CNC programming language. Programming using a CAM system. Basic concepts and definitions

Having appeared in the middle of the last century, CNC machines have become reliable assistants for people in production. They process quickly, accurately and efficiently, at low cost. Individual pieces of equipment are combined into robotic production complexes.

Behind direct work Each machine is responsible for two specialists - and. But before they start their functional responsibilities, the programmer has to work hard.

A CNC machine tool programmer is responsible for solving many problems. They do:

• development of technical documentation, implementation and configuration of software, they are saved and systematized;
• purchasing and debugging equipment, putting into operation new programmable machines, monitoring their serviceability;
• training of personnel (operators) servicing CNC machines, technical consultations.

Who will be hired?

A college graduate without experience in the specialty can also fill the vacancy of a CNC machine programmer (though in a low category). He must have excellent training: theoretical knowledge of technological processes in this equipment; master the basics of programming and customizing software, experience working in AutoCAD. Of course, starting salaries are not so high, but there is professional growth ahead.

A slightly higher salary range awaits applicants with more than one year of experience as a software engineer. Another requirement: knowledge of technical terms in English and the ability to work in CAM/CAD.

A substantial salary will be offered by the employer to a candidate for a vacancy who has a higher education in his specialty and more than 2 years of experience.

Programming engineers of CNC machines (with over 3 years of experience) who are able to solve problems can count on the highest salary complex tasks in production. Most of the applicants are men, women are at the level of 2-3%, but they cope with programming tasks no worse than men. As for knowledge of English, every tenth software engineer speaks the language perfectly.

Range of specialist skills

Every employer wants to hire ready-made specialist who knows and can do a lot. Therefore, a CNC machine tool programmer is expected to perform typical functionality:

• development and implementation of software for machine tools;
• creating 3D models from drawings for their production;
• ensuring the operability of CNC equipment;
• fruitful training on programmable machines;
• systematization of technical documentation and archiving;
• ability to select equipment.

One hears such phrases that form the level of aspiration: “There is such a specialty as CNC (CNC - in English abbreviation), where you don’t have to do anything at all - the machine works itself! I wish I could get some training!” On the one hand, no one will pay for anything. On the other hand, there is some truth in this. When a CNC engineer has written the correct program and configured the machine correctly, his presence at the machine is not necessary. He really clearly works independently, but a specialist with a complex of knowledge and skills can achieve this state of affairs. That is why an experienced programmer-adjuster is in demand in all countries.

Specialization – technologist-programmer

The essence of technological preparation of production (TPP) is to carry out in total all the activities that contribute to readiness for the production of a certain type of product. All documentation, equipment, tools, workpieces, and software programs necessary to produce the required volume of products at the level of specified indicators must be in order.

The requirements for a CNC technologist-programmer are no less. Moreover, in many enterprises, a competent engineer with a higher education combines the functions of a technologist and a programmer, possessing the necessary professional skills.

Although for beginners and those without work experience, sometimes the bar is lowered by accepting a position with a secondary specialized technical education, making sure that the applicant can be classified as a confident AutoCAD user who knows the specifics of equipment and technology.

A technologist programmer of CNC machines with experience is already required to speak English at a level that is sufficient to read technical documentation. The issue of introducing products of a new range into production is also decided by a programmer technologist who will develop technological maps, and on their basis the UE.

Technological process is being designed

For this, various special knowledge is used, without which you cannot create a UE. This increases the requirements for the skill level of the technologist, who must, in the process of calculating the data that will become the basis of the program, competently apply technical means. He is called upon to be not only a programmer, but also a mathematician, an electronics engineer, and a good production organizer.

The technologist-programmer of CNC machines studies working drawings for their manufacturability, selects tools and equipment, and develops requirements for the quality of the workpiece.

Thus, all processing operations are highlighted in the form individual programs. Then, taking into account the configuration of the surfaces of the parts being processed, the trajectory of the tool’s movements and its speed in various modes are specified. The established sequence of the processing process is encoded and recorded on software.

What is the result? UP is a set of instructions addressed to each working part of the machine, which requires actions to be performed in a strict sequence.

The path to becoming a programmer

Engineers who have been trained in the metalworking profile are able, based on their qualifications and the customer’s technical specifications, to prepare the basis for creating a software package. But if they have the inclinations and programming skills, they will be a universal specialist - a CNC technologist-programmer. These are worth their weight in gold.

That is why many software engineers want to undergo training as a technologist in order to expand their skills. Or, conversely, a technologist is learning the basics of a new profession in an effort to become a programmer.

And it’s good when the enterprise administration is very interested in acquiring a second related profession by a specialist and is ready to facilitate this. For example, pay all the costs of his training.

But, alas, the desire to obtain additional qualifications does not always resonate with management. Why train them, spending money on it, if you can hire a ready-made specialist. Therefore, many Russians decide to learn programming on their own.

Learn again, but in practice

Where to start learning? Sometimes practice becomes a good school, when a person learns something new, overcomes difficulties, and step by step rises to the top of the profession. Sometimes acquiring practical experience lasts more than one year, but with wise mentors who are fluent in programming, it is possible to become a good specialist yourself.

One of the machine operators managed to master the profession of a CNC programmer with a second specialty - machine tool operator - through the Internet version of the PRACTICA course. There are weighed portions theoretical material(in compressed form) and a series of practical video tutorials, some reference materials. By the way, in the first video lesson they introduce you to the device and.

