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CNC Machinery

Module 4: CNC Programming "Turning"

PREPARED BY

IAT Curriculum Unit

August 2009

© Institute of Applied Technology, 2009

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Module Objectives:

1. Identify the different parts that compose the program.

2. Utilize both preparatory functions (G-codes) and miscellaneous functions (M-codes).

3. Demonstrate the ability to write a program to manufacture a simple

workpiece using the MTS simulator.

4. Use some canned cycles in turning supported by the (SINUMERIK 840D) controller.

5. Utilize subprograms programs.

6. Verify the program graphically on the computer.

Module Contents

Topic Page No.

1 Structure of NC-program 4

2 Preparatory, additional and switching functions 5

3 How to write an NC program 7

4 Practical Tasks 12

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1. . Structure of an NC Program:

The NC program consists of a series of commands with which the CNC

machine tool is instructed to manufacture a certain work part. Fig. 4.1

1.1 Program beginning: it consists of a character (%) which informs the

controller that an NC Program will follow. Everything stands before

this character is ignored by the controller.

The first line in the NC Program contains the program name.

1.2 Program core: it consists of a sequence of blocks (Lines). Each block

contains the technical and geometric information that the controller

requires for the correspondent machining step. It starts always with

the block Number (N) e.g. N10, then the instructions or commands

follow.

1.3 Program end: it consists of one block having one command which is

M30.

Fig. 4.1 Structure of an NC Program

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2.Preparatory, additional and switching functions:

Four groups of instructions can be differentiated:

2.1 G-functions:

G functions are codes determine the geometric part of the NC

program. Some important G-Codes in the table below:

Function Description

G00 Rapid positioning; the tool will move to the target

point in rapid speed

G01 Feed rate positioning; the tool will move to the

target point according the feed rate speed

G02 Arc clockwise

G03 Arc counter clockwise

G04 Dwell; the tool will hold in place for a specific

amount of time, and then continues; e.g. G04 X5,

the tool will wait for 5 seconds.

G20 Inch units

G21 Metric units

G54 Work piece coordinate setting

G90 Absolute positioning; the tool will move to the

target point according to absolute dimensions.

G91 Incremental positioning; the tool will move to the

target point according to incremental dimensions.

G92 Max. Spindle speed limit.

G94 Feed rate (F) in mm/min., mainly for milling

G95 Feed rate (F) in mm/rev., mainly for turning

G96 Constant Cutting Speed

G97 Cancel Constant Cutting Speed

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2.2 Coordinates (X, Y & Z): they are used in a block to locate the target

point where the tool should go. In turning machines, tools follow 2

axes only, X & Z.

2.3 Additional and switching functions:


F Feed rate

S Speed

T Tool position

M3 Spindle rotation clockwise

M4 Spindle rotation counter clockwise

M5 Spindle stop

M6 Tool change

M7 Flood coolant #1 ON

M8 Flood coolant #2 ON

M9 Coolant OFF

M17 Subprogram end

M30 Program end

TRANS Zero point Shift

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2.4 Cycles:

A cycle allows performing a complete machining operation by specifying

just one code.

Cycle Description

Cycle 81 Drilling; to make a hole in one phase.

Cycle 83 Deep Drilling (Pecking); to make a deep hole,

which requires introducing the tool with several

phases.(Chip-breaking and chip removal)

Cycle 93 Recessing; to make an internal or external groove.

Cycle 95 Canned cycle (roughing and finishing cycle); to

cut the material following a pre-set contour using a

subprogram.

Cycle 97 Tapping; to make an internal or external thread.

3. How to write an NC program:

The program beginning consists of a character or a command (ex. %) which informs the CNC-control that a NC-program will follow. The first line in the NC program contains the program name (ex. TP0147). The NC-program names can contain alphanumerical (containing letters and numbers) or numerical characters. For most CNC-controls, 2-6 digit character sequences are used for identification. An NC-program consists of order sequence of blocks. They contain the geometric and technical information that the CNC-control requires for each machining step. Everything stands before the character % for commenting the program is ignored by the control. Program end M30 The program end is commanded with M30. Important note Everything that stands before the character % for commenting the program is ignored by the control. Comments are also allowed within the program, these must be set in brackets.

