Numerical control machines are automatic cutting machines. If we compare the structure of a conventional cutting machine and a numerical control one, we will observe the following differences:
The measurement system for controlling the distance the car must travel along an axis consisted of a numerical scale. This scale was engraved on a cylinder that rotated as the axis moved and indicated the distance traveled. The maximum precision that could be achieved in such a system was 0.01mm.
In numerical control machines, the scale has been replaced by a linear measuring system that is coupled to the guides and indicates the distance traveled in an analog way (voltage variation) based on the photocell principle. This cell receives light energy from a source coupled to the system. The cell and light source have fixed positions and the guide moves together with the carriage. The guide is made up of different shades of gray that cause different voltage levels at the output of the reader cell. These voltage levels are associated with distances through a Hardware and Software system coupled to the machine. The precision that is achieved in the placement using this technology is of the order of 0.001 mm.
Accuracy: 0.001mm
FIGURE 7.1 Precision of a CNC machine.
The transmission system of the conventional machines consisted of the screw-nut type drive. The play that existed between these elements did not allow a more precise placement than specified (0.01 mm).
The transmission system used in the numerical control machines consists of the transmission of the ball screw-nut type. In this mechanism, a set of pellets are inserted between the screw and the nut, which results in a decrease in the existing play between the mechanical elements, achieving a more exact placement (of the order of 0.001 mm).
The motors in traditional cutting machines were three-phase alternating current motors. The motors used in numerical control machine tools are direct current motors. These motors are controlled by electronic devices. In a traditional machine the movement of the carriages along the axes was carried out by manipulating cranks. The operator would turn the crank and the cart would travel a given distance. A scale associated with the crank indicated the distance traveled by the car.
Numerical control machine tools have a control panel. This panel works as an interface between the machine and the user and through it the numerical control program is entered. This program is a set of instructions that are converted into orders (voltages), and actuate the movement of the cars through the control cards. The sequence of the program follows a logic that goes according to the path of the cutting tool. Toolpaths are based on manufacturing analysis that is performed prior to program generation. Tool travel produces machined surfaces. The set of surfaces constitutes the machined part.
From the above statements we can conclude that numerical control is a manufacturing language. The structure of the language and its semantics have been defined according to the traditional generation of machined surfaces using conventional machines. The semantics and structure are established in international standards.
PROGRAMMING LANGUAGE
The steps to follow for numerical control programming are similar to those established in manufacturing.
- Understanding of the part definition drawing, which must contain:
Dimensional information.
The dimensional and shape tolerances allowed.
The surface finish of the part
The material of the part
Other data
From the analysis of this drawing, the programmer obtains the set of surfaces that will be machined, the dimensions of the blank and the cutting tools that will be used in the process.
- Once known:
The set of surfaces to be machined in the process
Cutting tools.
Cutting parameters
The dimensions of the blank.
The dimensions and tolerances of the finished part, the numerical control program can be written.
- Once the numerical control program has been generated, it is necessary to enter it into the memory of the machine. In this process the control panel is used. When the introduction of the program has finished the manufacture of the part can be started. The tools must be in their positions. The reference system used in the defined programming. The tool compensators entered in the corresponding memory of the machine and the coolant contained in the corresponding tank.
COORDINATE SYSTEMS IN NUMERICAL CONTROL
When the position to which the tool is to move has been programmed, the Computerized Numerical Control system moves the tool to that position using the coordinates contained in the dimensional words of the block. For the specific machine we are studying, three different types of coordinate systems are defined:
- The coordinate system of the machine The work coordinate system The reference coordinate system.
THE COORDINATED SYSTEM OF THE MACHINE
The origin of this system is known as machine zero. This point is defined by the machine manufacturer. The machine coordinate system is established when the machine is turned on and the tool is brought to the reference point.
Once the machine's reference system has been established, it cannot by definition be changed from a local or working system. The only possibility for the system to be erased is for the machine to be turned off.
THE POINT OF REFERENCE
The position of this point generally coincides with the placement marks on the measuring rulers, because these marks are generally found at the ends of the rulers, the machine zero origin point is defined at the ends of the machine stroke. When the machine is turned on the operation of bringing the machine to its reference point is the first task to be executed. Once this point is reached the machine's reference system is established.
THE COORDINATED WORK SYSTEM.
The coordinate system used in the machining of the part is known as the work coordinate system. The origin of this system is defined in a useful point for programming the geometry of the part. The coordinate work system can be established using either of the following two methods:
Using function G92.
Using functions G54-G59.
ESTABLISHMENT OF THE WORKING COORDINATE SYSTEM USING THE G92 FUNCTION.
In this case, in the same block where the G92 function is programmed, the coordinates of the work origin are entered. For example:
G92 X90 Y78 Z-67
The coordinates specified in the previous block locate the position of the origin of the coordinate system with respect to machine zero. To obtain the coordinates of the origin of the reference system, the cutting tool can be used. The following steps are used to explain the procedure to be followed:
- The workpiece is placed on the machine table and clamped using any of the known clamping devices The work tool is rotated using the MDI modeThe cutting tool is moved until it touches one of the perpendicular surfaces to one of the coordinate axes. The value of the coordinate read from the numerical control is subtracted or added to the radius of the tool, depending on the direction of the coordinate axis. At that time the position of the tool axis along the considered axis is established. This is because the zero-dimensional origin of the tool is located at the point of intersection of the axis of rotation of the tool and the base on the work spindle where the cutting tool rests.
Example. If we assume that the tool has a diameter of 10 mm to the position marked on the control panel screen, 5 mm that is associated with the radius of the cutting tool must be subtracted from it. In the case of the Y axis, the coordinate read on the control panel is subtracted 5 mm. In the case of the Z axis, the length of the tool must be considered. If only one cutting tool will be used in the machining of the part: the coordinate that appears on the control panel can be taken, when the surface perpendicular to the axis of the tool is rubbed by the tip of the cutting tool. In the memory of the tooling the length of the tool is considered as zero.
When several tools are used in the process, the work spindle is brought to coincide with the surface to be machined. The coordinate that is read in the control panel will be the coordinate of the origin. The dimensions of the tool are included in the corresponding memory location. Compensation is done automatically when the tool is selected.
Once the coordinates of the origin of the work coordinate system are known, function G92 X_ Y_ Z_ is programmed. The control transfers the origin of coordinate system to the machine zero point defined by X, Y and Z.
ESTABLISHMENT OF THE WORKING COORDINATE SYSTEM USING FUNCTIONS G54-G59.