It is clear that immediately after studying the course no one will provide a position as a highly qualified programmer. It is necessary, while continuing to work as an operator, to master programming in practice. And within six months, demonstrate your knowledge and skills to management by offering the employee’s services in a new capacity.

Today, turning, milling, drilling and bending machines operate with CNC, and if they “stand up” at their home enterprise, a newly minted specialist with practical experience will be appreciated by others, offering good wage conditions.

Variety of training forms

To become a programmer, you can go another way - the creators of LAUFER CNC are ready to serve as training - distance courses. For this you need Tablet PC, netbook, smartphone or phone (mobile Internet from 1 MB/sec), with which you will be able to participate in group classes conducted by a teacher online.

In six months of training, those who have listened to the full course program at webinars will study 8 subjects, do homework and interactive exercises, and write a series of tests on the creation of the UE. They will also be taught how to make CAD drawings. They will have to take a test at a special service.

Anyone who chooses the form of independent learning (training) will be able to start at any time, without waiting for the formation of a group. It is also possible to have individual lessons with a teacher (remotely) at a time that suits both. The topics of classes and their duration are discussed in advance.

"Aerobatics" for a specialist

Sometimes a technologist-programmer is faced with very difficult tasks: to perform highly qualified work, to be able to understand drawings, to have perfect knowledge of turning and milling, and milling on CNC machines. Having a higher education (specialty - materials processing, and leading profile - mechanical engineering).

A specialist of this level must have a thorough knowledge of cad/cam; a system that is designed to automate the design process (CAD); as well as a similar version of NX (Unigraphics). This system, which is built on best technologies, in Russia it is widely used in various industrial fields. It is designed for processing workpieces with machines of any level of complexity.

Another requirement for a specialist with such qualifications is to have experience (over 3 years) on five-axis machining centers. Thanks to them, it is possible to perform processing simultaneously in five coordinates. That is why many enterprises in the mechanical engineering industry purchase machine tools, and the aerospace industry is no exception.

High precision and cutting speed are ensured by a double drive system along the Y axis. A big plus is the presence of a rotary table and 60 tool positions.

CNC systems for machine tools

As electronic and computing devices improved, microprocessor-based control modules with microcontrollers appeared in the new generation of machine tools, capable of flexibly controlling material processing processes.

Control systems are classified according to several criteria:

1. Control methods (positional, contour, universal).
2. Approaches to positioning (absolute and relative reference).
3. Type of feedback (open and closed, self-adjusting).
4. The technical level differs between systems of the 1st, 2nd and 3rd generations.
5. The number of coordinate axes (from 2 to 5).
6. The method of preparing and entering the UE.

When operating CNC equipment, they use system (utility) and control (external) programs. There was a time when companies used specially developed commands when programming their machines. To ensure equipment compatibility different brands, G-code was created - a unified program language. Among the world's recognized CNC systems are SINUMERIK, FANUC and FAGOR.

Conclusion

A programmable machine is extremely accurate and, working in various modes, can perform many different technological operations. The main thing is the availability of high-quality workpieces, competent software, serviceable and well-sharpened tools. One of the main figures in working on this equipment is the programmer, without whose participation CNC machines simply cannot work.

The progress of microelectronics, in parallel with increasing requirements for the quality of processing and flexibility in reconfiguring production, is displacing manually operated machines into the field of repair, small business and hobbies. CNC machine programming – the most important part technological support at modern enterprises.

Programming consists of specifying an interconnected sequence of commands representing a coded algorithm for the movement of working bodies, cutting tools and workpieces. The most common international standardized alphanumeric code remains ISO 7 bit. Advanced control systems support both standard code, and proprietary conversational languages.

Programming Methods

The programming process can be performed:

• Manually. A technologist compiles a program on a remote PC in text editor. Then it transfers it to the control memory via a USB flash drive, optical disk, floppy disks or through interface ports connected to a PC with a cable.
• On the CNC console (stand). Commands are entered from the keyboard and displayed on the screen. The set of icons corresponds to a list of canned cycles that can be assigned, reducing the recording volume. A number of systems ( , ) support interactive intuitive interface, where the operator forms a processing program by sequential selection.
• Automated in integrated /CAM/CAE systems. An advanced method that requires the implementation of a single electronic system at all stages of the production cycle.

The first method can be used for programming simple turning operations, processing groups of holes, milling along two coordinates without processing profile curves. The time spent is high, errors are detected on the machine.

Programming from the remote control allows you to perform all of the above, and with an interactive input language, even more complex transitions of 2.5 and 3-axis processing. The best option to adjust existing or create batch processing programs based on a “template”.

Working in CAM systems, for example: MasterCAM, SprutCam, ADEM involves obtaining a sketch, a model from CAD, interactive selection of a machine, movement limits, fixtures, tools (MI), modes, transitions and processing strategies, setting correctors. Based on this, the postprocessor converts the trajectory of the RI into a control program (CP). Virtual testing can be viewed on the monitor, eliminating obvious errors (gouges, uncut allowance, collisions with equipment), optimizing the trajectory.

Order of writing programs

Writing CNC programs consists of a sequence of actions that are the same for any method, performed by a technologist or automatically. On preparatory stage perform:

• Specifying workpiece parameters. In CAM systems: dimensions, material, hardness.
• Setting the coordinate system and zero points.
• Selecting the surfaces to be processed, calculating the number of passes for the allowance to be removed and the depth of cut (CAM offers breakdown options).

