CAD/CAM LAB REPORTFILE

SUBMITTED TO

Prof. Mohammed Suhaib(Dept. of Mechanical Engg.) Jamia Millia Islamia

Submitted by

Md.Azheruddin B.Tech (Mech.) 8th Semester 08-MES-37

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INDEXExp.NO Name of Experiment Date Signature

1 To study the open CIM setup of automation and CIM lab

23/01/12

2 To study the anatomy of Robotic Arm ER-5 And Er-7

06/02/12

3 To study and operate the CNC Lathe and CNC vertical milling machine

27/02/12

4 To study and operate the PLC controler and oval type conveyer belt

05/03/12

5 To write and run the CNC program for the Lathe Machine for the given drawing using CNC train simulator

9/04/12

6 To write and run the CNC program for the Milling Machine for the given drawing using CNC train simulator

9/04/12

EXPERIMENT NO-1Object:- To study the open CIM setup of automation and CIM lab.

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Equipments Required:- CNC machines, Robots, PlC’s, AS/RS, Computers, Conveyors etc.

Layout:-

Working of CIM:- Typically, a work piece, which is located at the ASRS, will be placed on the conveyor system by a gantry robot. The conveyor will transport the work piece to the CNC milling machine where another robot will pick up the work piece from the conveyor belt and place it in the machine. After the milling process, the robot will return it to the conveyor belt where another robot will pick up the work piece and place it in the CNC lathe machine. After the work piece has been machined, it will be transported by the conveyor belt to the assembly station for assembly and QC check. If the work piece is satisfactory, it will then be bar coded at the next station and transported to the ASRS for inventory purpose. The whole process is controlled by a Central Management Control Station (CMCS), which sends the exact instructions to the

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Pneumatic Pipeline

Stati

on 1

Air Compressor

Feeders

VSRS

ROBOT ER-V

PLC

MO

TOR

Stati

on 2

CNC Lathe

CNC Mill

ROBOT ER-VII

CONVEYORSTATION-1 PC CIM

Manager

STATION-2 PC Lathe PC

Mill PC

various stations for the work to be performed. The conveyor belt serves as a transport highway where the work piece will be loaded and sent on to its destination.

1. Automatic Storage and Retrieval System (ASRS)2. CNC Lathe Machine3. CNC Milling Machine4. Robots5. Assembly/Quality Control Station6. Closed Loop Conveyor System7. Barcode Scanning System8. Central Management Control Station (CMCS)

Theory:- Computer-integrated manufacturing (CIM) is the manufacturing  approach of using computers  to control the entire production process. The term "computer-integrated manufacturing" is both a method of manufacturing and the name of a computer-automated system in which individual engineering, production, marketing, and support functions of a manufacturing enterprise are organized. In a CIM system functional areas such as design, analysis, planning, purchasing, cost accounting, inventory control, and distribution are linked through the computer with factory floor functions such as materials handling and management, providing direct control and monitoring of all the operations. ELEMENTS OF CIM SYSTEM1. Marketing: The need for a product is identified by the marketing division. The specifications of the product, the projection of manufacturing quantities and the strategy for marketing the product are also decided by the marketing department. Marketing also works out the manufacturing costs to assess the economic viability of the product.

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2. Product Design: The design department of the company establishes the initial database for production of a proposed product. In a CIM system this is accomplished through activities such as geometric modeling and computer aided design while considering the product requirements and concepts generated by the creativity of the design engineer. The design process creates the database required to manufacture the part.

3. Planning: The planning department takes the database established by the design department and enriches it with production data and information to produce a plan for the production of the product. Planning involves several subsystems dealing with materials, facility, process, tools, manpower, capacity, scheduling, outsourcing, assembly, inspection, logistics etc.

4. Purchase: The purchase departments is responsible for placing the purchase orders and follow up, ensure quality in the production process of the vendor, receive the items, arrange for inspection and supply the items to the stores or arrange timely delivery depending on the production schedule for eventual supply to manufacture and assembly.

5. Manufacturing Engineering: Manufacturing Engineering is the activity of carrying out the production of the product, involving further enrichment of the database with performance data and information about the production equipment and processes. In CIM, this requires activities like CNC programming, simulation and computer aided scheduling of the production activity.

