Factor

Process

parameters

Sum of

squares

Degrees of

freedom

Mean sum

of squares

F-test

A

Rotational speed

244.401

2

122.20

16.21

B

Welding speed

179.994

2

89.99

11.94

C

Axial load

35.555

2

17.77

2.36

Error

15.075

2

7.53

Total

475.025

8