• Choice of RI.
• Setting cutting modes: feed, speed (number of revolutions) and rapid traverse speeds. CAM systems implement automatic selection of optimal ones, which are subsequently recorded in frames using the F, S functions.
• In CAM programs, a machine and a control system are selected.

At the main stage, the trajectory of the tool center is calculated, the control program describes the working and idle movements of this point. At manual way the technologist calculates the coordinates of all reference points of the contour being processed, at which the direction of the traversal changes. The movement of the RI describes a sequence of frames containing a preparatory function G, which establishes the type of movement and dimensional words (X, Y, Z, A, B, C, others), specifying movements along coordinates.

The manual presents the basics of manual programming and adjustment of CNC metal-cutting machines in small-scale conditions. serial production. The issues of compiling calculation and technological maps are considered, and fragments of control programs for CNC machines are given. elements of setting up CNC machines are presented.
Intended for students studying in the areas 150900 “Technology, equipment and automation of mechanical engineering production”. 150700 “Mechanical Engineering” and the profile “Machines and technology of highly efficient material processing processes.”

Technological preparation of production on CNC machines.
Trend modern production - «... constant update production is an objective process fundamentally connected with scientific and technological progress and interdependent by it.” Main ways to update products:
modernization of outdated models and designs:
development and production of fundamentally new, unparalleled products:
product renewal associated with changes in its consumer qualities:
updating or modernization of products related to the improvement of production methods or processes.

Intensification of the pace of product renewal is possible in production. equipped with computer numerical control (CNC) equipment.

To produce a given product at the enterprise, it is necessary to carry out technical preparation of production. Technical training production is divided into design preparation, technological preparation and scheduling. Design preparation for production includes the development of a product design with the preparation of all necessary design documentation.

TABLE OF CONTENTS
INTRODUCTION
1. BASICS OF PROGRAMMING FOR CNC MACHINES
1.2. Numeric software control equipment
1.3. Design Features technological process on CNC machines
1.4. Coordinate system and machine reference points
1.5. Control program structure
1.6. Control program format
1.7. Coding of preparatory functions
1.8. Cycle programming
1.8.1. Technological solutions in cycles
1.8.2. Cycle programming
1.9. Coding Helper Functions
1.10. Programming dimensional movements
1.10.1. Development of calculation and technological map
1.10.2. Features of the development of RTK for lathes
1.10.3. Features of the development of RTK for milling machines
1.10.4. Features of the development of RTK for drilling machines
1.10.5. Linear interpolation
1.10.6. Specifying dimensions in increments
1.10.7. Specifying dimensions in absolute values
1.10.8. Programming circular interpolation
1.11. Floating zero input
1.12. Threading
1.13. Machine status programming
1.14. Tool offset programming
1.15. Programming subroutines
1.16. Development of setup map
2. BASICS OF SETTING UP CNC MACHINES
2.1. Procedure for setting up CNC machines
2.2. Setting up CNC lathes
2.2.1. Features of setting up CNC lathes
2.2.2. Preparation, adjustment and installation of cutting and auxiliary tool
2.2.3. Requirements for cutting tools for CNC machines
2.2.4. Installation of the working parts of the machine in initial position
2.3. Setting up CNC milling machines
2.3.1. Machine zeros
2.3.2. Milling machine equipment
2.3.3. Linking the workpiece and cutting tool
2.4. Setting up multi-operational CNC machines
2.4.1. Installation of workpieces on a metal-cutting machine
2.4.2. Placing workpieces on the table
2.4.3. Securing workpieces on the table
2.4.4. Installing the workpiece in the fixture
2.4.5. Requirements for machine tools
2.4.6. Requirements for fixtures for multi-operational machines
2.4.7. Adjustable and non-adjustable devices
2.4.8. Preparation, setup and installation of cutting and auxiliary tools
2.5. Debugging the control program on the machine
2.6. Development of control programs obtained using CAD/CAM systems
2.7. Technological parameters of control program execution accuracy
3. SELF-TEST QUESTIONS
4. REFERENCES
5.APPLICATIONS
5.1. Basic symbols on CNC control panels (GOST 24505-80)
5.2. Symbols of CNC control panels (GOST 24505-80)
5.3. Additional symbols for the IR320PMF4 machine
5.4. Additional symbols for the STP220AP machine
5.5. Preparatory functions of the Mill 155
5.6. Preparatory functions of the IR320PMF4 machine
5.7. Preparatory functions of the STP220AP machine
5.8. Secondary functions machines IR320PMF4 and STP220AP.

Free download e-book V convenient format, watch and read:
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• Electrical equipment of diesel locomotives and diesel trains, Belozerov I.N., Balaev A.A., Bazhenov A.A., 2017
• Theoretical foundations of accelerated assessment and forecasting of the reliability of technical systems, Gishvarov A.S., Timashev S.A., 2012

2.1 Structure and content of the NC program

Note

The guideline for developing a part program is DIN 66025.

A (CNC/parts machining) program consists of a sequence of NC blocks (see following table). Each frame represents one processing step. Statements are written in the frame in the form of words. The last block in the execution sequence contains a special word for the end of the program: M2, M17 or M30.

Program names

Each program has its own name, which is freely chosen when creating the program, subject to the following conditions (except for the punched tape format):

The first two characters must be letters (also a letter with an underscore)

other letters, numbers

MPF100 or WELLE or

Only the first 24 characters of the program ID are shown on the CNC.

Punched tape format

File names:

File names may include characters

0...9, A...Z, a...z or _ and have a maximum length of 24 characters.

