7.6 Flashcards
What is a clearance fit
The hole is always bigger than the shaft
Always has some play
What is a clearance fit divided into
Running
Free running
What does a transition fit mean
Tolerance of hole and shaft can over lap
Could be clearance or interference
What is transition fit sub divided into
Push fit
Light press fit
What does interference fit mean
The shaft is bigger than the hole
What is interference fit subdivided into
Drive
Press
Force fit
What is an extreme version of interference fit and how do you do it
Shrink fit
By heating the hole to expand it and then putting the cold shaft in
What standard do fits and clearance follow
BS4500
What letter are holes allocated
Capital letter followed by a number
What letter are shafts allocated
Lower case letter
What does the letters H or h mean
Zero fundamental deviation (only tolerance in one way)
For a shaft if it goes h k n p does p mean the shaft has got bigger
Yes as the letter ascend the size gets bigger
For a hole if it goes H K N P does P mean the hole has got bigger
Hole gets smaller as it acends
What are the four dimensions on a wear table
Dimensions new
Permissible worm dimensions
Clearance new
Permissible worn clearance
What is a DTI
Dial test indicator
It is a precision instrument that determines the amount of movement between certain components
