used for heavy duty applications.
What is the difference between keys and splines?
The main difference between splines and keys is that splines are integral with the shaft but keys are inserted between shaft and hub. As compared with one or two keys used for load transmission, there are usually four or more splines on a shaft.
Can you harden key steel?
As a bright drawn steel bar it is uncommon to harden key steel. In its supply condition key steel has an approximate tensile strength of 500 to 700N/mm2. If heat treatment is a requirement, key steel can be heat treated by conventional methods and flame or induction hardening.
Are there metric Woodruff keys?
Metric Woodruff Keys are semicircular keyways used to lock rotating elements onto shafts.
What is a woodruff key used for?
Woodruff Keys are used for locking gears and pulleys to shafts. On the shaft, they fit into a keyseat, which is a circular pocket that retains the key. An exposed portion of the key fits into a rectangular groove, often called the keyway, in the gear or pulley.
How do you press a woodruff key?
Since woodruff keys are made to tight tolerances, they often require a press fit into its seat. This is done by lightly tapping the flat, protruding face of the key with a hammer or mallet until the key is seated firmly.
What is the difference between Full Radius and flat bottom Woodruff keys?
Full radius woodruff keys require precision of the seat groove as contact can occur between the woodruff key and the bottom of the seat causing interference and the key to protrude from the groove higher than desired. Flat bottom woodruff keys have the same profile as standard woodruff keys, however, the bottom of the key has been shaved flat.