File names must have a 3-letter extension (_xxx).

Data in punched tape format can be created separately or processed in an editor. The file name stored in the CNC memory begins with "_N_".

A file in punched tape format is entered as %<имя>, "%" should be in the first column of the first line.

%_N_WELLE123_MPF = part program WELLE123 or

%Flansch3_MPF = Flansch3 part program

Further information on transferring, creating and saving part programs can be found in:

/BAD/, /BEM/ Operating Instructions for HMI Advanced, HMI Embedded chapter "Control area Program"/"Control area Services"

2.2 Language elements of a programming language

The language elements of a programming language are defined

character set with uppercase/lowercase letters and numbers

words with address and sequence of numbers

personnel and personnel structure

frame length with max. possible number of characters

sequence of words in a frame with a table of addresses and their meaning

main and auxiliary personnel

frame number

addresses with table for important addresses and explanations

addresses valid modally or in a frame

addresses with axial extension with table of extended address writing

fixed addresses with table and value data for standard installation

fixed addresses with axial extension with table and indication of value for standard installation

set addresses indicating the set address letters

predefined computational functions, as well as arithmetic, logical and comparison operators with corresponding value assignments

identifiers, e.g. variables, subroutines, code words, DIN addresses and jump marks

Fundamentals of CNC programming 2.2 Language elements of a programming language

Character set

The following symbols are available for creating NC programs:

Capital letters

A, B, C, D, E, F, G, H, I, J, K, L, M, N,(O),P, Q, R, S, T, U, V, W, X, Y, Z

In doing so, take into account:

Do not confuse the letter "O" with the number "0".

Lower case

a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z

Note Capital and lower case do not differ.

1, 2, 3, 4, 5, 6, 7, 8, 9

Special symbols

% Program start symbol (only for creating a program on an external PC)

< меньше

> more

: Main frame, end of label, linking operator

= Assignment, part of equality

/ Division, frame skip

* Multiplication

Addition

- Subtraction, negative sign

" Quotes, identification for a string of characters

" Apostrophe, identification for special numeric data: hexadecimal, binary

? Reserved

! Reserved

Fundamentals of CNC programming 2.2 Language elements of a programming language

Note Hidden special characters are treated as space characters.

CNC programs consist of blocks; frames in turn consist of words.

A CNC Language word consists of an address symbol and a digit or sequence of digits representing the arithmetic value.

The address symbol for a word is a letter. A sequence of numbers may include a sign and a decimal point, and the sign always appears between the letters of the address and the sequence of numbers. The positive sign (+) is not recorded.

Personnel and personnel structure

An NC program consists of individual blocks, a block of (several) words.

The block must contain all the data to perform the work operation, and ends with the character "LF" (LINE FEED = new line).

Fundamentals of CNC programming 2.2 Language elements of a programming language

Note

The "LF" character is not written; it is created automatically when switching lines.

Frame length

A frame can consist of max. of 512 characters (including comment and end-of-frame character

"LF").

Note Typically, the current frame display shows three frames with a max.

66 characters each. Comments are also shown. Messages are shown in a separate message window.

Sequence of words in a frame

To make the structure of the frame clearer, the words of the frame should be arranged as follows:

N10 G... X... Y... Z... F... S... T... D... M... H...

Note Some addresses can be used multiple times in one block (e.g. G..., M..., H...)

Fundamentals of CNC programming 2.2 Language elements of a programming language

Main/auxiliary frame

There are two types of frames:

main personnel and

support personnel

The main frame must contain all the words necessary to start the technological cycle from the program section starting with the main frame.

Note Main blocks can be located in both main and subprograms. The control system is not

checks whether the main frame contains all the necessary information.

Frame number

Main frames are designated by the main frame number. The main frame number consists of the symbol ":" and a positive integer (frame number). The frame number always appears at the beginning of the frame.

Note The main block numbers within the program must be unique in order to obtain

clear result when searching.

:10 D2 F200 S900 M3

Auxiliary frames are identified by the auxiliary frame number. The auxiliary block number consists of the character "N" and a positive integer (block number). The frame number always appears at the beginning of the frame.

Note The auxiliary block numbers within the program must be unique so that

get an unambiguous search result.

The sequence of frame numbers can be any, but an increasing sequence of frame numbers is recommended. You can program NC blocks without block numbers.

Fundamentals Programming Manual, Edition 10.2004, 6FC5 298-7AB00-0PP1

Fundamentals of CNC programming 2.2 Language elements of a programming language

Addresses are fixed or settable identifiers for the axes (X, Y, ...), spindle speed (S), feed (F), circle radius (CR), etc.

Example: N10 X100

Important addresses

Fundamentals of CNC programming 2.2 Language elements of a programming language

"fixed"

This address ID is available for a specific function. Machine manufacturer

"installable"

The machine manufacturer can assign a different name to these addresses via machine data.

Modal/frame-by-frame addresses

Modally valid addresses retain their significance with the programmed value until (in all subsequent blocks) a new value is programmed at the same address. Block-valid addresses only retain their significance in the block in which they were programmed. Example:

Fundamentals of CNC programming 2.2 Language elements of a programming language

Extended addresses

Extended address writing allows you to systematize a larger number of axes and spindles. The extended address consists of a digital extension or a variable identifier written in square brackets and assigned an arithmetic expression using the "=" symbol.