6. Factory Automation Hardware: Factory automation equipment further enriches the database with equipment and process data, resident either in the operator or the equipment to carry out the production process. In CIM system this consists of computer controlled process machinery such as CNC machine tools, flexible manufacturing systems (FMS), Computer controlled robots, material handling systems, computer controlled assembly systems etc.

7. Warehousing: Warehousing is the function involving storage and retrieval of raw materials, components, finished goods as well as shipment of items. In today’s complex outsourcing scenario and the need for just-in-time supply of components and subsystems, logistics and supply chain management assume great importance.

8. Finance: Finance deals with the resources pertaining to money. Planning of investment, working capital, and cash flow control, realization of receipts, accounting and allocation of funds are the major tasks of the finance departments.

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9. Information Management: Information Management is perhaps one of the crucial tasks in CIM. This involves master production scheduling, database management, communication, manufacturing systems integration and management information systems.

Advantages of CIMS:1. Increased machine utilization2. Reduced direct and indirect labor3. Reduce mfg. lead time4. Lower in process inventory5. Scheduling flexibility

QUESTION AND ANSWERSQ1. Name any 5 CAM softwares?Ans. CATIA, Dynavista, Edgecam, SolidCam, WorkNC, PowermillQ2. What are the various material handling systems?Ans. (i) AGV (ii) Robots (iii) AS/RSQ3. Name any 5 CAD softwares?Ans. AutoCAD, 3D-Max, Solid Works, Unigraphics, Maya, PRO-EQ4. Broadly CNC machining centers are classified into how many types?Ans. (i) Vertical axis machining centers (ii) Horizontal axis machining centersQ5. What is the function of Machine Control Unit (MCU)?Ans. CNC part program is executed by the MCU to achieve the final component design.

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EXPERIMENT NO-2Object: -To study the anatomy of Robotic Arm ER-5,ER-7

Equipments Required: - Scorbot ER-5,Scorbot ER-7 teach pendantSpecifications:-SCORBOT-ER V plus SpecificationsNumber of Axes 5 axes plus servo gripperAxis MovementAxis 1: Base rotationAxis 2: Shoulder rotationAxis 3: Elbow rotationAxis 4: Wrist pitchAxis 5: Wrist roll

310°+130° / –35°±130°±130°Unlimited (mechanically); ±570° (electrically)

Maximum Operating Radius 610mm (24.4")End Effectors DC servo gripper, with optical encoder,

parallel finger motion; Measurement of object’s size/gripping force by means of gripper sensor and software.

Maximum Gripper Opening 75 mm (3") without rubber pads65 mm (2.6") with rubber pads

Actuators 12VDC servo motorsMotor Capacity (axes 1–6) 15 oz. in Peak Torque (stall)

70 W Power for Peak TorqueGear Ratios Motors 1, 2, 3: 127.1:1

Motors 4, 5: 65.5:1Motor 6 (gripper) 19.5:1

Position Repeatability ±0.5 mm (0.02") at TCP (tip of gripperMaximum Path Velocity 600 mm/sec (23.6"/sec)Weight 11.5 kg (25 lb)

ER-5 robot

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SCORBOT-ER VII SpecificationsNumber of Axes 5 axes plus gripperAxis MovementAxis 1: Base rotationAxis 2: Shoulder rotationAxis 3: Elbow rotationAxis 4: Wrist pitchAxis 5: Wrist roll

250°; 310° user programmable170°225°180°360°

Maximum Operating Radius 690 (27.2") at flangeEnd Effectors options Pneumatic and DCServoActuators 12VDC servo motorsTransmission Harmonic drives; timing belts and pulleysPosition Repeatability ±0.2 mm (0.008")Weight 30 kg (66 lbs)Maximum Path Velocity 1000 mm/sec (39.4"/sec)Maximum Payload 2 kg (4.4 lb.), including gripperAmbient Operating Temperature 2°–40°C (36°–104°F)

Figure: SCORBOT-ER VII Robot Arm

Theory:-Types of Robots:-

1. Cartesian Coordinate Robot (also called linear robot) is an industrial robot whose threeprincipal axes of control are linear (i.e. they move in a straight line rather than rotate) and are atright angles to each other. Among other advantages, this mechanical arrangement simplifies theRobot control arm solution. Cartesian coordinate robots with the horizontal member supported at both ends are sometimes called Gantry robots. Used for pick and place work, application of sealant, assembly operations, handling machine tools and arc welding.

