Understanding Fits and Tolerances

The video tutorial from Codes and Standards Academy covers the concepts of limits, fits, and tolerances in engineering. It begins with an introduction to dimensions and sizes, explaining design size, basic size, and actual size. The video then delves into limits and allowances, discussing high and low limits, and the difference between clearance and interference. Tolerance and deviation are explained, including unilateral and bilateral tolerances. The tutorial also covers different types of fits, such as clearance, interference, and transition fits, and their applications. Finally, it explains fit systems, including hole basis and shaft basis systems, and concludes with a call to action for viewer engagement.

What is the term for dimensions that are in contact when parts are assembled?

• Mating dimensions

• Free dimensions

• Basic size

• Design size

What is the intentional difference between hole diameter and shaft diameter called?

• Allowance

• Basic size

• Deviation

• Tolerance

Which type of tolerance lies only on one side of the basic size?

• Negative tolerance

• Positive tolerance

• Unilateral tolerance

• Bilateral tolerance

What is the purpose of a zero line in tolerance zones?

• To represent the maximum size

• To indicate the basic size

• To show the minimum size

• To define the tolerance range

What is the term for the degree of tightness between mating parts?

• Fit

• Deviation

• Allowance

• Tolerance

Which type of fit always provides a positive assembly between mating parts?

• Interference fit

• Transition fit

• Clearance fit

• Tight fit

What is the application of a slack running fit?

• Gear trains

• Bearing power

• Loose pulleys

• High precision machinery

Which fit requires considerable pressure to assemble a hole in a shaft?

• Medium force fit

• Tight fit

• Shrink fit

• Loose fit

What is the characteristic of a transition fit?

• Always tight

• May provide either clearance or interference

• Always interference

• Always clearance

In which system is the size of the hole kept constant?

• Shaft basis system

• Hole basis system

• Clearance system

• Interference system