Extended address spelling is allowed only for the following simple addresses:

The number (index) in extended address writing for addresses M, H, S, as well as for SPOS and SPOSA can be replaced by a variable. In this case, the variable identifier is in square brackets.

Fundamentals of CNC programming 2.2 Language elements of a programming language

Fixed addresses

The following addresses are fixed:

: Main frame

Programming example: N10 G54 T9 D2

Fixed addresses with axial extension

Explanation:

When programming with axial extension, the axis to be moved is in square brackets.

Full list of all fixed established addresses can be found in the application.

Fundamentals of CNC programming 2.2 Language elements of a programming language

Settable addresses

Addresses can be specified either as an axis letter (with a numeric extension if necessary) or as a free identifier.

Note The addresses to be set must be unambiguous within the control system, i.e. one and the same

The same address identifier cannot be used for different types of addresses.

The types of addresses differ:

axial values ​​and end points

interpolation parameters

submissions

regrinding criteria

measurement

behavior of axes and spindles

Settable address letters are: A, B, C, E, I, J, K, Q, U, V, W, X, Y, Z

Note The names of the settable addresses can be changed by the user via machine data.

X1, Y30, U2, I25, E25, E1=90, …

Digital expansion has one or two positions and is always positive. Address ID:

The writing of the address can be supplemented by adding other letters. Example:

Addition

Subtraction

Multiplication

Attention: (type INT)/ (typeINT)= (typeREAL); for example, 3/4 = 0.75

Division, for variable type INT and REAL

Attention: (type INT )DIV (type INT )= (type INT ); for example, 3 DIV 4 = 0

Extracting the fractional part (for INT type only) gives the remainder of the division

INT, for example, 3 MOD 4=3

: Linking operator (y frame variables)

Comparison operators and logical operators

Fundamentals of CNC programming 2.2 Language elements of a programming language

In arithmetic expressions using parentheses you can set the processing sequence of all operators, thereby deviating from the usual rules of precedence.

Value assignments Addresses can be assigned values. The assignment of values ​​is carried out

in different ways depending on the type of address identifier.

The "=" character must be written between the address identifier and the value if

the address identifier consists of more than one letter,

a value consists of more than one constant.

The "=" character is not needed if the address identifier is a single letter and the value consists of only one constant. Signs are allowed, a separation character is allowed after the letters of the address.

Example of assigning values

Note: The digital extension must always be followed by special character "=", "(", "[", ")",

"]", "," or operator to distinguish an address identifier with a numeric extension from address letters with a value.

Identifier Words (according to DIN 66025) are supplemented with identifiers (names). These extensions have the same meaning within an NC block as words. Identifiers must be unambiguous. The same identifier cannot be used for different objects.

Identifiers can be recorded for:

variable

– system variable

– user variable

subroutines

CNC Programming Basics

code words

DIN addresses with multiple letters

jump markers

Structure

The ID consists of a maximum of 32 characters. The following symbols can be used:

letters

underscores

numbers

The first two characters must be letters or underscores, and there must be no separator characters between individual characters (see following pages).

Example: CMIRROR, CDON

Note Reserved codewords cannot be used as

identifiers. Separating characters between individual characters are not allowed.

Note Number of characters for individual identifiers

program names: 24 characters

Axis ID: 8 characters

variable identifier: 31 characters

Identifier naming rules

To avoid name overlap, the following rules are used:

All identifiers starting with “CYCLE” or “_” are reserved for cycles

All identifiers starting with “CCS” are reserved for cycles compiled by SIEMENS.

Custom compiled loops begin with "CC".

Other reservations

The "RL" identifier is reserved for conventional lathes.

CNC Programming Basics

2.2 Language elements of a programming language

Identifiers starting with "E_" are reserved for programming

Variable IDs

For variables used by the system, the first letter is replaced by the "$" symbol. This symbol cannot be used for user-defined variables.

Examples (see "List of system variables"): $P_IFRAME, $P_F

For variables with digital extension, leading zeros have no meaning (R01 corresponds to R1). Separating characters are allowed before the digital extension.

Array IDs

The same rules apply to array identifiers as to elementary variables. Addressing R variables as an array is possible.

Example: R=…

Data types

There may be hidden behind the variable numeric value(or several) or a symbol (or several), for example, an address letter.

What data type is allowed for the corresponding variable is determined when the variables are defined. For system variables and predefined variables, the type is set. The elementary variable types/data types are:

These same elementary types can be composed into arrays. At most, two-dimensional arrays are possible.

Fundamentals of CNC programming 2.2 Language elements of a programming language

Permanent

Integer constants

An integer value with or without a sign, for example as an assignment to an address Examples:

Note If for an address with a permissible entry of a decimal point after the decimal point

If more places are recorded than are allocated for this address, it is rounded up to the allocated number of places.

X0 cannot be replaced by X.

G01 X0 cannot be replaced by G01 X! Hexadecimal constants

Constants with a hexadecimal interpretation are also possible. In this case, the letters "A" to "F" serve as hexadecimal digits from 10 to 15.

Hexadecimal constants are enclosed between two apostrophes and begin with the letter "H" followed by the hexadecimal value. Separating characters between letters and numbers are allowed.

$MC_TOOL_MANAGEMENT_MASK="H3C7F";assignment of hexadecimal numbers

machine data

The maximum number of characters is limited by the range of values ​​of the integer data type.

Binary constants Constants that are interpreted binary are also possible. In this case, only the numbers “0” and “1” are used.