Six different coordinate systems can be established using the G54-G59 function set. These coordinate systems are established by entering into the memory of the machine the coordinates, with respect to machine zero, of the origins of the working systems. In the numerical control program the work origin is activated by programming the function corresponding to the memory location where the coordinates of its origin were stored.
| G54 | WORK SYSTEM 1 |
| G55 | WORK SYSTEM 2 |
| G56 | WORK SYSTEM 3 |
| G57 | WORK SYSTEM 4 |
| G58 | WORK SYSTEM 5 |
| G59 | WORK SYSTEM 6 |
Example:
G55 G00 X20 Z100
In this case, the placement of the tool is carried out at the positions specified in the dimensional words. These coordinates are located with respect to the work system 2 due to the programming of function G55.
LOCAL REFERENCE SYSTEMS
While programming in a work coordinate system, it is convenient to have a defined local system. The local system is specified with respect to the work coordinate system by using function G52. The origin of this system is defined in the dimensional words that accompany the main function. For example, when programming:
G52 X20 Y45 Z32
With which, in the specified position e! origin of a new coordinate system. The direction of the axes of the new defined system coincides with the directions of the axes of the work coordinate system. When a local system is defined, movement instructions that are programmed in absolute mode will refer to the defined local system. The local system can be changed by programming function G52 accompanied by the coordinates of the new origin. The local system can be overridden by programming function G52 accompanied by the dimensional words equal to zero.
SELECTION OF THE MACHINING PLANE
In applications related to circular interpolations and tool radius compensation, the selection of the machining plane allows the control system to know the axis perpendicular to the machining plane and the axes with respect to which the interpolation and compensation of the tool radius. tool can be run. The definition of the machining plane is carried out by programming the following functions:
| G17 | DEFINITION OF THE XY PLANE |
| G18 | DEFINITION OF THE XZ PLANE |
| G19 | DEFINITION OF THE YZ PLANE |
ABSOLUTE AND INCREMENTAL PROGRAMMING
In numerical control there are two possible ways to specify, the values of the dimensional words. The difference between these two forms is the reference used in the specification:
G90 FUNCTION.
In the case of coordinates specified in absolute form, the G90 function is used. The coordinates specified with respect to this system must always be referred to the currently active coordinate system. Example:
G90 GOO X30 Y60
G91 FUNCTION.
In this case, the position to which the cutting tool has to move is programmed by means of the words expressed with respect to the previous point defined. Example:
G91 G00 X20 Y30
THE FUNCTION OF THE TOOL
The manufacturing process of a part generally uses several cutting tools in its operations (in manufacturing these operations are known as phases of the process). For _ execution of each phase, a tool must be placed on the work spindle. In numerical control, the tool change is carried out automatically by programming a specific order. The dimensions of the tool are programmed using the static and dynamic compensators of the tool.
The change of the cutting tool is specified using the word T. When this function is programmed in conjunction with the auxiliary function MO6 (automatic tool change) the cutting tool moves to the automatic change position. In this position the tool carousel removes the active tool on the work spindle and in its place places the tool whose position was specified under the word T. Example:
M6 T2
When the above command is executed, the tool moves to the automatic change position, the carousel removes the currently active tool and places tool number 2 from the carousel on the work spindle.
G00 FUNCTION.
When this function is programmed, the tool travels to the programmed position, following a straight line at a speed specified in the control system. Generally this function is used to position the cutting tool from one point to another, within the workspace of the machine. When a G00 function is executed, the tool is accelerated to a predetermined speed.
When the control detects the approach to the programmed position, the tool decelerates.
The programming of this function can be done in absolute or incremental coordinates. In addition, care must be taken to program the movements of the tool considering the sequence of movements. The first tool movement must be programmed in a plane parallel to the machining plane. Once the tool is positioned, it can descend along the axis perpendicular to the machining plane. Similarly, when the tool is withdrawn after the cutting process, it must be moved in the direction perpendicular to the machining plane and away from it, and subsequently the tool must be moved in a plane parallel to the machining plane.
FUNCTION G01.
When this function is used, the tool moves to the programmed position, following a straight line between the point where it is located and the programmed point. The tool travel speed is specified in the word F found in the same block where function G01 was programmed. The programming of this function can be done in absolute or incremental coordinates.
The recommendations given in the programming of the G00 positioning function should be taken into account when programming using the G01 function.
GO2 and GO3 FUNCTIONS.
Functions that describe arcs of a circle are known as circular interpolation functions. In these functions, the end point to be reached is programmed in the dimensional words that accompany the G function. Thus, the end point of the arc is specified by the words X, Y or Z, where the quantities can be expressed in absolute or incremental coordinates.. You must also program the radius of the circle that will be described or alternatively the coordinates of the center of the radius and the feedrate of the tool. An important aspect that must be considered is that the machining plane where the arc of a circle is defined must be programmed in a previous block. In addition to these values, the direction of the tool path must be programmed when the function is executed:
The G02 function defines an arc of a circle in a clockwise direction.
The GO3 function defines an arc of a circle in the counterclockwise direction.
The consideration raised above regarding the plane where the arc of a circle needs to be programmed in a block prior to the one where the circular interpolation function is programmed, is due to the fact that the circular interpolation functions are defined in a plane. The dimensional words to be used depend on the plane where the arch will be machined.
Arc in the XY plane.
G17 (G02 / G03) X_Y_ (R_ / I_J_) F_
Arc in the XZ plane
G18 (G02 / G03) X__ Z__ (R __ / I__ K__) F__
Arc in the YZ plane
G19 (G02 / G03) X__ Z__ (R __ / J__ K__) F__
In the first parentheses used, the direction of the path is defined, while in the second parenthesis the radius of the arc of a circle or the coordinates of the center of the arc are programmed.
Relevant considerations in programming circular interpolation functions.
When the arc of the circle exceeds 180 degrees, the radius of the circle must be specified with a negative value
When the value of the radius cannot be specified, the coordinates of the center of the circle must be given, using the words I, J or K:
I in a coordinate parallel to the X axis
J in a coordinate parallel to the Y axis
K in a coordinate parallel to the Z axis
The position of the end point of an arc of a circle is specified by the dimensionless words X, Y or Z and can be expressed in absolute or relative coordinates:
For the case of programming the coordinates in absolute mode, the coordinates are specified in absolute mode, the coordinates are specified with respect to the origin of the active coordinate system. The programming block will consist of the words:
N… G… X… Y… I… J… F…
Where G specifies the direction of movement. X and Y will be the coordinates of the end point of the arc I, J will be the coordinates of the center of the circle.
For the case of relative mode programming, the coordinates will be specified with respect to the starting point of the arc.
The determination of the coordinates of the end point must be made relative to the start point of the arc.