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2. Spherical Coordinate Robot is a robot with two rotary joints and one prismatic joint. Spherical robots have an arm which forms a spherical coordinate system. Used for handling at machine tools, spot welding, diecasting, fettling machines, gas welding and arc welding. It's a robot whose axes form a polar coordinate system.

3. Cylindrical Coordinate Robot has two linear axes and one rotary axis. The robot derives its name from the operating envelope.The Z axis is located inside the base, resulting in a compact end-of-arm design that allows the robot to "reach" into tight work envelopes without sacrificing speed or repeatability.Used for assembly operations, handling at machine tools, spot welding, and handling at diecasting machines.

4. Articulated Robot is a robot with rotary joints. Articulated robots can range from simple two-jointed structures to systems with 10 or more interacting joints. They are powered by a variety of means, including electric motors.Used for assembly operations, fettling machines, gas welding, arc welding and spray painting. It's a robot whose arm has at least three rotary joints.

5. SCARA Robot: SCARA stands for Selective Compliant Assembly Robot Arm or Selective Compliant Articulated Robot Arm. By virtue of the SCARA's parallel-axis joint layout, the arm is slightly compliant in the X-Y direction but rigid in the ‘Z’ direction, hence the term:Selective Compliant.The second attribute of the SCARA is the jointed two-link arm layout similar to our human arms, hence the often-used term, Articulated. SCARA's are generally faster and cleaner than comparable Cartesian systems.Used for pick and place work, application of sealant, assembly operations and handling machine tools.

Basic Components of a Robot:-

1.Manipulatorwhich is the robot’s arm, consists of segments jointed together with axes capable of motion in various directions allowing the robot to perform work.

2. End Effector which is a gripper tool, a special device, or fixture attached to the robot’s arm, actually performs the work.

3. Power supply provides and regulates the energy that is converted to motion by the robot actuator, and it may be electric, pneumatic, or hydraulic.

4. Controller initiates, terminates, and coordinates the motion of sequences of a robot. Also it accepts the necessary inputs to the robot and provides the outputs to interface with the outside world.

Teach Pendant: The teach pendant is an optional device.

The teach pendant (TP) is a hand-held terminal, used for controlling the robot andaxis connected to controller. The teach pendant is most practical for moving the axes, recording positions, sending the axes to recorded positions, and activating programs. Otherfunctions can also be executed fromthe teach pendant.The teach pendant has 30 functionkeys. Many of thecommand keys on the teach pendant are ACL commands.

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QUESTION AND ANSWERS

Q1. Which type of robot is also called as Gantry Robots?

Ans. Cartesian coordinate robots with the horizontal member supported at both ends are sometimes called Gantry robots.

Q2. What are the basic types of clamping mechanism used in grippers?

Ans. (i) Mechanical clamping (ii) Magnetic clamping (iii) Vacuum clamping

Q3. What is the workspace/ work envelope of a robot?

Ans. It is the maximum volume that a robot can reach mechanically.

Q4. What are the applications of SCARA Robot?

Ans.Used for pick and place work, application of sealant, assembly operations and handling machine tools.

Q5. What are the types of motion controls used in robots?

