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Испытания на стойкость к МКК (межкристаллитной коррозии) проводились по методу АМУ ГОСТ 6032-2003. После изгиба прокипяченных образцов трещин обнаружено не было. Это свидетельствует о стойкости стали к МКК, а также о том, что нанесение лазерной маркировки не спровоцировало ее образование (рис. 5).
Рис. 5. Образец после испытаний на стойкость к МКК
Была проверена стойкость маркировки к воздействию кислот, солей и щелочей. Время выдержки при комнатной температуре составило 100 часов. В водных растворах уксусной кислоты (9%), гидроксида натрия (10%) маркировка сохранилась без изменений. В водном растворе поваренной соли (10%) на маркировке произошли коррозионные процессы. Водный раствор азотной кислоты (10%) вызвал осветление маркировки, а растворы соляной и серной кислоты (10%) - поверхностное растворение металла без сохранения маркировки.
Также образец с маркировкой выдерживался в течение 3 часов в кипящей водопроводной воде. В результате эксперимента сама маркировка не поменяла свой цвет, подложка немного потемнела, считываемость кода сохранилась. Однако, после просушки образца, по границам маркировки появилась коррозия.
Для измерения микротвердости в работе использовался ПМТ-3. Микротвердость образцов составила: подложка 2637,2 МПа, код 2953,7 МПа. То есть твердость оплавленной зоны при большей мощности лазера выше.
Перед внедрением изделий с лазерной маркировкой в промышленность требуется тщательный анализ среды работы данного изделия. По результатам проделанной работы можно судить о нежелательных режимах эксплуатации изделий с лазерной маркировкой (агрессивные среды в присутствии ионов хлора, кипящая вода).
Литература
1. Бирюков В. Лазерные технологии в машиностроении // Фотоника, 2013. № 2. С. 46-53.
2. Дьюли У. Лазерная технология и анализ материалов. М.: Мир, 1986. 504 с.
3. ЛибенсонМ. Н. Взаимодействие лазерного излучения с веществом. СПб.: СПбГУ ИТМО, 2008 141 с.
Comparison of control systems Abdullabekov I.1, Anferov K.2, Khamis E.3 (Russian Federation) Сравнение систем контроля Абдуллабеков И. А.1, Aнферов К. А.2, Хамис Е. В.3 (Российская Федерация)
1 Абдуллабеков Ильяс Абдуллаевич /Abdullabekov Ilyas — студент; 2Лнферов Кирилл Алексеевич / Anferov Kirill — студент, кафедра автоматики и управления; 3Хамис Елена Валентиновна /Khamis Elena — старший преподаватель, кафедра иностранных языков в инженерно-техническом образовании, Астраханский государственный технический университет, г. Астрахань
Abstract: this article compares the two controllers used in process automation. At the beginning of the article is given a summary of the automatic control systems.
Аннотация: в данной статье сравниваются два контроллера, используемые в автоматизации технологических процессов. В начале статьи дана краткая информация о системах автоматического регулирования.
Keywords: automatic Control System, programmable logic controller, programmable Automation Controller, feedback.
Ключевые слова: система автоматического управления, программируемый логический контроллер, программируемый контроллер автоматизации, обратная связь.
Automatic Control System
An automatic control system is a preset closed-loop control system that requires no operator action. This assumes the process remains in the normal range for the control system.An automatic control system has two process variables associated with it: a controlled variable and a manipulated variable. A controlled variable is the process variable that is maintained at a specified value or within aspecified range A manipulated variable is the process variable that is acted on by the control system to maintain the controlled variable at the specified value or within the specified range [1].
PLC
A programmable logic controller (PLC) is an industrial computer control system that continuously monitors the state of input devices and makes decisions based upon a custom program to control the state of output devices.
Almost any production line, machine function, or process can be greatly enhanced using this type of control system. However, the biggest benefit in using a PLC is the ability to change and replicate the operation or process while collecting and communicating vital information.
Another advantage of a PLC system is that it is modular. That is, you can mix and match the types of Input and Output devices to best suit your application [2].
Pac
Programmable Automation Controller or PAC a relatively new name coined for small, local control systems. The name is derived largely from the popular PLC or Programmable Logic Controller. One major difference between a PLC and a PAC is the programming interface. Most PLCs are programmed in a graphical representation of coils and contacts called Ladder Logic. Most PACs are programmed in a modern programming language such as C or C++.
Since they are no longer handcuffed by the largely digital nature of Ladder Logic, PACs have become extremely popular is systems with a high percentage of analog I/O, in systems with extensive network interface requirements or in systems with direct user interaction requirements.