The determination of the coordinates of the center of the circle is carried out with respect to the initial point of the arc.
The arc machining programming will be:
N… G… X… Y… I… J… F…
CUTTING SPEED
The linear speed generated between the cutting tool and the workpiece due to the rotation of any of the parts when the machining process is carried out, is known in manufacturing as the cutting speed. Since we refer to a relative speed, this is presented on the surface where the tool and part interact.
The stresses generated in the manufacturing process have a decisive influence on the temperature distribution in both the cutting tool and the workpiece. The temperature distribution in the tool determines, on the one hand, the change in its mechanical properties, which directly influences the duration of its cutting edge, the wear rate and, consequently, the machining precision. While the temperature distribution in the piece determines its mechanical properties, its surface quality and the dimensional precision obtained in the process.
In manufacturing, the units of cutting speed are generally expressed as:
In the metric system: (mm / minute) or (mm / revolution)
In the English system: (inches / minute) or (inches / revolution)
Because the linear velocity tangent to the rotating surface owes its nature to an angular velocity, its calculation is based on the equation of rotational motion:
V = px D x S / 1000
Where: D = Diameter of the rotating part.
V = Linear speed of the rotating part on the tangent surface.
S = Angular speed of the rotating part.
In the case of CNC machining centers and mills, the rotating part is the cutting tool. The piece is mounted on a work surface, it performs programmed linear movements that are related to the geometry of the contour, defined in the drawing of the piece.
AUXILIARY FUNCTIONS M
This type of function is used as a complement in numerical control programming. The M functions control operations that aid the cutting process. The main M functions used in numerical control are:
FUNCTION M2.
Terminates program execution up to the last instruction line.
FUNCTION M3
Rotating the cutting tool in a clockwise direction. Followed by the letter S, specifies the speed value in RPM.
FUNCTION M4
Rotating the cutting tool counterclockwise. Same as above function
FUNCTION M5
Stop spindle turning
FUNCTION M6:
Automatic tool change.
FUNCTION M8:
Refrigerant application to the process
M9 FUNCTION:
Refrigerant shutdown.
M30 FUNCTION:
The execution of the program ends.
NOTE: Before turning on a CNC machine you have to verify if it has the necessary conditions to work, in the case of this TRIAC FANUC machine, the parameters are: The pressure should be between 90 and 120 Psi, you should also verify that the oil contains enough B: P oil. CS 68.
Figure 7.2 Pressure gauge location
PRACTICE No 1
OBJECTIVE
At the end of the practice, the student will know the main keys on the control panel and the procedure for turning on and off the TRIAC FANUC numerical control milling machine.
INTRODUCTION:
Numerical control machines nowadays have been satisfying the demands of the industry, therefore it is necessary for the student to know in a brief way the operation and programming of these, since at the moment he is in the industry, it is it is very sure that you will find one and therefore it is necessary that you know its operation and way of operating.
EQUIPMENT.
- TRIAC FANUC CNC milling machine.
DEVELOPING:
1.- Turning on the system:
Note: Before starting the machine, verify that there is air in the system, checking the pressure gauge located on the lower left side of the machine, the pressure should be between 90 and 120 Psi; It should also be verified that the oil tank contains enough of it.
1.1.- Turn on the machine by turning the red knob to the right, located on the back of the machine.
1.2.- Turn on the monitor by pressing the green button located in the upper left part of the control panel.
2.- Start the heating process of the machine for 5 minutes at a speed of 750 RPM.
2.1.- Press MDI and give the instructions M03 + INPUT, S750 + CYCLE START:
3.- KEYS IDENTIFICATION:
DATA INPUT PANEL
| SCROLL AND ALPHANUMERIC KEYS | |
| RESET KEY | Reset any alarm messages. |
| CURSOR KEYS | Moves the cursor through the blocks of the program. |
| PAGE KEYS | Moves the cursor through the pages of the program. |
| ALPHANUMERIC CHARACTER KEYS | Used to enter the necessary information in a numerical control program. |
FIGURE 7.4 screen and data entry panel.
| EDIT KEYS |
| ALTER | Used to alter the values of words. |
| INSERT | Used to insert the words in a block. |
| DELET | Used to erase words. |
| I, #, EOB | Enters end-of-block character. |
| DOG | Cancels a word before the EOB instruction is entered. |
| INPUT | It allows the introduction of information to the machine. For example it allows the introduction of a program from an external source (a computer) |
| OUTPUT / START | It allows the output of information from the machine. For example send a program to an external source. |
| OPTION SELECTION MODES |
| POS | Position of the tool on the different axes. |
| PRGRM | Selection of the program to run. |
| OFFSET MENU | Tool compensators (radius and length) |
| DGNOST-PARAM | Diagnosis of the machine and software parameters. |
| OPR-ALARM | Displays alarm messages to the operator. |
| AUX-GRAPH | This machine does not have this option. |
FIGURE 7.5 Editing keyboard.
Next we have the diagram of the operation panel, which is divided into four sections, which are: program protection unit, automatic operation panel, manual operation panel and emergency stop, and manual override.
The program protection unit has the function of protecting the programs stored in the machine against accidental deletion.
FIGURE 7.6 Control Panel
- PROGRAM PROTECTION UNIT
When in the ON position, it protects the programs. When in the OFF position, it allows full program editing.