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Example 1:

Rapid traverse in absolute

dimensioning.

N30 G90

N40 G00 X30 Z5

The tool will move to the target

point with rapid speed, following

the absolute dimensioning system

is shown in Fig. 4.2.

Example 2:

Rapid traverse in incremental

dimensioning.

N70 G91

N80 G00 X-12.5 Z-35

The tool will move to the target

point with rapid speed, following

the incremental dimensioning

system shown in Fig. 4.3.

Fig. 4.2: Rapid Traverse in absolute dimensioning.

Fig. 4.3: Rapid traverse in incremental

dimensioning.

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Example 3:

Feed rate traverse in absolute

dimensioning.

N120 G90

N130 G01 X140 Z-90

The tool will move in linear motion

to the target point with feed rate

speed, following the absolute

dimensioning system as illustrated

in Fig. 4.4.

Example 4:

Feed rate traverse in incremental

dimensioning.

N50 G91

N60 G01 X20 Z-60

The tool will move in linear motion

to the target point with feed rate

speed, following the incremental

dimensioning system as illustrated

in Fig. 4.5.

Fig. 4.4: Feed rate traverse in absolute dimensioning.

Fig. 4.5: Feed rate traverse in incremental dimensioning.

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Arcs clockwise and counter

clockwise.

When an arc is to be machined, the

interpolation parameters I, J & K

must be specified. These

parameters are used to define the

center of a circle for circular

movements as explained by Fig.

4.6.

• "I" is the distance between

the starting position and the

circle center in the X-

direction.

• "J" is the distance between


circle center in the Y-

direction.

• "K" is the distance between


circle center in the Z-

direction.

Since in turning there is no Y-axis,

then J is always zero and no need

to mention it in the block;

Fig. 4.6: I, and K parameters.

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Example 5:

Programming using G02 for

clockwise Arc. See Fig. 4.7

N50 G01 X80 Z-40

N60 G02 X140 Z-106 I+45 K-20

Example 6:

Programming using G03 for

Counterclockwise Arc. Refer to Fig.

4.8

N50 G01 X80 Z-50

N60 G03 X140 Z-80 I-15 K-45

Fig. 4.7: Programming using G02.

Fig. 4.8: Programming using G03.

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Practical Tasks

Practical Task (1)

Title: Facing

Create an NC program making 1 mm facing. The workpiece shown in the

drawing below is the finished part.

Parameters:

o Chuck type: outside.

o Chucking depth: 15 mm

o Material: Aluminum Almg1

o Zero point: right workpiece side

o Tool: Left Corner Tool, CL-SCLCL – 2020 L 1208 ISO30

o Max. spindle speed limit: 2000 RPM

o Constant cutting speed: 200 m/min

o Feed rate: 0.2 mm/rev.

o Spindle rotation: counter clockwise

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*Hints:

1-To create an NC program, use the following procedure:

a. Setup form (tools) using setup mode; described in module 3.

b. Setup sheet using setup dialog; described in module 3.

c. Main program using editor.

2-While programming in “editor” you can always use the function

“renumber” to reorganize the blocks numbers.

3-You can use “shift + insert” to insert a new line above.

Solution:

N10 G54

N15 G92 S2000

N20 T1 D1 M6

N25 G96 S200 F0.2 M4

N30 G0 X43 Z0

N35 G1 X-2

N40 G1 Z2

N45 G0 X150 Z150

N50 M30

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Practical Task (2)

Title: Turning

Using the same tool used in practical task (1), create an NC Program to

produce the finished workpiece shown in the drawing below. It is needed to

make a 1 mm facing operation prior to parallel turning; all dimensions are

in mm.

