Determining Keyway Limits: What is the Process?

  • Thread starter Thragnak
  • Start date
  • Tags
    Limits
In summary, the process for determining limits of keyways is to find the width of the keyway and then use the tolerances in tables in the Machinery's Handbook to determine the limits of the key.
  • #1
Thragnak
2
0
Hello guys, first post here so don't get mad if I have place it in the wrong area.
Going through one of my lessons earlier I was learning about the limits and fits of holes and shafts, determining the tolerances of certain objects kind of stuff. It was also briefly mentioned that you could determine the limits of keyways by using a similar process, this was not gone into in great detail so I do not really understand it a whole lot. What is the process for determining limits of keyways if you just know the width of it?
I am sorry if I have been a little vague, but I was not sure how else to explain it.
Thanks, Thrag.
 
Engineering news on Phys.org
  • #2
Welcome to PF.

There are cases where the joint is tight and the key is only critical during assembly as an angular relationship must be maintained. The accuracy of key fit then decides accuracy of assembly. Often on machine timing shafts a semicircular woodruff key is used with a locking taper shaft coupling. http://en.wikipedia.org/wiki/Key_(engineering)#Woodruff_keys

There are other cases where the key transfers mechanical energy, usually through a long rectangular parallel key. If parallel keys do not fit well in their ways then the movement will repeatedly hammer or slog out the key and/or it's way. This is a very common mode of failure in mechanical equipment. The quality of the machinined fit of shaft, key and pulley decide the lifetime of the equipment. http://en.wikipedia.org/wiki/Key_(engineering)#Parallel_keys

Refine your question if you require a more refined answer.
 
  • #3
I would say could you explain a bit more on what you mean by the 'limits of keyways' ? Are you talking about its dimensions ? Generally keyways for a certain shaft size are found in standard charts employed by OEMs.
 
  • #4
I am sorry if it my question wasn't very specific, this is not a topic I know a huge amount on.
Yes I am talking about dimensions, where would I be able to find out more about the standard charts employed by OEM's? I had a quick search but was unable to find anything that seemed related.
Thank you for the links Baluncore, they have really clarified the topic for me!

Cheers,Thrag
 
  • #5
Machinery's Handbook, 28th Edition, has a section on “Keys And Keyseats”. It includes tables with tolerances.
 

FAQ: Determining Keyway Limits: What is the Process?

What is a keyway?

A keyway is a groove or slot on a shaft or hub that allows a key to be inserted. It is used to transmit torque and prevent rotation between the two parts.

How do you determine the limits of a keyway?

The limits of a keyway are determined by the size and shape of the key, as well as the dimensions of the shaft or hub. The keyway should be wide enough to accommodate the key, but not too wide so that it loses its effectiveness in transmitting torque.

What factors affect the limits of a keyway?

The size and material of the key, the material and dimensions of the shaft or hub, and the amount of torque being transmitted are all factors that can affect the limits of a keyway.

What is the purpose of determining the limits of a keyway?

Determining the limits of a keyway ensures that the key fits properly and can effectively transmit torque without causing damage to the shaft or hub. It also helps to prevent loosening or slipping of the key.

How do you calculate the limits of a keyway?

The limits of a keyway can be calculated using standard engineering formulas that take into account the dimensions of the key, the shaft or hub, and the amount of torque being transmitted. It is important to consult industry standards and guidelines for accurate calculations.

Similar threads

Replies
3
Views
2K
Replies
25
Views
3K
Replies
1
Views
3K
Replies
1
Views
3K
Replies
8
Views
5K
Back
Top