2.- AUTOMATIC OPERATION PANEL
| SOURCE OF THE PROGRAM | |
| CAR | Is selected to run a program |
| EDIT | Select to edit a program |
| MDI | It is selected to enter and execute a single block of information |
| OPERATION SELECTION | |
| SING. BLOCK | It allows the execution of the program block by block |
| BLOCK DELETE | When a program is executed, those blocks that include the / sign at the beginning of the block are ignored |
| OPT STOP | Used in conjunction with the M01 instruction to program an optional program stop |
| DRY RUN | Test the program. This test consists of executing the program at a constant speed |
| PRG TEST | Test the program. This test consists of executing the program ignoring all the M functions. |
| AXIS INHIBIT | Test the program. This test consists of executing the program inhibiting all axes |
| EXECUTION | |
| CYCLE START | Starts the execution of a program or a block |
| CYCLE STOP | Program stop |
| PRG STOP | Program stop after executing the block where the stop has been ordered |
3.- AUTOMATIC OPERATION PANEL
| OPERATION | |
| HOME | It is what is known as “machine zero”, that is, it sends the tool to that position. |
| JOG | Moves the axes to the feedrate placed on the OVERRIDE |
| INC JOG | Move the axes in increments of 0.001, 0.01 and 1 |
| MPG | Manual pulse generator (Electronic manual control) |
| TEACH | Enter the current position of the machine into the program |
| OFFSET MESUR | Registers the current position of movement to enter the OFFSET's of the tool |
| FEEDBACK MULTIPLIER | |
| LOW X 1 | Select to modify incremental mode in INC JOG or Crank mode |
| MEDL x 10 | Increase advancement to 10% |
| MEDL x 100 | Increase progress to 100% |
| MEDL x 1k | Multiplier for INC JOG mode |
| HIGH | Multiplier at full speed |
| SPDL DEC | Decrease spindle speed (100%) |
| SPDL 100% | Returns the spindle speed to the programmed value |
| SPDL INC | Increase spindle speed (100%) |
| DIRECTION OF THE AXES | |
| - X | Movement in negative direction in X |
| - AND | Movement in negative direction in Y |
| - Z | Movement in negative direction in Z |
| TRVRS | Fast movement |
| + X | Movement in the positive direction in X |
| + And | Movement in positive direction in Y |
| + Z | Movement in positive direction in Z |
| SPINDLE | |
| SPDL CW | Spindle rotation clockwise |
| SPDL STOP | Stop spindle turning |
| SPDL CCW | Spindle rotation counterclockwise |
| REFRIGERANT | |
| CLNT ON | Activated refrigerant |
| CLNT OFF | Refrigerant off |
| CLNT AUTO | Refrigerant operated automatically by program |
Figure 7.8 Manual Operation Panel
4.- SPEED CONTROL AND EMERGENCY STOP
| ABOUT MANUAL ADVANCE TRAVEL |
| On manual travel of the advance of the program and fast movement.
Over travel of the feed ranges and direction of the axes |
| EMERGENCY STOP |
| Cut off all power to all motors |
FIGURE 7.9. Speed Control and Emergency Stop
| MANUAL FUNCTIONS | |
| Switched on | Turn on the cnc milling cutter |
| Off | Turn off the cnc milling cutter |
| Release tool | Manually release tool from tool holder |
| Rotate counterclockwise | Advances the tool carousel in that direction |
| I turn clockwise | Advances the tool carousel in that direction |
| Axis limit override | Allows exceeding the limits of the axes |
| Guard override | Removes overshoot protection from axles |
| Crank | It moves some of the axes in a similar way to a crank on a conventional machine |
FIGURE 7.10 Manual Function Controls
4.- PROCEDURE TO SEND HOME
4.1. The POS key is pressed.
4.2. When the X, Y and Z axes appear on the screen; we press the JOG key.
4.3. Now we move the table by pressing the + X key, until 50 appears on the screen.
4.4. Now we press the -Y key, up to -50.
4.5. Now we press the -Z key, up to -15.
4.6. Once this is done, we press the HOME key, and then the + Z key; we see that the tool moves upwards and 0 appears on the screen.
4.7. Now we press the + Y key, and the table will move outwards, 0 will appear on the screen.
4.8. Finally we press -X, and the table will move to the control panel, the screen will show 0. We have finished sending the machine to HOME.
- SYSTEM SHUTDOWN.
5.1. We press the POS key.
5.2. We press the red button located in the upper left part of the control panel. 5.3. We turn to the left the red knob located on the back
QUESTIONNAIRE
- Where is the knob for turning the machine on? What function does the JOG key have ? What function does the HOME key have ? Which key that shows the position of the table on the screen? How many axes do we have on the machine? ? Which key displays a program? Which key executes a program? Which key executes a program step by step? By means of which element we adjust the percentage advance speed. Mention how the shutdown procedure is carried out.
PRACTICE No.2
OBJECTIVE
At the end of the practice, the student will have acquired the basic knowledge to operate in the MDI (MANUAL DATE INPUT) mode, for manual data entry of the TRIAC FANUC computerized numerical control milling machine.
INTRODUCTION
Sometimes manual operation of the machine is necessary, so it is necessary for the student to know how to operate the machine by manually entering MDI data. either to make a facing or a special machining that has nothing to do with the program that is in the machine, also to know how each command that is indicated to the machine individually works.
EQUIPMENT
- TRIAC FANUC CNC milling machine.
MATERIAL
- Acrylic plate.
DEVELOPING
- SYSTEM SWITCH ON.
NOTE: Before starting the machine, verify that there is air in the system, seeing the pressure gauge located on the lower left side of the machine, the pressure should be between 90 and 100 psi; You will also need to verify that the oil reservoir contains enough oil.
1.1. Turn on the machine by turning the red knob to the right, located on the back of the machine.
1.2. Turn on the monitor by pressing the green button, located in the upper left part of the control panel.
1.3. The POS key is pressed.
1.4. When the X, Y and Z axes appear on the screen; we press the JOG key.
1.5. Now we move the table by pressing the + X key, until 50 appears on the screen.
1.6. Now we press the -Y key, up to -50.
1.7. Now we press the -Z key, up to -15.
1.8. Once this is done, we press the HOME key, and then the + Z key; we see that the tool moves upwards and 0 appears on the screen.
1.9. Now we press the + Y key, and the table will move outwards, 0 will appear on the screen.
1.10. Finally we press -X, and the table will move to the control panel, 0 will appear on the screen, We have finished sending the machine to HOME.
- Start the heating process of the machine for 5 minutes at a speed of 750 RPM.
2.1. Press MDI and give the instructions M03 + INPUT, S 750 + INPUT + CYCLE ST ART.
- CODES M's and G's.
CODES M's
| CODE | ACTION |
| M03 | Spindle rotation clockwise. |
| M04 | Spindle rotation counterclockwise. |
| M05 | Stops the spindle turning. |
| M06 | Automatic tool change. |
| M10 | Open the chuck. |
| M11 | Close the chuck. |
| M98 | Call applet. |
| M99 | Subprogram ends. |
G CODES.
For the execution of these commands, special care must be taken in the group, therefore, it is understood that two commands from the same group should not be written in a program line.
| CODE | CODE | ACTION |
| one | G00 | Quick laying. |
| one | G01 | Linear interpolation of work specifying feedrate. |
| one | G02 | Circular interpolation clockwise. |
| one | G03 | Circular interpolation against clockwise. |
| 0 | G28 | Return to the reference point. |
| 3 | G90 | Absolute programming. |
| 3 | G91 | Incremental programming. |
| 0 | G92 | Programs the origin of the work coordinate system. |
| 5 | G94 | Feed in feet per minute. |
| 5 | G95 | Feed in feet x revolution. |
- MDI MANAGEMENT.
To enter the MDI mode we will follow these steps: first we type MDI, then PRGM. Once the MDI mode has been displayed on the screen, G 's and M' s codes will be entered for manual operation of the milling machine.