Binary constants are enclosed between apostrophes and begin with the letter "B" followed by the binary value. Separating characters between digits are allowed.

Fundamentals of CNC programming 2.2 Language elements of a programming language

Example machine data (see also “Advanced programming”):

Program segment

A program segment consists of one main block and several auxiliary blocks.

:10 D2 F200 S900 M3 N20 G1 X14 Y35

Skipping frames

Blocks that are not executed every time the program is executed (for example, debugging a program) may be skipped.

Frames that should be skipped are indicated by a "/" (slash) character before the frame number. Several consecutive frames may also be skipped. Statements in skipped frames are not executed, the program continues on the corresponding next, non-skipped frame.

Fundamentals of CNC programming 2.2 Language elements of a programming language

Example of skipping frames

Machine manufacturer The number of skip levels that can be used depends on the machine

indication data. Skip blocks of skip levels /0 to /9 are activated via the operator panel in the "Machine" operating area (see /BAD, BEM/ HMI Advanced/Embedded Operating Instructions), in the "Program Control" or "Adaptive Control" menu.

Note Variable program executions can also be created by using

system and user variables for conditional transitions.

Goals (tags)

By defining jump targets (labels), branches can be programmed within the program.

Label names are specified with a minimum of 2 and a maximum of 32 characters (letters, numbers, underscore). The first two characters must be letters or underscores. The label name is followed by a colon (":").

For other information, see

Literature: /PGA/, Programming Guide "Advanced Programming"

Fundamentals of CNC programming 2.2 Language elements of a programming language

Note Labels must be unique within the program.

Markers are always at the beginning of the frame. If there is a program number, the label appears immediately after the block number.

Who should be entrusted with programming CNC processing: a programmer-technologist or a machine operator?

Tooling manufacturers and other subcontractors around the world are facing two key challenges today. The first is that customers are designing products of increasingly complex shapes. Fashion trends highlight aesthetic criteria rather than the functional features of a product. In addition, complex shapes are increasingly driven by ergonomic requirements. The second problem is that despite the increasing complexity of products, the time frame from receiving an order to shipping the finished product continues to decrease. The laws of the market are such that delivery times are often even more important than the selling price. Although, of course, the customer always strives to pay less and receive the product as quickly as possible.

When a tooling company takes on a complex order and at the same time tries to significantly reduce production time, bottlenecks inevitably begin to emerge. As a rule, one of them is the CAD/CAM department, which is due to a number of objective factors. Due to the complication of the product shape, the design complexity of the prefabricated equipment increases, which, in turn, reduces the technological tolerances for its manufacture. Increasing design complexity means an increase in the number of processed surfaces, the processing of which requires time. When specifying complex CNC machining, the technologist also has to use more tools, which requires longer programming times. All this increases the “computer” calculation time required to generate tool paths (TP). Of course, the growth in computing power of computers and optimization of CAM system code have improved the situation. But in most cases, the company has no other choice but to extensively increase the number of jobs with a CAM system. However, finding an experienced technologist who knows the CAM system you are using can be quite difficult. The general trend is that experienced CNC programmers go to work for large holdings that can offer a highly qualified employee a higher salary. Therefore, it is quite difficult to increase the staff of CNC programmers. What should small companies do in this case? If a company uses a reliable CAM system with a high degree of automation in the preparation of NC, then for simple products it is possible to transfer the functions of a technologist-programmer directly to the operator of a CNC machine. Thus, part of the software program will be developed right on the shop floor.

CIMdata's 2005 CAM market survey report found that 57% of CAM systems sold were used by CNC machine programmers at their desks. 18% of users used a CAM system directly on the shop floor using CNC machines. The remaining 25% use the CAM system from time to time, depending on current circumstances. Unfortunately, the report does not contain any data on the distribution of user preferences by region. Comments from Delcam plc offices around the world indicate that the idea of ​​CNC programming on the shop floor began in North America and it was there that it became most widespread. In Europe, CNC programming on the shop floor is also becoming popular. But in Asia it’s the other way around: they prefer to program all CNC processing in a separate CAD/CAM department, remote from the workshop.

Benefits of CNC programming on the shop floor

Placing the CAM system in the workshop ensures whole line benefits. First of all, machine operators know more about the features of machining and all the machines installed in the workshop. Therefore only they can choose best mode and machining strategy (based on available tooling). Thus, CNC programming on the shop floor should improve the quality of machining.

Of course, many technologists - programmers of CNC machines began working as operators in the workshop and, only after gaining experience, moved from the workshop to the CAD/CAM department. However, such a rise in the career ladder does not mean that the CNC programmer is well aware of the capabilities and features of new tools and machines that appeared after he left the workshop. For example, modern cutting tools can operate at cutting speeds and feeds that were considered unattainable just five to seven years ago. This is just one example where a company can lose benefits by not fully utilizing the capabilities of new equipment. As practice shows, only the operator working in the workshop near the machine fully understands the capabilities and limitations of the machine and tool.

It is also important that only the operator knows the current state of the machine, tools, workpieces and technological devices (clamps). If the operator has a thorough understanding of the situation on the shop floor, planning efficiency will be higher. A CNC programmer working in a CAD/CAM department remote from the workshop does not have operational information, which can result in equipment downtime during reprogramming of CNC processing for another tool or machine.

Sometimes, for some reason, an operator needs to edit a ready-made and worked CNC program. For example, if a necessary tool is missing or broken, he can select an existing suitable alternative tool size and independently recalculate the CP without involving the CAD/CAM department. Naturally, the operator must have sufficiently high qualifications, but providing him with a certain independence and responsibility for the work performed will help improve his qualifications, interest in the final result and the prestige of the work.