Ans. (i) Axis limit (ii) Contouring (iii) Point-to-Point(iv) Line tracking

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EXPERIMENT NO. 03

OBJECT: - To study and operate the CNC Lathe and CNC vertical milling machine.EQUIPMENT: - PLC controller, CNC Lathe and CNC vertical milling machine etc.SPECIFICATION:- Main Specification Of Vertical CNC milling nachine(DENFORD STAR MILL)Accuracy resolution 0.01mmMax. Drilling diameter 13mmMax.End- Milling diameter 16mmMax.Surface-Milling diameter 30mmspindle speed High speed：100~2500 r.p.m ±10%

low speed：100~1100 r.p.m ±10%Z Axis BallScrew 16mm dia×5 mm pitchX- Axis BallScrew 10mm dia×4 mm pitchY- Axis BallScrew 10mm dia×4 mm pitchCross Travel 90mmHead Travel 115 mmElectric Power 50/60Hz-1 Phase 220/240V 8A Spidle

Moter( LxWx H)overall dimension 875 × 800 × 800mmNet/gross weight 100kg

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Main Specification Of CNC Lath machine (DENFORD STARTURNER)positioning accuracy or resolution 0.01mmmax swing diameter over bed 140mmmax workpiece length 250mmmax turning diameter 70mmspindle speed(infinitely adjuested 0-2000rpmspindle hole diameter 10mmX-axis ballscrew 8 mm Ø2.5 mmZ-axis ballscrew 10mm Ø4 mmfeed rate X:1100mm/min，Z：1100mm/minDistance between centers 250mmElectrical power 1 phase 220/240 volts 6Amp spindle moterStepeer motors 200steps/rev dcnet/gross weight 70kgoverall dimension(LxWxH) 660 × 425 × 430mm

Working of vertical CNC milling MachineComputer Numerical Control (CNC) Milling is the most common form of CNC. CNC mills can perform the functions of drilling and often turning. CNC Mills are classified according to the number of axes that they possess. Axes are labeled as x and y for horizontal movement, and z for vertical movement, as shown in this view of a manual mill table. A standard manual light-duty mill (such as a Bridgeport™) is typically assumed to have four axes:

1. Table x.2. Table y.3. Table z.

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4. Milling Head z

High speed CNC Milling

The number of axes of a milling machine is a common subject of casual "shop talk" and is often interpreted in varying ways. We present here what we have seen typically presented by manufacturers. A five-axis CNC milling machine has an extra axis in the form of a horizontal pivot for the milling head, as shown below. This allows extra flexibility for machining with the end mill at an angle with respect to the table. A six-axis CNC milling machine would have another horizontal pivot for the milling head, this time perpendicular to the fifth axis.  CNC milling machines are traditionally programmed using a set of commands known asG-codes. G-codes represent specific CNC functions in alphanumeric format.

Working of CNC lathe MachineThe VICE: This holds the material to be cut or shaped. Material must be held securely otherwise it may 'fly' out of the vice when the CNC begins to machine. Normally the vice will be like a clamp that holds the material in the correct position. The GUARD: The guard protects the person using the CNC. When the CNC is machining the material small pieces can be 'shoot' off the material at high speed. This could be dangerous if a piece hit the person operating the machine. The guard completely encloses the the dangerous areas of the CNC. The CHUCK: This holds the material that is to be shaped. The material must be placed in it very carefully so that when the CNC is working the material is not thrown out at high speed. The MOTOR: The motor is enclosed inside the machine. This is the part that rotates the chuck at high speed.The LATHE BED: The base of the machine. Usually a CNC is bolted down so that it cannot move through the vibration of the machine when it is working. The CUTTING TOOL: This is usually made from high quality steel and it is the part that actually cuts the material to be shaped.

THEORYComputer Numerical Control (CNC) is one in which the functions and motions of a machine tool are controlled by means of a prepared program containing coded alphanumeric data. CNC can control the motions of the work piece or tool, the input parameters such as feed, depth of cut, speed, and the functions such as turning spindle on/off, turning coolant on/off.

ApplicationsThe applications of CNC include both for machine tool as well as non-machine tool areas. In the machine tool category, CNC is widely used for lathe, drill press, milling machine, grinding unit, laser, sheet-metal press working machine, tube bending machine etc. Highly automated machine tools such as turning center and machining center which change the cutting tools automatically under CNC control have been

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developed. In the non-machine tool category, CNC applications include welding machines (arc and resistance), coordinate measuring machine, electronic assembly, tape laying and filament winding machines forA CNC system consists of three basic components

