Sunk keys: Type of sunk keys: Rectangular,Square,Parallel sunk,Gib-head,Feather,Woodruff.
Square keys are used for smaller shafts and rectangular faced keys are used for shaft diameters over 6.5 in or when the wall thickness of the mating hub is an issue.
The keyway in a shaft for a parallel key
The main advantage of the Woodruff key is that it eliminates milling a keyway near shaft shoulders, which already have stress concentrations .
The keyway in the hub has a taper that matches that of the tapered key.
A "Scotch key" or "Dutch key" also provides a keyway not by milling but by drilling axially into the part and the shaft, so that a round key can be used.
Keyseating can be done on a variety of different machines including a keyseater, a vertical slotting machine, a broacher, either a vertical or horizontal mill, or with a chisel and file.
The specific broach, bushing and guide are used for each given keyway cross-section, which makes this process more expensive than most of the alternatives. However, it can produce the most accurate keyway out of all the processes.
There are three main steps in broaching a
keyway: First, the workpiece is set on the arbor press and the bushing
is placed in the opening of the workpiece.
Keyseaters, also known as keyseating machines and keyway cutters, are specialized machines designed to cut keyways.
Parallel, tapered, and Woodruff keyways can be produced on a milling machine .
End mills or slotting cutters are used for parallel and tapered keyways, while a Woodruff cutter is used for Woodruff keyways.
The keyway is roughed out using a chisel and then filed to size; the key is tried frequently to avoid over filing. This technique is long, tedious, and rarely used anymore.
Square keys are used for smaller shafts and rectangular faced keys are used for shaft diameters over 6.5 in or when the wall thickness of the mating hub is an issue.
The keyway in a shaft for a parallel key
The main advantage of the Woodruff key is that it eliminates milling a keyway near shaft shoulders, which already have stress concentrations .
The keyway in the hub has a taper that matches that of the tapered key.
A "Scotch key" or "Dutch key" also provides a keyway not by milling but by drilling axially into the part and the shaft, so that a round key can be used.
Keyseating can be done on a variety of different machines including a keyseater, a vertical slotting machine, a broacher, either a vertical or horizontal mill, or with a chisel and file.
The specific broach, bushing and guide are used for each given keyway cross-section, which makes this process more expensive than most of the alternatives. However, it can produce the most accurate keyway out of all the processes.
Keyseaters, also known as keyseating machines and keyway cutters, are specialized machines designed to cut keyways.
Parallel, tapered, and Woodruff keyways can be produced on a milling machine .
End mills or slotting cutters are used for parallel and tapered keyways, while a Woodruff cutter is used for Woodruff keyways.
The keyway is roughed out using a chisel and then filed to size; the key is tried frequently to avoid over filing. This technique is long, tedious, and rarely used anymore.
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