Exam

Question 1

What is meant by the surface finish and 2 ways it should be specified on engineering drawings

Answer 1

Surface finish or roughness describes the nature of the surface that is produced by different manufacturing processes

Question 2

Use sketches to show how the surface finish is measured and define 2 important parameters used to quantify finish

Answer 2

Stylus with a diamond tip and small radius is traversed across the surface

Trace is shown on a computer with print out

(Show typical Graph)

Question 3

Use a graph to show how the nature of the surface finish depends on the manufacturing process adopted and discuss the cost implications.

Answer 3

Graph shows improving surface finsih takes longer + uses more operations this adds to cost.

Question 4

Describe three components where the surface finish plays an important part in the quality and performance of the product

Use sketches to illustrate your answer.

Answer 4

Engine Cylinder - is honed to provide crosshatch finish to provide valleys for oil retention (lubrication)

Hydraulic cylinder tube - smooth bore finish to extend seal life & prevent leaking

wheel bearing - ball on roller surface important for smooth running & long bearing life as well as noise reduction.