CNC

Question 1

a method for automating the control of machine tools through the use of software embedded in a microcomputer attached to the tool.

Answer 1

Computer numerical control (CNC)

Question 2

international standard language

Answer 2

G-code

Question 3

were built in the 1940s and 1950s by Prof. John T. Parson

Answer 3

NC machines

Question 4

a method of automatically operating a manufacturing machine based on a code of letters, numbers and special characters.

Answer 4

Numerical Control

Question 5

converts written instruction into a corresponding hole pattern.

Answer 5

Tape punch

Question 6

reads the hole pattern on the tape and converts the pattern to corresponding electrical signal code.

Answer 6

Tape reader

Question 7

receives the electrical signal code from the tape reader and subsequently causes the NC machine to respond.

Answer 7

Controller

Question 8

responds to programmed signals from the controller.

Answer 8

NC machine

Question 9

It is a NC machine with the added feature of an onboard computer. The onboard computer is often referred to as the Machine Control Unit (MCU).

Answer 9

Computer Numerical Control

Question 10

generates, stores and processes CNC programs.

Answer 10

Machine Control Unit

Question 11

responds to programmed signals from the MCU and manufacture the part

Answer 11

NC machine

Question 12

An alphanumeric character or punctuation marks

Answer 12

Programming Character

Question 13

A letter that describes the meaning of numerical value following the address

Answer 13

Addresses

Question 14

Composed of an address and a number

Answer 14

Word

Question 15

Is a complete line of information to a CNC machine.

Answer 15

Blocks

Question 16

Is a sequence of blocks that describe in detail the motions a CNC machine is to execute in order top manufacture a part. The MCU execute the program block by block.

Answer 16

Programs

Question 17

Different types of system control

Answer 17

Fanuc
Allen-Bradley
GE
Okuma
Bendix
Mazak
Others

Question 18

They cause the tool to move to a point on the part and execute an operation at that point only.

Answer 18

Point-to-point control movement

Question 19

They cause the tool to maintain continuous contact with the part as the tool cut contour shape.

Answer 19

Continuous path tool movement

Question 20

Is a mathematical method of approximating the true or exact position required to follow a pre-calculated path.

Answer 20

Interpolation

Question 21

send electrical signals to drive motor controllers and receives some form of electrical feedback from the motor controllers.

Answer 21

loop system

Question 22

utilizes stepping motors to create machine movements

Answer 22

open loop system

Question 23

Special motor called servos are used for executing machine movements in __________

Answer 23

Closed Loop System

Question 24

All ballscrews have some “slop” or _________ at assembly that causes errors when the screws reverses direction and the nuts lag behind.

Answer 24

Backlash

Question 25

The location of CNC tool at any time is controlled by a XYZ coordinates

Answer 25

Cartesian Coordinates

Question 26

executes machining operations by performing some form of sliding linear motion and rotary motion.

Answer 26

CNC equipment

Question 27

EIA RS-267A standard

Question 28

Right Hand Rule for Linear Motion

Question 29

locate each new tool position by measuring from the last tool position established. if one ____________ movement is in error, all subsequent movements will be incorrect.

Answer 29

Incremental Positioning

Question 30

is a machine tool used principally for shaping articles of metal (and sometimes wood or other materials) by causing the workpiece to be held and rotated by the lathe while a tool bit is advanced into the work causing the cutting action.

Answer 30

Lathe Machine

Question 31

– are large lathe and is usually floor mounted. It can handle more machining jobs

Answer 31

Engine Lathes

Question 32

are usually used in production or job shops for mass production and specialized parts.

Answer 32

Turret Lathes and Special Purpose Lathe

Question 33

is the foundation of the working parts of the lathe to another

Answer 33

bed

Question 34

is located on the operator’s left end of the lathe bed. It contains the main spindle and oil reservoir and the gearing mechanism

Answer 34

headstock

Question 35

mounted on bearings in the headstock and is hardened and specially ground to fit different lathe holding devices.

Answer 35

main spindle

Question 36

may be inserted into the spindle.

Answer 36

Centers, collets, drill chucks, tapered shank drills  and reamers

Question 37

may be screwed onto the spindle or clamped onto the spindle nose.

Answer 37

Chucks, drive plates, and faceplates

Question 38

located on the opposite end of the lathe from the headstock

Answer 38

tailstock

Question 39

includes the apron, saddle, compound rest, cross slide, tool post, and the cutting tool.

Answer 39

carriage

Question 40

carries the cross slide and the compound rest.

Answer 40

saddle

Question 41

mounted on the cross slide and can be swiveled and clamped at any angle in a horizontal plane.