4.1. Command the machine to make the tool change, so that it takes tool No. 1: by typing MO6, INPUT, T1, INPUT, CYCLE START.
4.2. Type in the alphanumeric panel the instruction to turn clockwise, with a speed of 1000 RPM following these steps, M03, INPUT, S 1000, INPUT, CYCLE START.
4.3. Now order the table to be positioned at the tool's reference point relative to the acrylic cap, which is done by the following instruction, GOO, INPUT, X188.686, INPUT, Y-136.3, INPUT, CYCLE S TART.
4.4. Now we will proceed to carry out a small “machining on one side of the plate, for which we will first put the tool in position by typing, GOO, INPUT, X10, INPUT, Y10, INPUT, CYCLE START.
4.5. We bring the. tool to the., acrylic cap but without doing any machining by typing, GOO, INPUT, Z-85, IMPUT, CYCLE START.
4.6. We drill at that point with a depth of 6 mm, and a feed rate of 0.25 ft / min. typing, G01, INPUT, Z-6, INPUT, F25, INPUT, CYCLE ST ART.
4.8. We go to another point by typing, GOO, INPUT, X34, INPUT, Y21, INPUT, CYCLE START.
4.9. We make a small perforation, here we are not going to specify the advance since as it is modal the previous advance instruction gives it to us by default, unless we modify it.
4.10. We type, GO1, INPUT, Z-1.5, INPUT, CYCLE START.
4.11. Now we are going to do a machining using radii through the GO3 command, in which we will make a circumference, first we will do half of it by typing, G03, INPUT, X-15, INPUT, Y15, INPUT, R10, INPUT, CYCLE START.
4.12. Now we do the other half by typing, GO3, INPUT, X15, INPUT, Y-15, INPUT, R10, INPUT, CYCLE START.
4.13. Now we take out the tool, GOO, INPUT, Z1.5, INPUT, CYCLE ST ART.
4.14. We go to another point by typing, GOO, INPUT,; X-10, INPUT, Y-15, INPUT, CYCLE START.
4.15. We are going to do a linear interpolation with X and Z, typing, GO1, INPUT, X20, INPUT, Z-5, INPUT, CYCLE START.
4.16. We take out the tool, GOO, INPUT, Z5, INPUT, _CYCLE START.
4.17. We go to another point by typing, GOO, INPUT, X15, INPUT, CYCLE ST ART.
4.18. We make a small hole, GO11 INPUT, Z-1.5, INPUT, CYCLE ST ART.
4.19. We do the linear interpolation with X and V, typing, G01, INPUT, X13, INPUT, Y30, INPUT, CYCLE START.
4.20. We take out the tool, G00, INPUT, Z86.5, INPUT, CYCLE START.
4.21. We send the table to the origin, typing, G28, INPUT, X0, INPUT, Y0, INPUT, CYCLE START.
4.22 We stop the spindle rotation by pressing the SPDL STOP key
At this point we have finished handling the MDI mode .
- SYSTEM SHUTDOWN
5.1 We press the POS key
5.2 We press the red button located in the upper left part of the control panel.
5.3 We turn to the left, the red knob located on the back of the machine.
QUESTIONNAIRE
1.- What is the procedure to enter the MDI mode of the TRIAC-FANUC milling machine ?
2.- Say the function of the G00 command .
3.- What operation does the M06 type machine perform ?
4.- Besides typing M06 on the machine, what other instruction is specified?
5.- Say the procedure to introduce an instruction through the MDI mode to the milling machine, and that this in turn execute it.
6.- How many instructions of the same group can be introduced to the milling machine through the MDI mode, so that it executes them in turn?
7.- What instruction enables the machine to execute a circular interpolation in a clockwise direction?
8.- What is the instruction that indicates to the machine a linear interpolation?
9.- What instruction is added to the G01 command, to indicate a feedrate in mm / min, or feet / min?
10.- What is the function of the G28 command ?
PRACTICE No. 3
OBJECTIVE
At the end of the practice, the student will have acquired the necessary knowledge to program the TRIAC FANUC computerized numerical control milling machine through the program editor.
INTRODUCTION
In the industry, as is known, numerical control machines are far above conventional ones, this is because there is a saving of time in terms of machining, tool change, and above all accuracy, this is because The necessary instructions for the elaboration of a piece, for this the study of the trajectory of the tool is previously made to save time, as well as the machining order, in this way the programmer will enter the ideal instructions into the machine, using the program editor.
EQUIPMENT
TRIAC FANUC CNC milling machine
Program protection key
MATERIAL
Acrylic plate
DEVELOPING
- POWER ON THE SYSTEM
NOTE: Before starting the machine, verify that there is air in the system, seeing the pressure gauge located on the lower left side of the machine, the pressure should be between 900 and 100 psi; You should also check that the oil reservoir contains enough oil
1.1. Turn on the machine by turning the red knob to the right, located on the back of the machine.
1.2. Turn on the monitor by pressing the green button, located in the upper left part of the control panel.
1.3. POS key is pressed
1.4. When the X, Y and Z axes appear on the screen , press the JOG key .
1.5. Now we move the table by pressing the + X key, until 50 appears on the screen .
1.6. Now we press the –Y key until -50.
1.7. Now we press the –Z key to -15.
1.8 Once this is done, press the HOME key, and then the + Z key; we see that the tool moves upwards and 0 appears on the screen .
1.9 Now we press the + Y key, and the table will move outwards, 0 will appear on the screen.
1.10 Finally we press –X, and the that will move to the control panel, the screen will show 0. We have finished sending the machine to HOME.
- Start the heating process of the machine for 5 minutes at a speed of 750 RPM.
2.1 Press MDI and give the instructions M03 + INPUT + CYCLE START.
- ENTERING THE PROGRAM EDIT MODE EDIT.
3.1 We press the EDIT key to enter the program editor.
3.2 To verify the existing programs in memory, type O + CURSOR KEY
3.3 To make a new program, we type O + PROGRAM NUMBER + EOB.
3.4 The following screen will appear.
3.5 At this moment, our program editor is ready for us to introduce the program we want.
- WRITING A PROGRAM
NOTE: The program that we are going to introduce is small and it will first indicate the work reference point, then it will execute a tool change, it will turn the spindle at a speed of 1000 RPM clockwise, it will be placed near our part and make a small hole, then it will go out and go to the safety point, stop the spindle and end the program.
| N10 | G62 X-188.686 Y136.3 Z60 |
| N20 | G90 G28 X-188.686 Y136.3 Z60 |
| N30 | M06 T0101 |
| N40 | M03 S1000 |
| N50 | G00 X31.65 Y31.75 |
| N60
N70 |
G00 Z-23
G01 Z-28 F25 |
| N80 | G00 Z60 |
| N90 | G28 X-188.686 Y136.3 |
| N100 | M05 |
| N110
N120 |
M99
M30 |
Once the program has been written on the machine, it will be executed on the machine, previously verifying it so that it does not find any fault or problem in the equipment. To run the program, these steps will be taken into account:
4.1 First press AUTO, then to execute it line by line, SINGL BLOCK, and later in each line CYCLE START, to execute the program SUPERVISION MUST BE ASKED FROM THE LABORATORY ADVISOR.