The above does not mean that we should completely abandon the CAD/CAM department and entrust all its work to machine operators. The resources freed up from the CAD/CAM department should be directed to solving a very important task - quickly and accurately determining the cost of a potential order. If the manufacturer adheres to reasonable (competitive) pricing policy and tells the potential customer a specific, reasonable price much faster than his competitors, then he has every chance of receiving the order. As a rule, the customer already has an approximate idea of ​​the cost of the work, and if the offer approximately coincides with his expectations, then, most likely, he will not waste time and wait for other competitors to quote him similar prices. Participation in the preparation of a commercial proposal by the CAD/CAM department will allow us to analyze the order and reduce the likelihood that it will become unprofitable for the contractor due to underestimation of its complexity.

Requirements for a CAM system

To transfer NC preparation from the CAD/CAM department to the shop floor, it is necessary that the CAM system meets some specific requirements of the CNC machine operator.

First, operators typically do not have as much experience working with software as programmer technologists. Therefore, even such basic operations as “Copy”, “Paste” and “Cut” should be performed in the CAM system using the key combination familiar to Windows OS - this will significantly reduce the initial training period.

The second extremely important feature is that the operator must see on the screen a visualized 3D model of the processed workpiece with a processed allowance, which is automatically updated after each NC recalculation. Of course, this will also be very useful for a programmer technologist working in an office who cannot see the machine. Visualization of the processing allowance allows you to choose the optimal processing strategy and the most suitable tool in shape and size. But the operator of a CNC machine needs even more visualization of processing - this will allow him to instantly compare the part processed on the machine with a computer model. Thus, visualization of the processing in the CAM system will give the operator confidence that he will get the expected result predicted by the CAM system.

Third, the CAM system must offer wide range processing strategies with the possibility manual editing UE on any part of the trajectory. It should allow an experienced operator to do exactly what he wants, without limiting him with his capabilities. In addition, the CAM system must fully support all existing capabilities of the CNC machine, especially when it comes to programming five-axis and high-speed machining. Many CAM systems today provide a high degree of automation in the development of software, which allows you to reduce the preparation time for software and the period of mastering the software product by a new user. However, most of the trajectories calculated by such CAM systems are a compromise for a certain average type of machine and do not allow full use of the capabilities specific model machine from a single manufacturer. Therefore, the CAM system must provide the ability to fine-tune for each type of machine to achieve highest performance processing.

Fourthly, for an operator on the shop floor, the time it takes for a CAM system to generate control programs is more critical than for a technologist-programmer in a department remote from the machine. After all, when calculating a new CP, the machine may turn out to be inactive, and any downtime can undermine the operator’s reputation.

Finally, fifthly, the CAM system must have a module for checking the generated CP for the absence of cuts and collisions. Visualization of processing will also help to identify all problems before the NC is sent to an expensive machine. Simulating the operation of a programmer is especially important for five-axis machining, since an inexperienced programmer can accidentally damage an expensive machine. If a machine breaks down, the company will not only be forced to pay for repairs, but will also lose significant benefits from long-term equipment downtime. CP verification makes it possible to guarantee with a high degree of reliability that during machine operation no troubles will occur related to the correctness of the generated CP. The most advanced machining verifiers use accurate, detailed 3D models of the machine, tool and workpiece to detect any unwanted contact between the tool, the part and all machine elements. If unwanted or dangerous movements are detected, the user can manually edit the CP or use a different processing strategy.

Visualization of machining in a CAM system can also indirectly improve machining productivity. For example, during visualization, the user may see that a different position of the workpiece on the machine rotary table or the use of a different clamping device will improve machining productivity.

Shop CAD system

If there is no debate about the need and usefulness of having a CAM system in the workshop, then the advisability of having a CAD system there is not so clear.

Very often the 3D model submitted by the customer contains geometry errors. Some of them are caused by incorrect conversion of data from other CAD systems. For example, a 3D model may contain duplicate surfaces or gaps between edges, some surfaces may be lost, and sometimes the surface normal is set incorrectly. All of these shortcomings can be identified and corrected relatively easily in many CAD systems. Another, more complex type of error is often associated with the unsuitability of the model for mass production. For example, the 3D model may lack casting drafts or may contain fillet radii that are too small, preventing the mold from filling during casting. This type of error can be corrected in many hybrid CAD systems. Of course, finalization of the 3D model can be quickly completed by the operator right in the workshop. However, there is a possibility that the CAD model will receive changes that are neither fundamentally necessary nor structurally permissible. To avoid such miscalculations, it is necessary to work out a mechanism for quickly approving changes to the CAD model between the operator, the CAD/CAM department and the customer. For most companies, it would be wiser to distribute responsibilities between the CAD/CAM department and the shop so that only fully finalized and approved CAD models reach the shop, so that the CNC machine operator does not have to worry about the correct geometry of the part.

Case Study: Delphi

Global trends in the automotive industry are such that most manufacturers prefer to place as many orders as possible with their subcontractors rather than produce all the components themselves. However, Delphi (www.delphi.com), a world leader in the production of automotive electronics, on the contrary, seeks to expand own production. Thus, its Flint division (Michigan, USA) equipped its 29th production workshop with the PowerMILL CAM system and high-speed Makino machines. This allowed the company to significantly reduce the time from receiving a CAD model to shipping the finished batch.