Answer 41

compound rest

Question 42

are secured in the tool post which is mounted directly to the compound rest

Answer 42

cutting tool and tool holder

Question 43

mounted on the dovetail ways on the top of the saddle and is moved back and forth at 90° to the axis

Answer 43

cross slide

Question 44

contains the gears and feed clutches which transmit motion from the feed rod or lead screw to the carriage and cross slide

Answer 44

apron

Question 45

has a radius ground onto the nose of the tool bit that is smaller than the radius for a finishing

Answer 45

roughing tool

Question 46

is shaped to be fed from right to left.

Answer 46

right-hand turning tool bit

Question 47

is the opposite of the right-hand designed to cut when fed from left to right

Answer 47

left-hand turning tool bit

Question 48

very versatile and can be used to turn in either direction for roughing and finishing cuts.

Answer 48

round-nose turning tool bit

Question 49

is machining the ends and shoulders of a piece of stock smooth.

Answer 49

Facing

Question 50

sometimes called cylindrical turning, is the process of reducing the work diameter to a specific dimension

Answer 50

Straight Turning

Question 51

are machined to add strength for parts that are to be fitted together, make a corner, or improve the appearance of a part.

Answer 51

Shoulders

Question 52

to add to the general appearance of the work. Common types of corners are chamfered, rounded, and square

Answer 52

Corners

Question 53

Undercuts are the reductions in diameter machined onto the center portion of workplaces

Answer 53

Undercuts

Question 54

(or necking) is the process of turning a groove or furrow on a cylinder, shaft, or workpiece.

Answer 54

Grooving

Question 55

the process of machining radii and these irregular shapes.

Answer 55

Form turning

Question 56

When the diameter of a piece changes uniformly from one end to the other, the piece is said to be tapered.

Answer 56

TAPER TURNING

Question 57

is a uniform helical groove cut inside of a cylindrical workpiece, or on the outside of a tube or shaft.

Answer 57

SCREW THREAD CUTTING (thread)

Question 58

is a process of impressing a diamond shaped or straight line pattern into the surface of a workpiece by using The diamond

Answer 58

Knurling

Question 59

is the enlarging and truing of a hole by removing material from internal surfaces with a single-point cutter bit

Answer 59

Boring

Question 60

sometimes called channeling or cambering, is the process of cutting a groove inside of a drilled, bored, or reamed hole.

Answer 60

RECESSING

Question 61

The address code G90 in a program

Answer 61

absolute mode.

Question 62

The code G91

Answer 62

incremental mode.

Question 63

The most common codes used when programming CNC machines tools are

Answer 63

G-codes (preparatory functions), and M codes (miscellaneous functions).

Question 64

sometimes called cycle codes because they refer to some action occurring on the X, Y, and/or Z axis of a machine tool

Answer 64

G-codes

Question 65

, containing codes G00, G01, G02, G03,

Answer 65

Group 1

Question 66

includes either absolute or incremental programming

Answer 66

Group 3

Question 67

deals with canned cycles.

Answer 67

Group 09

Question 68

The _____ ______ ______ move the axes at a controlled feedrate.

Answer 68

G01, G02, and G03 codes

Question 69

codes are used to either turn ON or OFF different functions which control certain machine tool operations, figure below.

Answer 69

M or miscellaneous codes

Question 70

M-codes are not grouped into categories, although several codes may control the same type of operations such as

Answer 70

M03 turns the spindle on clockwise * M04 turns the spindle on counterclockwise * M05 turns the spindle off

Question 71

machine tool that removes metal as the work is fed against a rotating multipoint cutter.

Answer 71

milling machine

Question 72

rotates at high speed and it removes metal at a very fast rate with the help of multiple cutting edges.

Answer 72

milling cutter

Question 73

Once or more number of cutters can be mounted simultaneously on the

Answer 73

arbor

Question 74

Classification of Milling Machine

Answer 74

According to the nature of purpose of use According to the orientation of the spindle According to configuration and motion of the work holding table/bed According to automation and production rate

Question 75

Machining flat surfaces which are at right angles to the axis of the cutter,

Answer 75

Face milling.

Question 76

Machining flat surfaces which are at an inclination to the axis of the cutter.

Answer 76

Angular milling

Question 77

Machining surfaces having an irregular outline

Answer 77

Form milling

Question 78

Different Milling Operations

Answer 78

Surface, slot, dovetail, T-slot, Form, Straddle, Angular, Boring, Drilling

Question 79

Workpiece fed with Milling cutter

Answer 79

Climb Milling

Question 80

Workpiece fed against Milling Cutter

Answer 80

Conventional Milling