The primary difference between a PAC and a simple PC-based control system is that in a PAC, the «box» containing the I/O, also includes the processor and software. In fact the CPU running the system is actually built into the I/O system itself. While a typical, slaved data acquisition system is hosted by some type of general purpose PC complete with mouse, monitor and other human interface devices (HID), a Programmable Automation Controller's processor is usually dedicated to controlling the I/O system and often does not provide any direct human interface.
Physical differences between a PAC and a standard PC-based DAQ system are easily observed. However, the differences in software are equally noticeable. While most PCs operating systems for your desktop and laptop computer are large (in terms of RAM and hard drive space needed), operating systems developed for embedded systems are likely to be smaller and have been developed without all of the built-in GUIs as well as much of office equipment peripheral support.
Linux and Windows CE and Linux are likely to be the operating system under the hood of an embedded controller. Also, it is much more likely that one of these systems is running a real-time operations system such as QNX, RTX or RTAI Linux as a substantial percentage of these applications have either timing critical or high throughput requirements.
It is not uncommon for a PAC to run independent of any supervisory or otherwise outside controller. However, there is usually some link to the outside world. This may be limited to providing a simple status such as «I have no error conditions to report at this time», or it may such a tight connection that it allows an external computer take complete control while the interface between the two computers is alive. Typically, if will be in the middle where an external computer tracks system status, provides some control of key factors (e.g. temperature set point or target RPM), and/or offers the interface between the system and a human controller in charge of overall system operation.
PACs are often the heart of industrial control systems or process control applications. Programmable Automation Controllers may also be at the center of a portable data acquisition system or remote controller that allows an application to keep running even if its umbilical link to the outside world is cut.
PLC vs. PAC
While PLCs (programmable logic controllers) have been around for more than 40 years, recent advances have greatly increased their capabilities, blurring the line between a PLC and PAC (programmable automation
controller). What differences remain between these two categories? Is there a performance gap between PLCs and PACs that users should keep in mind when choosing the best solution for a particular application?
A brief bit of history can put the discussion in context. PLCs were created in the late 1960s to replace relay-based systems. Conceptually they were similar and used ladder logic that mimicked the appearance of wiring diagrams engineers used to represent physical relays and timers, and the connections among them. Early PLCs required dedicated proprietary terminals for programming, had very limited memory, and lacked remote I/O.
By the 1980s, PC-based software was introduced for programming PLCs, which had become faster and had added more features as years passed. Since then, many new technologies have been applied to PLCs, greatly expanding their capabilities on an almost continuous basis.
PACs are relatively new to the automation market, using the term coined by the market research firm ARC in 2001. Since then, there has been no specific agreement as to what differentiates a PAC from a PLC. Some users feel the term PAC is simply marketing jargon to describe highly advanced PLCs, while others believe there is a definite distinction between a PLC and a PAC. In any case, defining exactly what constitutes a PAC isn't as important as having users understand the types of applications for which each is best suited.
References
1. [Electronic resource]: Integrated Publishing. URL: http://www.tpub.com/ (дата обращения: 01.06.2016).
2. [Electronic resource]: Advanced Micro Controls inc. URL: https://www.amci.com/ (дата обращения: 01.06.2016).
Analysis of consumption of electric power the reclamative pumping stations
in the Republic of Uzbekistan Hidirov A.1, Mamasharifov M.2 (Republic of Uzbekistan) Анализ потребления электроэнергии мелиоративными насосными станциями
Республики Узбекистан Хидиров А. А.1, Мамашарифов М. А.2 (Республика Узбекистан)
1Хидиров Абдумалик Абдувохидович / Hidirov Аbdumalik — преподаватель; 2Мамашарифов Мансур Алижонович /MamasharifovMansur — студент, кафедра гидравлики и гидроэнергетики, Ташкентский государственный технический университет им. Абу Райхана Беруни, г. Ташкент, Республика Узбекистан
Abstract: in this article questions of energy consumption by pump stations of the Republic of Uzbekistan are considered and it is given general information about the operated pump stations and electric motors. Аннотация: в данной статье рассмотрены вопросы энергопотребления насосными станциями Республики Узбекистан, и даются общие сведения об эксплуатировании насосных станций и электрических двигателей.
Keywords: pump stations, electric motors, melioration, electric power, power, machine irrigation, area, pressure head pipeline, consumption, energy losses.
Ключевые слова: насосные станции, электрические двигатели, мелиорация, электроэнергия, мощность, машинное орошение, площадь, напорный трубопровод, потребление, потери энергии.
If to examine machine irrigation on the whole, then on results our researches it is possible to do next conclusion, weighted average set power of pumps, on 1 ha of machine irrigation in Republic there are 2,1 thousands kW. And in the areas of the Fergana.