4.2 Finally, we will execute the complete program by typing AUTO and CYCLE START from the beginning of the program.
4.3 We exit the RUN option, pressing the EDIT key.
- SYSTEM SHUTDOWN
5.1 We press the POS key .
5.2 We press the red button located in the upper left part of the control panel.
5.3 We turn to the left, the red knob located on the back of the machine.
QUESTIONNAIRE
- What is the use of having a program editor in the control panel of the TRIAC FANUC milling machine? How easy is a program in the memory of the TRIAC FANUC milling machine? How do we enter the program editor of the TRIAC FANUC milling machine? What is the code to define our working reference point? What is the code that is used to do a circular interpolation? What is the code that tells the milling machine to do a machining linear interpolation? indicates to the router whenever a machining code is applied? What is indicated to the router when a circular interpolation code is applied to it? After indicating to the router the work reference point, where is the table and by what code? Whenever a tool change is made, where should the worktable be?
PRACTICE No. 4
OBJECTIVE
At the end of the practice, the student will have acquired the necessary knowledge to handle the TRIAC FANUC computerized numerical control bur, through the use of signals in a program, to know in this way when to open the channel, when to emit a signal, when to wait for it and when to close channel.
INTRODUCTION
The TRIAC FANUC CNC milling machine is able to establish communication with other equipment, in our case with the PUMA robot, so we have greater efficiency in the operation of a machining line, we could talk a lot about the scope that this gives us, but it would be redundant in terms of the CIM laboratory applications
EQUIPMENT
TRIAC FANUC CNC milling machine.
Program protection key.
MATERIAL
Acrylic plate.
DEVELOPING
- SYSTEM SWITCH ON.
NOTE: Before turning on the machine, verify that there is air in the system, seeing the pressure gauge located on the lower left side of the machine, the pressure should be between 90 and 100 psi; You will also need to check that the oil reservoir contains enough oil.
1.1. Turn on the machine by turning the red knob to the right, located on the back of the machine.
1.2. Turn on the monitor by pressing the green button, located in the upper left part of the control panel.
1.3. The POS key is pressed .
1.4. When the X , Y and Z axes appear on the screen; we press the JOG key .
1.5. Now we move the table by pressing the + X key, until 50 appears on the screen .
1.6. Now we press the –Y key, up to –50 .
1.7. Now we press the –Z key, up to –15.
1.8. Once this is done, we press the HOME key, and then the + Z key; we see that the tool moves upwards and 0 appears on the screen.
1.9. Now we press the + Y key, and the table will move outwards, 0 will appear on the screen.
1.10. Finally we press –X, and the table will move to the control panel, 0 will appear on the screen. We have finished sending the machine to HOME.
- Start the heating process of the machine for 5 minutes at a speed of 750 RPM.
2.1. Press MDI and give the instructions M03 + INPUT , S 750 + INPUT + CYCLE START.
Before starting to use the program, we will attach a list of G's and M's most commonly used codes to program the TRIAC FANUC milling machine:
CODES M's.
| CODE | ACTION |
| M02 | Terminate the program until the last line of instruction. |
| M03 | Spindle rotation clockwise. |
| M04 | Spindle rotation counter clockwise. |
| M05 | Stops the spindle turning. |
| M06 | Specific automatic tool change. |
| M30 | Finish the program. |
| M62 | Turns on input channel 1 for signal standby. |
| M64 | Turn off channel 1. |
| M66 | Wait for input signal 1. |
| M76 | Wait for entrance 1 to get off. |
| M98 | Call applet. |
| M99 | Subprogram ends. |
G CODES.
When using these codes, care must be taken not to write commands from the same group within the same block.
| CODE | CODE | ACTION |
| one | G00 | Quick laying. |
| one | G01 | Linear interpolation of work specifying feedrate. |
| one | G02 | Circular interpolation clockwise. |
| one | G03 | Circular interpolation against clockwise. |
| 0 | G04 | Fix positions. |
| 6 | G20 | It works in the English system. |
| 6 | G21 | It works in the metric system. |
| 0 | G28 | Return to safety position. |
| GROUP | CODE | ACTION |
| 7 | G40 | Cancels cut compensation |
| 5 | G94 | Feed in feet per minute |
| 5 | G95 | Feed in feet x revolution |
- PROGRAMMING WITH SIGNAL MANAGEMENT.
The handling of signals is very important for an automated line, since through these our teams communicate, and thus in this way they can carry out some action during the process.
For programming by handling signals from the TRIAC FANUC milling machine; First, you must know when to open the channel to wait for the signal, for example, in a certain program the milling machine must first receive the part from the outside, as is the most common case, then the milling machine places the table in The security point opens the channel specified to wait for a signal, after receiving the signal that the piece has been placed on the table, that the equipment that did it is already out of the table and that the door has been closed, then the router closes the specified channel, waits for the signal that the channel has been deactivated, and continues with the next programming line.
As we can see, there is a follow-up regarding the insertion of the commands for handling signals, which are very simple, now we will see a practical example of this in program 5 of the TRIAC FANUC milling machine, for which we press the O key on the alphanumeric keyboard, 5 and EOB.
A program will then appear, in which signals are handled between the TRIAC FANUC milling machine and the PUMA robot, which is as follows.
N10 G92 X-188,686 Y136.3 Z60;
N20 G90 G28 X-188,686 Y136.3 Z60;
N30 M62;
N40 M66;
N50 M64;
N60 M76;
N70 M06 T1;
N80 M03 S1500;
N90 M05;
N100 M06 T3;
N120 M62;
N130 M66;
N140 M64;
N150 M76;
N160 M99;
N170 M30;
- EXECUTING SIGNALS.
Now we will proceed to operate the TRIAC FANUC milling machine together with the PUMA robot, to have a more exact idea of what signal handling is.
4.1. POWER ON THE SYSTEM FOR THE PUMA ROBOT.
4.1.1. Turn on the terminal (monitor).
4.1.2. Turn on the controller.
4.1.2.1. Set the AC POWER switch of the UNIMATION controller to ON.
4.1.2.2. Wait for the following message to appear on the screen:
Load VAL II from floppy (y / N) ?