Parameters:




o Zero point: right workpiece side

o Tool: Left Corner Tool, CL-SCLCL – 2020 L 1208 ISO30


o Constant cutting speed: 200 m/min.



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*Hint:

If the tool is moving along one axis, no need to mention the

coordinate on the second axis.

Possible solution:

N10 G54

N15 G92 S2000

N20 T1 D1 M6

N25 G96 S200 F0.3 M4

N30 G0 X42 Z0

N35 G1 X-2

N40 G1 Z2

N45 G0 X45 Z0

N50 G1 X38 Z0

N55 G1 X38 Z-40

N60 G1 X40 Z-40

N65 G0 X40 Z0

N70 G1 X36 Z0

N75 G1 X36 Z-40

N80 G1 X38 Z-40

N85 G0 X38 Z0

N90 G1 X34 Z0

N95 G1 X34 Z-40

N100 G1 X36 Z-40

N105 G0 X36 Z0

N110 G1 X32 Z0

N115 G1 X32 Z-40

N120 G1 X34 Z-40

N125 G0 X34 Z0

N150 G1 X30 Z0

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N155 G1 X30 Z-40

N240 G1 X31 Z-40

N245 G0 X31 Z0

N250 G0 X150 Z150

N255 M30

Practical Task (3)

Title: Turning (using cycle 95)

Create an NC Program to produce the finished workpiece shown in the

drawing below using cycle 95. It is needed to make a 1 mm facing

operation prior to taper turning; all dimensions are in mm.

Parameters:




o Zero point: right work part side

o Tools:

Pos#1: Left Corner Tool, CL-SCLCL – 2020 L 1208

Pos#2: Left Corner Tool, CL-SVJCL – 2020 L 1604


o Constant cutting speed: 200 m/min

o Feed rate: 0.3 mm/rev


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Possible solution:

1-Subprogram (L1205):

Use the editor to write the following subprogram.

N20 G1 X40 Z0

N25 G1 X20 Z-40

N25 G1 X40 Z-40

N30 G1 X42 Z-40

N30 M17

Save the subprogram under the name L1205.

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2-Main program:

N10 G54

N15 G92 S2000

N20 T1 D1 M6

N25 G96 S200 F0.3 M4

N30 G0 X42 Z0

N35 G1 X-2

N40 G1 Z2

N45 G0 X42 Z2

N50 G0 X150 Z150

N55 T2 D1 M6

N60 G0 X42 Z2

N65 CYCLE95 ("L1205",2,0,0,0,0.2,0.1,0.1,1)

N70 G0 X150 Z150

N80 M30

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Practical Task (4)

Title: Recessing (using Cycle 93)

Create an NC Program to produce the finished work part shown in the

drawing below. It is needed to make 1 mm facing operation and using cycle

95 for parallel turning. All dimensions are in mm. All chamfers are 1mm x

45°. (Use absolute dimensioning).

Parameters:


o Chucking depth: 15mm



o Tools:


Pos#2: Recessing Tool, ER-SGTFL – 1212 L 1.85

o Max.spindle speed limit: 2000 RPM.

o Constant cutting speed: 200 m/min. for parallel turning and 125

for recessing.

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o Feed rate: 0.3 mm/rev. for parallel turning and 0.08 mm/rev.

for recessing.


*Hint:

You can use the “start-tag” / “end-tag” commands in “editor”

to copy/paste similar programs already done.

Possible solution:

1.Subprogram:

Use the editor to write the following subprogram.

N10 G1 X30 Z1

N15 G1 X30 Z0

N75 G1 X30 Z-60

N80 G1 X42 Z-60

N65 M17

Save the subprogram under the name L89.