1. Part program2. Machine Control Unit (MCU)3. Machine tool (lathe, drill press, milling machine etc)

A Flow DIAGRAM OF CNC

Question answer related to CNC machineQ. No.1. What is CNC?Ans:- Computer Numerical Control (CNC) is one in which the functions and motions of a machine tool are controlled by means of a prepared program containing coded alphanumeric data.Q.NO.2 What is the application of CNC?Ans: - The applications of CNC include both for machine tool as well as non-machine tool areas. In the machine tool category, CNC is widely used for lathe, drill press, milling machine, grinding unit, laser, sheet-metal press working machine, tube bending machine etc.Q.No. 3. What is the advantage of CNC ?Ans:- The benefits of CNC are as follows –

(1) high accuracy in manufacturing,

(2) short production time,

(3) greater manufacturing flexibility,

(4) reduced human error.

Q.No.4.What is the element of CNC ?ANS;- A CNC system consists of three basic components which is given below 1 . Part program2 . Machine Control Unit (MCU)3 . Machine tool (lathe, drill press, milling machine etc)

Q.No. 5 What is CNC control panal ?

Ans :- A CNC machine is normally controlled by a computer and software. However, most CNC machines have a range of controls for manual use.

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EXPERIMENT NO. 04

OBJECT: -To study and operate the PLC controler and oval type conveyer belt system

EQUIPMENT: - PLC controller, Oval conveyer belt , air filter etc.

SPECIFICATION:- Specification of oval type conveyer belt

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Theory Automatic ConveyorAutomatic Conveyor for Industrial Automation consists of two object sensors, rpm sensor, and rpm control circuit which controls the speed of the motor driving the conveyor. The object sensors which detect the objects sends signal to the motor driving circuit to on/off the motor. It work on the elecric pulses as electronic puces is given it move and again it stopped at requred position according to the PLC to load the work piece and work material PROGRAM LOGIC CONTROL (PLC)

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Control engineering has evolved over time. In the past humans were the main method for controlling a system. More recently electricity has been used for control and early electrical control was based on relays. These relays allow power to be switched on and off without a mechanical switch. It is common to use relays to make simple logical control decisions. The development of low cost computer has brought the most recent revolution, the Programmable Logic Controller (PLC). The advent of the PLC began in the 1970s, and has become the most common choice for manufacturing controls. PLCs have been gaining popularity on the factory floor and will probably remain predominant for some time to come. Most of this is because of the advantages they offer.• Cost effective for controlling complex systems.• Flexible and can be reapplied to control other systems quickly and easily.• Computational abilities allow more sophisticated control.• Trouble shooting aids make programming easier and reduce downtime.• Reliable components make these likely to operate for years before failure.

PLC ConnectionsWhen a process is controlled by a PLC it uses inputs from sensors to make decisions and update outputs to drive actuators, as shown in Figure 1. The control loop is a continuous cycle of the PLC reading inputs, solving the ladder logic, and then changing the outputs. Like any computer this does not happen instantly. Figure 2 shows the basic operation cycle of a PLC. When power is turned on initially the PLC does a quick sanity check to ensure that the hardware is working properly. If there is a problem the PLC will halt and indicate there is an error. For example, if the PLC power is dropping and about to go off this will result in one type of fault.

Figure 1 -The Separation of Controller and Process

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Figure 2- The Scan Cycle of a PLC

Ladder diagram:Ladder logic is the main programming method used for PLCs.Ladder diagrams are the most commonly used diagrams for nonelectronic control circuits. They are sometimes called elementary diagrams or line diagrams. Two types of ladder diagrams are used in control system: the control ladder diagram and the power ladder diagram. The control ladder diagram has two active functional lines. Some of the common practices for the format of control ladder diagram are illustrated by this figure. Those practices are as follows:

Compressed Air FiltersAir filter are use to remove the dirt and dust from air so that only pure air is supplied to the syste normoly used air filter is Ballston compressed air filters which remove 99.99% of 0.01 micron particles of oil, water, and dirt from compressed air and other gases. The liquid releases from the filter cartridge to an automatic drain as rapidly as it enters the filter. This allows

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the compressed air filter to continue removing liquids without loss of efficiency or flow capacity.

