Manufacturing Engineering Multiple Choice Questions on “Computer Integrated Manufacturing”.
1. During the execution of a CNC part program block NO20 GO2 X45.0 Y25.0 R5.0 the type of tool motion will be
a) circular Interpolation – clockwise
b) circular Interpolation – counterclockwise
c) linear Interpolation
d) rapid feed
Answer: a
Clarification: Given:-NO20 GO2 X45.0 Y25.0 R5.0
Here term X45.0 Y25.0 R5.0 will produce circular motion because radius is consider in this term and GO2 will produce clockwise motion of the tool.
2. In an NC machining operation, the tool has to be moved from point (5, 4) to point (7, 2) along a circular path with centre at (5, 2). Before starting the operation, the tool is at (5, 4). The correct G and N codes for this motion are
a) N010GO3X7.0Y2.0I5.0J2.0
b) N010GO2X7.0Y2.0I5.0J2.0
c) N010GO1X7.0Y2.0I5.0J2.0
d) N010GOOX7.0Y2.0I5.0J2.0
Answer: b
Clarification: Given : Initial point (5, 4), Final point (7, 2), Centre (5, 4)
So, the G, N codes for this motion are N010GO2X7.0Y2.0 15.0J2.0
where, GO2 ” Clockwise circular interpolation
X7.0Y2.0 ” Final point
I5.0J2.0 ” Centre point.
3. The tool of an NC machine has to move along a circular arc from (5, 5) to (10, 10) while performing an operation. The centre of the arc is at (10, 5). Which one of the following NC tool path command performs the above mentioned operation?
a) N010 GO2 X10 Y10 X5 Y5 R5
b) N010 GO3 X10 Y10 X5 Y5 R5
c) N010 GO1 X5 Y5 X10 Y10 R5
d) N010 GO2 X5 Y5 X10 Y10 R5
Answer: a
Clarification: N010 “represent start the operation
GO2 “represent circular (clock wise) interpolation
X10Y10 “represent final coordinates
X5Y5 “represent starting coordinate
R5 “represent radius of the arc
So, NC tool path command is, N010 GO2 X10 Y10 X5 Y5 R5.
4. NC contouring is an example of
a) continuous path positioning
b) point-to-point positioning
c) absolute positioning
d) incremental positioning
Answer: a
Clarification: NC contouring is a continuous path positioning system. Its function is to synchronize the axes of motion to generate a predetermined path, generally a line or a circular arc.
5. Match the following:
NC code Definition P. M05 1. Absolute coordinate system Q. G01 2. Dwell R. G04 3. Spindle stop S. G09 4. Linear interpolation
a) P-2, Q-3, R-4, S-1
b) P-3, Q-4, R-1, S-2
c) P-3, Q-4, R-2, S-1
d) P-4, Q-3, R-2, S-1
Answer: c
Clarification: NC code Definition
P. M05 3. Spindle stop
Q. G01 4. Linear interpolation
R. G04 2. Dwell
S. G09 1. Absolute coordinate system
So, correct pairs are, P-3, Q-4, R-2, S-1.
6. In a CNC program block, N002 GO2 G91 X40 Z40……,GO2 and G91 refer to
a) circular interpolation in counterclockwise direction and incremental dimension
b) circular interpolation in counterclockwise direction and absolute dimension
c) circular interpolation in clockwise direction and incremental dimension
d) circular interpolation in clockwise direction and absolute dimension
Answer: c
Clarification: GO2 represent circular interpolation in clockwise direction.
G91 represent incremental dimension.
7. Numerical control ___________
a) applies only to milling machines
b) is a method for producing exact number of parts per hour
c) is a method for controlling by means of set of instructions
d) none of the mentioned