2.Main program:

N10 G54

N15 G92 S2000

N20 T1 D1 M6

N25 G96 S200 F0.3 M4

N30 G0 X42 Z0

N35 G1 X-2

N40 G1 Z2

N45 G0 X42 Z2

N50 G1 X41 Z2

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CYCLE95 ("L89",2,0.2,0.2,0.2,0.2,0.1,0.1,3)

N360 G1 X42 Z-39

N250 G0 X150 Z150

N255 T2 D1 M6

N260 G96 S125 F0.08 M4

N265 G0 X32 Z-10

N270 G1 X30 Z-10

N280 CYCLE93 (30,-10,7.5,2,0,0,0,-1,-1,0,0,0.2,0.3,1.5,1,5)

N285 G0 X32 Z-27.5

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N290 G1 X30 Z-27.5

N295 CYCLE93 (30,-27.5,5,5,0,0,0,-1,-1,0,0,0.2,0.3,1.5,1,5)

N300 G1 X32 Z-42.5

N305 G1 X30 Z-42.5

N310 CYCLE93 (30,-42.5,7.5,2,0,0,0,-1,-1,0,0,0.2,0.3,1.5,1,5)

N315 G0 X150 Z150

N320 M30

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Practical task (5)

Title: Threading (using cycle 97)

Create an NC Program to produce the finished work part shown in the

drawing below. It is needed to make 1 mm facing operation prior to parallel

turning. All dimensions are in mm.

Parameters:


o Chucking depth: 15mm



o Tools:


Pos#2: Left Threading Tool, TL-LHTR –2020 R 60 2.5


o Constant cutting speed: 200 m/min. for parallel turning

o Spindle Speed for threading: 800 RPM


o Spindle rotation: counter clockwise for parallel turning and

clockwise for threading

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Possible solution:

1-Subprogram (L90): N10 G1 X20 Z2 N15 G1 X20 Z0 N75 G1 X20 Z-40 N80 G1 X40 Z-40 N55 M17 2-Main program: N10 G54

N15 G92 S2000

N20 T1 D1 M6

N25 G96 S200 F0.3 M4

N30 G0 X42 Z0

N35 G1 X-2

N40 G1 Z2

N45 G0 X41 Z2

N50 CYCLE95 ("L90",2,0.2,0.25,0,0.1,0.15,0.1,1)

N50 G0 X150 Z150

N250 T2 D1 M6

N255 M5

N260 G97 S800 F0.3 M4

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N265 CYCLE97 (2.5,,0,-35,20,20,10,0,1.25,0.02,29,0,30,4,3,1)

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((The following are the tables and information required to fill the

parameters of cycle 97))

IANG:

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N270 G1 X70 Z0

N275 G0 X150 Z150

N270 M30

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Practical task (6)

Title: CNC Turning Project.

Using the MTS Simulation software, create an NC Program in order to

manufacture the mechanical shaft shown in the technical drawing below.

1. Technical Drawing Overall diameter = 60mm; All chamfers are 1 x 45°

2. Machining Steps

a. Facing

b. Parallel Turning

c. Recessing

d. Threading

e. Center Drilling

f. Drilling

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Hints:

• It is up to the programmer to choose the suitable setup

parameters according to the material and the dimensions

of the finished work part.

• Direction of rotation is related to the tool in use.

3. Programming Steps

a-Tools Preparation:

i.Tool in position 1 – Left Corner Tool CL-SCLCL – 2020 L 1208 ISO30

ii.Tool in position 5 – Recessing Tool

ER-SGTFL – 2012 L 02.00-0 ISO30

iii.Tool in position 6 – Left Threading Tool TL-LHTR – 2020 R 60 3.5 ISO30

iv.Tool in position 7 – Spotting Drill DR-15.00 034 L HSS ISO30

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v.Tool in position 9 – Twist Drill DR-15.00 067 L HSS ISO30

b- Subprogram (L150):