Q.No.1. On which logic first PLC program was design ?Ans :- The first PLCs were programmed with a technique that was based on relay logic wiring schematics. This eliminated the need to teach the electricians, technicians and engineers how to program a computer - but, this method has stuck and it is the most common technique for programming PLCs today.

Q.No. 2. Give two example of where a PLC could be used ?Ans:- In conveyer belt and CNC PLC are used to control the motion and task.

Q.No. 3. Why would relays be used in place of PLCsAns:- for some cases is simple and cost effective relay be used in place of PLCs

Q.No 4. How many types of Ladder Logic in plc ?Ans: In ladder logic there are multiple types of outputs, but these are not consistently available on all PLCs. Some of the outputs will be externally connected to devices outside the PLC, but it is also possible to use internal memory locations in the PLC.

Q.No 5. Write the component of PLC .Ans;- The PLC has three components;

1) Central Processing Unit CPU, 2) Inputs, 3) Outputs.

EXPERIMENT NO-5

Object:- To write and run the CNC program for the Lathe Machine for the given drawing using CNC train simulator

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Equipments Required:- Computer, CNC lathe Machine

Theory:- A Part Program is a list of coded instructions which describes how the designed part, or component, will be manufactured. This part program is also called the CNC File. These coded instructions are called data - a series of letters and numbers. The part program includes all the geometrical and technological data to perform the required machine functions and movements to manufacture the part. The part program can be further broken down into separate lines of data, each line describing a particular set of machining operations. These lines, which run in sequence, are called blocks. A block of data contains words, sometimes called codes. Each word refers to a specific cutting/movement command or machine function. The programming language recognized by the CNC, the machine controller, is an International Standards Organisation code, which includes the G and M code groups. Each program word is composed from a letter, called the address, along with a number.

Motion Command Codes:-

G CODES:- Set preparatory machine functions such as rapid transverse mode, feed mode and active tool length offsets.

M CODES:- Perform a miscellaneous machine function such as automatic tool changes, coolant control and spindle operations.

Types of Formats:-

1. Tab Sequential Format

2. Fixed Format

3. Word Address Format

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PROGRAM BLOCK

Sequence Number (N) Preparatory Word (G) Coordinates (X-Y-Z)

Tool Selection (T) Spindle Speed (S) Feed Rate (F)

Miscellaneous Command (M) End of Block (E.O.B)

For Example:- N10 GOO X30 Z-20 F10 S200 T01 M30

Steps in Programming:-

1. Start- work piece zero point, cutting speed, feed, spindle rotation, speed limit

2. Facing

3. Roughing Process

4. Cutting

5. Close- stop spindle, stop coolant, program stop

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FIGURE

PROGRAM:-

N01 G59 X0 Z210

N02 G96 V200 T0202 M03

N03 G92 S2000 M08

N04 G00 X20 Z0

N05 G01 X-1 Z0 F0.2

N06 G00 X20 Z0

N07 G71 P80 Q90 I0.2 K0.2 D2 F0.2

N08 G26

N09 N80

N10 G46

N11 G00 X0 Z0

N12 G01 X4 Z0

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N13 G01 X4 Z-15

N14 G02 X8 Z-20 R10

N15 G01 X8 Z-35

N16 G03 X-18 Z-45 R15

N17 G01 X-18 Z-50

N18 G40

N19 G26

N20 G96 V200 T0101 M04

N21 G92 S2000 M08

N22 G00 X20 Z-51.5

N23 G01 X14

N24 G00 X15

N25 G01 X10

N26 G00 X11

N27 G01 X6

N28 G00 X7

N29 G01 X2

N30 G00 X3

N31 G01 X0

N32 G26

N33 M5 M9

N34 M0

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QUESTION AND ANSWERS

Q1. What is the meaning of G00, G01, G02?

Ans. G00- Positioning in Rapid

G01-Linear Interpolation

G02- Circular Interpolation (CW)

Q2. What does M03, M04 stands for?Ans. M03-Spindle on (clockwise rotation) M04-Spindle on (counterclockwise rotation)

Q3. Generally the CNC programming is written in which format?Ans. (a) Word Address Format (b) APT format

Q4. What is the function of HOME command?Ans. Pressing the X,Y or Z key will send the machine to its home position along the selected axis.