In the 29th workshop, the development of NC for Makino machines is carried out directly by CNC machine operators, for which eight licenses for PowerMILL from Delcam plc were purchased. “As machine operators, we understand the ins and outs of the machine tool so we can produce high-quality molds,” said Jeff Johns, a CNC programmer who handles high-speed mold components. - Combination of our practical experience, Makino machines and software Delcam gives us consistently excellent results. PowerMILL will allow us to program the machining exactly the way we need it, and we have achieved huge time savings by reducing tool travel through the air and reducing tool breakage.”

High quality treated surface and absolute absence of gouges are the hallmarks of Delphi molds

“We've also never had any gouges on our parts using the PowerMILL CAM system,” adds programmer/operator Rob Bergeron. - This is extremely important for us, since the requirements for our products do not allow traces of welding repairs in the event of cuts on the working surfaces of the molds. Just one cut will mean for us that the part needs to be processed on the machine again!”

“The biggest benefit of Delcam plc's software is how quickly it can be learned,” says operations programmer Bill Jordan. - A skilled operator who already knows the CNC machine controller commands can begin developing effective NC programs in just two weeks. Each new release of PowerMILL meets the expectations of our programmers, and the success of subsequent upgrades indicates that Delcam thoroughly tests its software before it reaches the customer’s workshop.”

To the unit inside large company even more requirements are imposed than on an external subcontractor. First, the in-house division must provide a lower cost of production than any of the external competitors can offer. Secondly, the delivery time for finished products should also be shorter than that of any of the competitors. As a rule, it takes 8-12 weeks to release a new batch. But, despite such stringent requirements, workshop 29 has been operating successfully since 2002, and the volume of products it produces is steadily growing.

Competition forces workshop 29 to look for ways to reduce production costs. The reduction in production costs is achieved through automatic operation machines without the presence of operators and a significant reduction in the amount of manual finishing. “The surface processed by a tool with a rotation speed of 30 thousand rpm,
looks incredibly smooth, so we are already close to the stage where the mold can be sent straight from the machine to production without manual finishing,” explains Mr. Bergeron.

The equipment produced by the 29th workshop is intended for mass production of electromechanical products, such as housings for air purifiers, fuel level sensors, LED clusters, etc. “We know that by producing orders in-house, our the workshop is underway contrary to global trends, - comments on the situation
Mr. Jordan. “However, Makino’s high-speed machines and PowerMILL CAM system allow us to reduce production costs to an acceptable level and exceed our customer’s expectations.”

The Success of Shinyoung Precision

The use of Delcam software and the transfer of authority for NC development to the workshop where five-axis Mikron CNC machines are used allowed the well-known Korean manufacturer Shinyoung Precision mobile phones will significantly reduce order fulfillment time. Founded in 1993, Shinyoung Precision (www.shinyoung.co.kr) owns three factories and one R&D center near Seoul, the capital South Korea. Today, Shinyoung Precision, which supplies products to Motorola and LG, employs about 300 people.

Over the past five years, during which the implementation of software products family of Power Solution, the company was able to reduce the average production cycle time from 30 to 11 days. In the future, this period will probably be reduced to 9 days.

The use of CAM systems directly on the production floor began at Shinyoung Precision in 2002 and was accompanied by a transition to PowerMILL. The reason for moving CNC programming from the CAD/CAM department to the shop floor was to eliminate delays due to inconsistencies between the CAD/CAM department and production site. Only this made it possible to reduce the production cycle from 30 to 22 days! As it turned out later, the innovation improved the quality of manufactured products, since operator-programmers, based on the characteristics of specific machines, assigned more rational processing strategies and tools. In addition, the number of tool breakdowns has decreased, which also reduces production costs.

Advances in machining prompted Shinyoung Precision management to take the next step - to similarly bring EDM programming into the shop by purchasing a CAM module for EDM in PowerMILL from Delcam. This made it possible to reduce the average production cycle by another two days.

In February 2004, five-axis machines from Mikron were purchased. The combination of Mikron five-axis machines and the PowerMILL CAM system has significantly improved the quality of machined surfaces through the use of shorter (and therefore stiffer) tools.

Improving the quality of milled surfaces has allowed Shinyoung Precision to significantly reduce the amount of EDM required. Previously, it was performed first with rough electrodes, and then with finishing electrodes. The volume of material removed was quite large, which required significant time s x costs. Nowadays, rough EDM has been replaced by five-axis milling and only finishing EDM is used.

Additional savings time was obtained from the use of finishing electrodes on five-axis machines in one setup. Previously, electrodes were processed on three-axis machines in several settings, which not only took more time, but also had a negative impact on accuracy.

Instead of a conclusion

In this article, we tried to show what benefits a tool manufacturer will receive if the programming of CNC machines is entrusted to programming operators. We hope that the two given examples from practice will force adherents of CNC programming in separate CAD/CAM departments to think about the possibilities of reducing costs and increasing productivity. But don’t think that CNC programming in the shop itself is the solution to all problems. At Delphi, one of the keys to success was high-speed machining, and at Shinyoung Precision, the transition to five-axis milling. But in both cases, one of the main components was a CAM system capable of fully realizing the capabilities of the machine equipment used. Only a balanced approach, in which the set of capabilities of the equipment and the CAM system is considered together with the characteristics, will improve labor productivity and product quality.

Based on materials from Delcam plc
Translation by Konstantin Evchenko