N10 G1 X26 Z2

N15 G1 X30 Z-1

N20 G1 X30 Z-20

N25 G1 X33 Z-20

N30 G1 X35 Z-21

N35 G1 X35 Z-30

N40 G1 X38 Z-30

N45 G1 X40 Z-31

N50 G1 X40 Z-60

N55 G1 X41 Z-60

N60 G3 X45 Z-62 I0 K-2

N65 G1 X45 Z-70

N70 G1 X60 Z-100

N75 G1 X60 Z-110

N80 G1 X65 Z-110

N85 M17

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C- Main Programming

i- Machine Setup: in order to set the machine, a setup sheet is created,

where all the following has to be mentioned:

1. Chucking device

2. Chuck’s dimensions

3. Chucking depth

4. Blank part’s dimensions

5. Material

6. Zero point location

7. Tool’s set

1-Selecting the chuck type

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2- Defining workpart dimensions, material and zero point

3- Selecting tool equipment

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The following is the automatically generated Setup Sheet: {) {{ 15.04.2008 14:47 { { CONFIGURATION { MACHINE MTS01 TM-016_-R1_-060x0646x0920 { CONTROL SINUMERIK 840DT { { PART { CYLINDER D+060.000 L+142.000 { MATERIAL "N\Aluminium\AlMg1" { DENSITY 002.70 { { MAIN SPINDLE WITH WORKPART { CHUCK "Chuck Turning\Jaw chuck\KFD-HS 130" { STEP JAW "Jaw\Step jaw\HM-110_130-02.003" { CHUCKING DEPTH E25.000 {{ Right side of the part: Z+235.000 { { TOOLS { T01 "DIN69880 V 30\Left corner tool\CL-SCLCL-2020 L 1208 ISO30" { T02 EMPTY { T03 EMPTY { T04 EMPTY { T05 "DIN69880 V 30\Recessing tool\ER-SGTFL-2012 L 02.0-0 ISO30" { T06 "DIN69880 V 30\Left threading tool\TL-LHTR-2020 R 60 3.50 ISO30" { T07 "DIN69880 V 30\Spotting drill\DR-15.00 034 L HSS ISO30" { T08 EMPTY { T09 "DIN69880 V 30\Twist drill\DR-15.00 067 L HSS ISO30" { T10 EMPTY { T11 EMPTY { T12 EMPTY { T13 EMPTY { T14 EMPTY { T15 EMPTY { T16 EMPTY { { TOOL COMPENSATION { D01 T01 Q3 R000.800 X+070.000 Z+045.000 G000.000 E005.005 I-000.800 K-000.800 A+004.375 L011.855 N01 { D02 T02 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D03 T03 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000

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I+000.000 K+000.000 A+000.000 L000.000 N01 { D04 T04 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D05 T05 Q3 R000.200 X+060.000 Z+041.000 G002.000 E000.000 I-000.200 K-000.200 A+000.000 L012.000 N01 { D06 T06 Q8 R000.505 X+070.000 Z+042.699 G000.000 E000.000 I-000.505 K+000.000 A+000.000 L000.000 N01 { D07 T07 Q7 R000.000 X+000.000 Z+106.000 G015.000 E045.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D08 T08 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D09 T09 Q7 R000.000 X+000.000 Z+140.000 G015.000 E059.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D10 T10 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D11 T11 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D12 T12 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D13 T13 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D14 T14 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D15 T15 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { D16 T16 Q0 R000.000 X+000.000 Z+000.000 G000.000 E000.000 I+000.000 K+000.000 A+000.000 L000.000 N01 { { WORKPART ZEROPOINTS {{ Right side of the part: Z+235.000 { G54 X000.000 Z+233.000 { {) ii- Main Program: N10 G54

N15 G92 S2000

N20 G00 X150 Z150

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a-Facing

N25 T1D1 M6

N30 G96 S200 F0.2 M4

N35 G00 X65 Z0

N40 G01 X-2

N45 G01 Z2

b-Parallel Turning

N50 G00 X26 Z5

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N55 CYCLE95 ("L150",2,0,0,,0.2,0.1,0.1,1)