Q5. What is the function of DATUM command?Ans. Pressing the X,Y or Z key will datum that axis to zero.

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EXPERIMENT NO-6

Object:- To write and run the CNC program for the Milling Machine for the given drawing using CNC train simulator

Equipments Required:- Computer, CNC Milling Machine

Theory:- A Part Program is a list of coded instructions which describes how the

designed part, or component, will be manufactured. This part program is also

called the CNC File. These coded instructions are called data - a series of letters

and numbers. The part program includes all the geometrical and technological

data to perform the required machine functions and movements to manufacture

the part. The part program can be further broken down into separate lines of

data, each line describing a particular set of machining operations. These lines,

which run in sequence, are called blocks. A block of data contains words,

sometimes called codes. Each word refers to a specific cutting/movement

command or machine function. The programming language recognized by the

CNC, the machine controller, is an International Standards Organisation code,

which includes the G and M code groups. Each program word is composed from a

letter, called the address, along with a number.

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Motion Command Codes:-

G CODES:- Set preparatory machine functions such as rapid transverse mode,

feed mode and active tool length offsets.

M CODES:- Perform a miscellaneous machine function such as automatic tool

changes, coolant control and spindle operations.

Types of Formats:-

1. Tab Sequential Format

2. Fixed Format

3. Word Address Format

PROGRAM BLOCK

Sequence Number (N) Preparatory Word (G) Coordinates (X-Y-Z)

Tool Selection (T) Spindle Speed (S) Feed Rate (F)

Miscellaneous Command (M) End of Block (E.O.B)

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For Example:- N10 GOO X30 Z-20 F10 S200 T01 M30

Steps in Programming:-

1. Start- work piece zero point, cutting speed, feed, spindle rotation, speed limit

2. Facing

3. Roughing Process

4. Cutting

5. Close- stop spindle, stop coolant, program stop

FIGURE

PROGRAM:-

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T6 D6 ; Center punching drill

bit

G0 G90 G43 Z20 F200 S1800 M4 M8 M42

N10 G82 G99 X40 Y40 Z2 I-5 K300

N20 X-40

N30 Y-40

N40 X40

G80

G0 G44 Z100

T9 D9 ; Drill bit

G0 G90 G43 Z20 F200 S1050 M4 M42

G81 G99 X40 Y40 Z2 I-35

X-40 Y-40

G0 G44 Z100

T8 D8 ; Drill bit

G0 G90 G43 Z20 F200 S950 M4 M41

G81 G99 X-40 Y40 Z2 I-35

G0 X40 Y-40

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G0 G44 Z100

T13 D13 ; Reamer

G0 G90 G43 Z20 F100 S500 M4 M41

G85 G99 X-40 Y40 Z2 I-30 K200

X40 Y-40

G80

G0 G44 Z100

T12 D12 ; Tap

G0 G90 G43 Z20 F450 S300 M4 M41

G84 G99 X40 Y40 Z2 I-35 K200

X-40 Y-40

G80

G0 G44 Z100

T2 D2 ; End mill for

pockets

G0 G90 G43 Z20 F250 S1600 M4 M42

N50 G87 G98 X0 Y0 Z2 I-5 J-30 K30 B5 D2 H200 L-1

N60 G88 G98 X0 Y0 Z-3 I-10 J-25 B5 D2 H200 L1

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G80

G0 G44 Z100

M30

QUESTION AND ANSWERS

Q1. What is the meaning of G17, G18, G19?

Ans. G17-XY plane

G18-XZplane

G19- YZ plane

Q2. What does M03, M04 stands for?Ans. M03-Spindle on (clockwise rotation) M04-Spindle on (counterclockwise rotation)

Q3. Generally the CNC programming is written in which format?Ans. (a) Word Address Format (b) APT format

Q4. What is the function of HOME command?Ans. Pressing the X,Y or Z key will send the machine to its home position along the selected axis.

Q5. What is the function of DATUM command?Ans. Pressing the X,Y or Z key will datum that axis to zero

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