4.1.2.3. As VAL II system is resident in the memory of the controller, the answer N.
4.1.2.4. Wait for the following message to appear on the terminal screen:
VAL 11560.2.06
Initialize (Y / N)?
NOTE: This question must always be answered with N, otherwise all the content of CMOS memory will be lost.
4.1.3.. TURN ON THE ARM SERVOMOTORS.
4.1.3.1. Place one hand on the ARM POWER OFF button on the controller, without pressing it.
4.1.3.2. Press the ARM button . POWER ON of the controller.
NOTE: If the arm of the robot starts moving when the button is pressed ARM POWER ON, you must immediately press the button ARM POWER OFF, as any movement in this stage indicates that something is wrong with the system.
4.1.4. CALIBRATE THE ARM.
4.1.4.1. Make sure the system is in COMP mode by pressing the COMP button on the Teach Pendant.
4.1.4; 2. In the terminal type e! CALIBRATE command, press the ENTER key and answer affirmatively to the system confirmation message with Y.4.1.4.3. Wait until the CAL indicator light on the handheld control unit goes off and the PROMPT “.” Appears on the display.
4.2. Once the PUMA robot is turned on, we type in the milling machine AUTO, CYCLE START, then the program will start executing, stopping at block N40 with the wait for signal M66 instruction .
4.3. Now we type in e! PUMA robot, signal 2, ENTER, then the mill will go to block N60 with the signal wait instruction to go to block
4.4. Now we type in the PUMA robot, signal 2, then the milling machine will go to the next blocks executing the program, until it stops at block N130, with the M66 signal wait instruction.
4.5. To this we type in the PUMA robot, signal 2, ENTER, then the milling machine will go to block N150, with the M76 instruction.
4.6. We type in the PUMA robot, signal 2, the program in the milling machine ends with the last instruction and is placed in the first block N10.
As we can see, the handling of signals in the milling machine is very simple, as long as the order is correct. Since a wrong location of the command would result in a bad execution of the same.
- SYSTEM SHUTDOWN..
5.1. TRIAC FANUC milling machine shutdown procedure.
5.1.1. We press the red button located at the top of the control panel.
5.1.2. We turn to the left, the red knob located on the rear pair of the machine.
5.2. The PUMA robot will also shut down, using the following procedure:
5.2.1. Bring the robot arm to its home position. From the terminal, type the command DO READY and press the ENTER key. Wait for the arm to be immobile in its original position.
5.2.2. Press the POWER OFF button on the controller.
5.2.3. Turn down the AC POWER controller's power switch and turn off the terminal.
QUESTIONNAIRE
- What is the purpose of signal handling in the industry? What is achieved in the milling machine when handling signals? With whom does the TRIAC FANUC mill communicate? Which channel does the mill turn on to communicate and by what code? With which code does the milling machine wait for a signal? What is the code to close the channel? By which code the mill is instructed to wait for a signal to continue down What command does the PUMA robot use to emit signals? What is the number that drive PUMA robot in command to output signal to TRIAC FANUC milling machine? Make a small program handling signals on TRIAC FANUC milling machine.
REFERENCES AND WEB LINKS - JOBS OF INDUSTRIAL ENGINEERING (UPIICSA - IPN)
- INTRODUCTION TO INDUSTRIAL ENGINEERINGwww.gestiopolis.com/recursos/documentos/fulldocs/ger1/introalaii.htm WORK METHODS ENGINEERINGhttp: //www.monografias.com/trabajos12/ingdemet/ingdemet.shtml WORK MEASUREMENT ENGINEERING: //http. monografias.com/trabajos12/medtrab/medtrab.shtml MEASUREMENT ENGINEERING: STANDARD TIME APPLICATIONShttp: //www.monografias.com/trabajos12/ingdemeti/ingdemeti.shtml METHOD ENGINEERING: PRODUCTION ANALYSIS 1http: //www.monografias.com /trabajos12/andeprod/andeprod.shtml METHOD ENGINEERING: PRODUCTION ANALYSIS 2http: //www.monografias.com/trabajos12/igmanalis/igmanalis.shtml METHOD ENGINEERING: JOB SAMPLINGhttp: //www.monografias.com/trabajos.com/ /immuestr.shtml STANDARD WEATHER MANUAL www.gestiopolis.com / resources / documents / fulldocs / ger / mantiemesivan.htm PLANT DISTRIBUTION AND MATERIALS HANDLING http://www.monografias.com/trabajos12/distpla/distpla.shtml FOUNDATIONS OF THE ECONOMY OF QUALITY SYSTEMS www.gestiopolis.com/recursos/documentos/fulldocs/fin/fundelacal.htmPAGOS OF SALARIES AND INCENTIVES IN INDUSTRIAL ENGINEERING www.gestiopolis.com/recursos/documentos/fulldocs/rrhh/pagosal.htm QUALITY CONTROL - ITS ORIGINShttp: //www.monografias.com/trabajos11/primdep/primdep.shtml QUALITY CONTROL - GRAPHICS FROM SHEWHARThttp: //www.monografias.com/trabajos12/concalgra/concalgra.shtmlMARKET RESEARCHhttp: //www.monografias.com/trabajos11/invmerc/invmerc.shtml PLANNING AND CONTROL OF PRODUCTION - FORECASTShttp: //www.monografias. com / trabajo13 / placo / placo.shtml INVESTIGATION OF OPERATIONS - LINEAR PROGRAMMINGhttp: //www.monografias.com / trabajo13 / upicsa / upicsa.shtml INVESTIGATION OF OPERATIONS - SIMPLEX METHODhttp: //www.monografias.com/trabajos13/icerodos/icerodos.shtml INVESTIGATION OF OPERATIONS - NETWORKS AND PROJECT ADMINISTRATION www.gestiopolis/fulldocs/documentos/ ger1 / iopertcpm.htm PRODUCTION PLANNING AND CONTROL: BALANCING OF ASSEMBLY LINES: MIXED AND MULTI-MODEL LINES
