GD&T GD&T Virtual Condition and Boundary Concepts 2

Question 1

What is resultant condition in GD&T?

Accepted Answer

The worst-case boundary generated by the collective effects of LMC size and the maximum geometric tolerance

Answer

Resultant condition is the worst-case boundary produced when a feature is at LMC and has the maximum allowed geometric error.

Question 2

For a pin (external feature) at LMC with a position tolerance, resultant condition equals:

Accepted Answer

LMC minus the geometric tolerance

Answer

For a pin, resultant condition = LMC − geometric tolerance, representing the smallest envelope the pin can produce.

Question 3

What does the inner boundary (IB) represent for a hole?

Accepted Answer

The smallest condition of the hole, equal to MMC minus the geometric tolerance

Answer

Inner boundary for a hole = MMC − geometric tolerance, the tightest restriction that must still clear a mating pin.

Question 4

What does the outer boundary (OB) represent for a pin?

Accepted Answer

The largest space the pin can occupy, equal to MMC plus the geometric tolerance

Answer

Outer boundary for a pin = MMC + geometric tolerance, the largest envelope any conforming pin can produce.

Question 5

A hole has MMC = 9.8 mm and a position tolerance of 0.2 mm at MMC. What is its virtual condition?

Accepted Answer

9.6 mm

Answer

Virtual condition for a hole = MMC − geometric tolerance = 9.8 − 0.2 = 9.6 mm.

(GD&T) Geometric Dimensioning and Tolerancing Certification Practice Test