LIMITS, FITS AND TOLERANCE TERMINOLOGY

What does ‘50’ represents in 50H8/g7?

• Basic size

• Actual size

• Maximum limit of size

• Minimum limit of size

Which of the following is incorrect regarding terminology?

• Grades of tolerances decides manufacture’s accuracy

• For any basic size there are 20 different shafts

• Line of zero deviation is known as zero line

• Tolerance has no sign

What is the actual deviation?

• Algebraic sum between actual size and corresponding basic size

• Algebraic difference between actual and corresponding basic size

• Average of actual and basic size

• Algebraic difference between upper and lower deviation

What is the condition for a positive upper deviation?

• Maximum limit of size > basic size

• Maximum limit of size is < basic size

• Minimum limit of size > basic size

• Maximum limit of size < basic size

What does ES represent in terminology as per IS: 919?

• Lower deviation of hole

• Upper deviation of shaft

• Lower deviation of shaft

• Upper deviation of hole

Why tolerances are given to the parts?

• Because it’s impossible to make perfect settings

• To reduce weight of the component

• To reduce cost of the assembly

• To reduce amount of material used

What is bilateral tolerance?

• Total tolerance is in 1 direction only

• Total tolerance is in both the directions

• May or may not be in one direction

• Tolerance provided all over the component body

Which type of tolerance provided in drilling mostly?

• Bilateral

• Unilateral

• Trilateral

• Compound

Which of the following is incorrect about tolerances?

• a) Too loose tolerance results in less cost

• b) Tolerance is a compromise between accuracy and ability

• c) Too tight tolerance may result in excessive cost

• d) Fit between mating components is decided by functional requirements

Which of the following option is true for given statements?

Statement 1: Bilateral tolerances are used in mass production techniques.

Statement 2: The basic size should be equal to upper and lower limits.

• a) T, T

• b) F, F

• c) T, F

• d) F, T