www.gestiopolis.com/recursos/documentos/fulldocs/ger1/pcplinen.htm PRODUCTION PLANNING AND CONTROL - LINE BALANCINGwww.gestiopolis.com/recursos/documentos/fulldocs/ger1/pycdelapro.htm COMPUTER ASSISTED MANUFACTURINGhttp: // www. monografias.com/trabajos14/manufaccomput/manufaccomput.shtml MANUFACTURING PROCESSES BY CHIP STARTINGhttp: //www.monografias.com/trabajos14/manufact-industr/manufact-industr.shtml INTRODUCTION TO MACHINE TOOLS.com/www.monografias.com/ jobs14 / maq-tool / maq-tool.shtml THEORY OF RESTRICTIONShttp: //www.gestiopolis.com/recursos/documentos/fulldocs/ger1/tociem.htm LEGISLATION AND MECHANISMS FOR INDUSTRIAL PROMOTIONhttp: //www.monografias.com/trabajos13/ legislac / legislac.shtml THEORY OF THE COMPANYhttp: //www.monografias.com/trabajos12/empre/empre.shtmlNON-DESTRUCTIVE TESTING - ULTRASOUNDwww.gestiopolis.com/recursos/documentos/ fulldocs / ger1 / disultra.htm DIFFICULTIES IN ISO STANDARDS QUALITY CERTIFICATION www.gestiopolis.com/recursos/documentos/ fulldocs / ger1 / difiso.htm
BASIC ENGINEERING SCIENCES
- Chemistry - Atomhttp: //www.monografias.com/trabajos12/atomo/atomo.shtml University Physics - Classical Mechanicshttp: //www.monografias.com/trabajos12/henerg/henerg.shtmlUPIICSA - Industrial Engineeringhttp: //www.monografias.com /trabajos12/hlaunid/hlaunid.shtmlMechanical Tests (Destructive Tests) http://www.monografias.com/trabajos12/pruemec/pruemec.shtml Classical Mechanics - One-dimensional Movementhttp: //www.monografias.com/trabajos12/moviunid/moviunid.shtmlQuímica - Physicochemistry Course at UPIICSAhttp: //www.monografias.com/trabajos12/fisico/fisico.shtml Biology and Industrial Engineeringhttp: //www.monografias.com/trabajos12/biolo/biolo.shtml Linear Algebra - UPIICSA Examshttp: / /www.monografias.com/trabajos12/exal/exal.shtml Electricity Laboratory Practices (UPIICSA) http://www.monografias.com/trabajos12/label/label.shtmlPractices of the UP Chemistry Laboratoryhttp: //www.monografias.com/trabajos12/prala/prala.shtmlPhysics Problems by Resnick, Halliday, Krane (UPIICSA) http://www.monografias.com/trabajos12/resni/resni.shtmlBiochemistryhttp: //www.monografias.com/trabajos12/bioqui/bioqui.shtml Code of Ethicshttp: //www.monografias.com/trabajos12/eticaplic/eticaplic.shtmlUniversity Physics - Oscillations and Harmonic Movementhttp: //www.monografias.com /trabajos13/fiuni/fiuni.shtmlChemical Production - The world of plasticshttp: //www.monografias.com/trabajos13/plasti/plasti.shtmlPlastics and Applications - Case Study at UPIICSAhttp: //www.monografias.com/trabajos13/ plapli / plapli.shtml Industrial Psychosociologyhttp: //www.monografias.com/trabajos13/psicosoc/psicosoc.shtmlLegislation for Industrial Promotionhttp: //www.monografias.com / trabajo13 / legislac / legislac.shtml Published Works of Pneumatics in Industrial Engineering Compressed air of the UPIICSAhttp: //www.monografias.com/trabajos13/compri/compri.shtmlNeumática e Ingeniería Industrialhttp: //www.monografias.com/trabajos13/unointn /unointn.shtml Pneumatics: Air Generation, Treatment and Distribution (Part 1) http://www.monografias.com/trabajos13/genair/genair.shtml Pneumatics: Air Generation, Treatment and Distribution (Part 2) http: // www.monografias.com / trabajo13 / geairdos / geairdos.shtml Pneumatics - Introduction to Hydraulic Systemshttp: //www.monografias.com/trabajos13/intsishi/intsishi.shtml Structure of Hydraulic Circuits in Industrial Engineeringhttp: //www.monografias.com/trabajos13 /estrcir/estrcir.shtmlPneumatics and Hydraulics - Power Generation in Industrial Engineeringhttp: //www.monografias.com / trabajo13 / genenerg / genenerg.shtml Pneumatics - Pneumatic Valves (applications in Industrial Engineering) Part 1http: //www.monografias.com/trabajos13/valvias/valvias.shtml Pneumatics - Pneumatic Valves (applications in Industrial Engineering) Part 2http: // www.monografias.com/trabajos13/valvidos/valvidos.shtml Pneumatics and Hydraulics, Hydraulic Valves in Industrial Engineeringhttp: //www.monografias.com/trabajos13/valhid/valhid.shtmlNeumática - Pneumatic Auxiliary Valves (Applications in Industrial Engineering) http: //www.monografias.com/trabajos13/valvaux/valvaux.shtml Industrial Engineering Problems in Pneumatics (UPIICSA) http://www.monografias.com/trabajos13/maneu/maneu.shtml Electrovalves in Control Systemshttp: // www.monografias.com/trabajos13/valvu/valvu.shtml Pneumatics and Industrial Engineeringhttp: // www.monografias.com/trabajos13/unointn/unointn.shtml Structure of Hydraulic Circuits in Industrial Engineeringhttp: //www.monografias.com/trabajos13/estrcir/estrcir.shtml Saving energyhttp: //www.monografias.com/trabajos12/ahorener/ahorener. shtmlTrabajo Publicados de Derecho del Centro Escolar AtoyacNociones de Derecho Mexicanohttp: //www.monografias.com/trabajos12/dnocmex/dnocmex.shtmlNociones de Derecho Positivohttp: //www.monografias.com/trabajos12/dernoc/dernoc.shtml Civil Family Lawhttp: //www.monografias.com/trabajos12/derlafam/derlafam.shtmlJuicio de amparohttp: //www.monografias.com/trabajos12/derjuic/derjuic.shtml Patrimonial crimes and Professional Responsibilityhttp: //www.monografias.com/trabajos12/derdeli /derdeli.shtmlIndividual Employment Contracthttp: //www.monografias.com/trabajos12/contind/contind.shtml The Family in Mexican Civil Lawhttp: //www.monografias.com/trabajos12/dfamilien/dfamilien.shtml The Family in Positive Lawhttp: //www.monografias.com/trabajos12/dlafamil/dlafamil.shtml Articles 14 and 16 of the Constitution de Méxicohttp: //www.monografias.com/trabajos12/comex/comex.shtml Individual Guaranteeshttp: //www.monografias.com/trabajos12/garin/garin.shtml Family and Lawhttp: //www.monografias.com/trabajos12/ lafami / lafami.shtmlcom / trabajo12 / lafami / lafami.shtmlcom / trabajo12 / lafami / lafami.shtml