N60 G00 X150 Z150 c- Recessing

N65 T5 D1 M6

N70 G96 S125 F0.08 M4

N75 G00 X45 Z-50

N80 CYCLE93 (40,-50,5,2.5,0,0,0,-1,-1,0,0,0.2,0.3,0.5,1,5)

N85 G00 X45 Z-35

N90 CYCLE93 (40,-35,5,2.5,0,0,0,-1,-1,0,0,0.2,0.3,0.5,1,5)

N95 G00 X150 Z150

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d- Threading

N100 T6 D1 M6

N110 M5

N115 G97 S1000 M3

N120 G00 X35 Z10

N125 CYCLE97 (,30,0,-15,30,30,8,0,2.15,0.02,29,0,15,3,3,1)

N130 G00 X150 Z150

e- Center Drilling

N135 T7 D1 M6

N140 M5

N145 G96 S100 M4

N150 G00 X0 Z5

N155 G01 Z-5

N160 G01 Z5

N165 G00 X150 Z150

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f- Drilling

N170 T9 D1 M6

N175 G96 S1000 F0.2 M4

N180 G00 X0 Z5

N185 G01 Z-15

N190 G01 Z5

N230 G00 X150 Z150

N235 M30

Finished Part

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Student's Notes:

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Work Sheet

Part (A):

1.Write (T) for true and (F) for false following statements:

1. The character (%) informs the controller that an NC

program will follow.

2. Everything before (%) is processed by the controller.

3. The first line in an NC program is the Number (N)

4. The first line in a block is the program’s name

5. An NC program is a sequence of blocks

2. Complete the following sentences:

1- The ____________________ consists of a series of commands with which the CNC machine tool is instructed to manufacture a certain work part. 2- ___________________ is the first word in a block. 3- The _____________________ are codes determine the geometric

part of the NC-program.

4- A ___________________ allows performing a complete machining

operation by specifying just one code.

5- Everything stands before ___________ is ignored by the control.

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Part (B):

1. Complete the following tables:


F

S

Tool position

M3

M4

M5

Tool change

Coolant OFF

M30


G00

G01

G02

G03

G90

Incremental positioning

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Part (C):

a - Write a block to move the cutting tool from starting point to target point using feed rate positioning and incremental mode.

N20 ………………………………………………

N30 ……………………………………………..

. B - Write a command to move the tool tip from starting point to target point Using rapid positioning and absolute mode.

N20 ………………………………………………

N30 ……………………………………………..

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C - Complete the following NC program blocks using absolute dimensioning mode.

N20 ………………………………………………

N30 …………………………………………….. D - Complete the following NC program blocks using absolute dimensioning mode.

N20 …………………………………………………

N30 ………………………………………………..

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Part (D): 1. What is the G code used to select the metric units of measurement?

a. G21 b. G20 c. G96 d. G19

2. What is the M code used to switch on the coolant?

a. M03 b. M08 c. M04 d. M09

3. What is the M code used to end a subprogram? a. M17 b. M05 c. M30 d. M02

4. In TOPTURN editor, "shift+insert" is used to:

a. Delete a line

b. Create a line below

c. Create a line above

d. None of the above

5. While programming in MTS "editor" the function ___________________

is used to reorganize the blocks numbers.

a. Dialog program

b. Renumber

c. Link programs

d. WOP

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6. Match each code with its function. Write the corresponding

number in the space provided.

1 G96 _____ Feed in mm/min.

2 M07 ______ Constant cutting speed

3 G94 ______ Feed in mm/rev.

4 G20 ______ Coolant ON

5 G95 ______ Input inch units

7. Complete the following table:

Cycle Description

Tapping (threading) cycle

Roughing and finishing cycle

Deep drilling cycle

Recessing cycle

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Part (E) 1. Write a program to do facing by cutting only 1 mm (at Z0) for the work part shown in the figure. Given that:

Work part diameter D= 50 mm Tool = T03 Constant cutting Speed = 300 m/min in

counterclockwise direction. Max. spindle speed = 2000 RPM Feed = 0.2 mm/rev

2. Write a short program to produce the shape shown below:

Needed: To do 1mm facing (Z=-1) then straight turning according to the drawing above, using one tool. Given: - Blank diameter 54 mm

Speed limit: 2000 RPM Constant speed: 200 m/min in counterclockwise direction. Feed Rate: 0.02 mm/min.

