GD&T Surface Finish & Assembly Requirements 2

Question 1

On a drawing, the surface texture symbol with a horizontal bar beneath it indicates:

Accepted Answer

Material removal is prohibited

Answer

Material removal is required

Answer

Any manufacturing process is acceptable

Answer

The surface must be ground only

Question 2

Which Ra value represents the smoothest surface finish?

Accepted Answer

Ra 0.8 μm

Answer

Ra 6.3 μm

Answer

Ra 3.2 μm

Answer

Ra 1.6 μm

Question 3

A bearing bore drawing specifies a surface finish of Ra 0.4 μm and a flatness tolerance of 0.02 mm. What is the correct interpretation?

Accepted Answer

Both the surface finish and flatness must independently be met

Answer

Only the surface finish must be met

Answer

Only the flatness must be met

Answer

The tighter of the two controls the other

Question 4

In an assembly where a gasket seals between two flanges, which surface finish parameter is MOST critical for sealing performance?

Accepted Answer

Rp (maximum peak height)

Answer

Ra (average roughness)

Answer

Rz (average peak-to-valley height)

Answer

Rv (maximum valley depth)

Question 5

A profile of a surface tolerance applied all-around a part also controls:

Accepted Answer

Size, form, orientation, and location of that surface

Answer

Surface finish (Ra) automatically

Answer

Only the form of the surface

Answer

Only orientation relative to a datum

Question 6

When two mating surfaces must slide against each other under load, the designer should specify a surface finish that is:

Accepted Answer

Smooth enough to reduce wear but not so smooth as to cause adhesion

Answer

As rough as possible to increase friction

Answer

The same roughness on both mating surfaces always

Answer

Determined solely by the coating applied

Question 7

Which symbol in ASME Y14.5 indicates that a surface must be produced by a specific manufacturing process noted in the tail of the surface texture symbol?

Accepted Answer

Text written in the tail/extension of the symbol

Answer

A circle at the base of the check mark

Answer

A triangle added to the symbol

Answer

A wavy line through the symbol