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N15 G54

N20 _________________________

N30 _________________________

N40 _________________________

N50 _________________________

N55 _________________________

N60 _________________________

N70 _________________________

N80 _________________________

N90 _________________________

N100 ________________________

N110 ________________________

N120 ________________________

2. Read the following NC-program carefully, then answer the questions below: N310 G54

N315 G92 S3000

N320 T1 D1

N325 G96 S200 F0.2 M4

N330 G0 X42 Z0

N335 G1 X-2

N340 G1 Z2

N345 G0 X100 Z100

N350 T2 D1

N355 G0 X20 Z5

N360 CYCLE95 ("L142",2,0,0,,0.2,0.15,0.1,1)

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N365 G0 X70 Z70

N370 T5 D1

N375 G0 X21 Z2

N380 M5

N385 M3

N390 CYCLE97 (,20,0,-35,20,20,10,0,1.53,,29,0,30,4,3,1)

N395 G0 X100 Z100

N400 M30

1. From the program shown above, the maximum spindle speed

is__________

A.2000 RPM

B.1500 RPM

C.3000 RPM

. D.2500RPM

2. G00 X100 Z100 Means

A. tool changing point

B. zero point shift

C. cutting speed and feed rate rotation direction for finishing

. D. constant spindle speed and rotation direction

3. In the block N360 CYCLE95 ("L142",2,0,0,,0.2,0.15,0.1,1), L142 means

A. main program

B. subprogram

C. depth of cutting

. D. tool number

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4. Cycle 97 is used to make

A. roughing

B. recessing

C. threading

D. finishing

5. Cycle 95 could be used for

A. roughing

B. recessing

C. threading

D. taper undercut

6. M30 means

A. program end

B. subprogram end

C. program stop

D. none of the above

7. T5 D1 block is used to:

A. switch the spindle on

B. call tool number 5

C. compensate tool 1

D. switch the spindle off

8. The block G96 S200 F0.2 M4 stands for:

A. speed limit max 200 rpm

B. constant cutting speed of 200 m/min

C. cutting speed limit of 2000 rpm

D. speed limit min 2000 rpm

9. The G code which is used to select the work part zero point is

A. G21

B. G45

C. G54

D. G50

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10. “G01 X=-2” in a facing operation is used to:

A. Change tool number 2

B. Move in rapid traverse to X=-2

C. Remove the pin at the end of the part caused by the tool tip

D. Create an arc counter clockwise

Part (F):

a) Study the following drawing and then answer the questions below

if the recessing starts from the right side.

1. Complete the missing data in the following table.

Start point in X Start point in Z Width of recess Depth

2. For the second recess complete the missing data in the following table Start point in X Start point in Z Width of recess Depth

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b) Give the listed parameters for the grooving cycle shown in the figure below:

1. Start Point in X: 70 mm

2. Start Point in Z: 60 mm

3. Groove Width: __ mm

4. Groove Depth: __ mm

5. Angle contour – longitudinal axis: __ °

6. Flank Angle Start Point: __ °

7. Flank Angle Opposite: __ °

8. Radius / Chamfer outside start point: __ mm

9. Radius / Chamfer outside opposite: __ mm

10. Chamfer inside start point: __ mm

11. Chamfer inside opposite: __ mm

References: 1. Turning Programming Manual – MTS 2. CNC technology – NCADU

cnc machinery - maysaa nazar · pdf fileatm 313 – cnc module 4: cnc programming...

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