The author's abstract
The theme of master's degree work: –
"Creation of the checking and management of operations of pinopoliuritanu system ".
General characteristic of work
Introduction
The role of polymers in modern technics, to be exact in all fields of activity of the person, is very great.
Not without reason 20 century named a century of polymers. Materials which basis is made with polymers concern to plastic.
Polymers have received a wide circulation for the short period practically in all areas of the industry and construction.
Urgency of a theme
Questions of mathematical modelling of processes of polymerization are shined in the literature and theories of calculation
molecular and above the molecular structure of polymers defining their complex physicomechanical and rheological of properties
are realized in practice not in that degree, as processes of reception of low-molecular substances that is connected with
insufficient development of physics -molecular bases of these complex processes. Work on modelling processes demands the certain
ordering of data under the mathematical description, including numerical values of constants, the exact description of
conditions, etc. the Degree of a detail of such models depends essentially on their purpose and restrictions of area of use.
At construction of mathematical descriptions can be used as "theoretical", determined and stochastic, and floor empirical
models. The problem of construction of adequate model represents not that other, as a problem of a choice - among set competing
- the model in the best way reflecting experimental data. Thus the opportunity of existence of some other model more detailed
reflecting the mechanism of process and, hence, by possessing greater descriptive force is never excluded.
Purpose of work
The purpose
masters works is creation of an electronic control system by technological process of manufacture rigid foaming
polyurethan(ППУ).
The given electronic system will allow to supervise parameters of process of manufacture foaming ППУ, to diagnose a technical
condition of the basic units, to carry out protectively-blocking functions, and also to conduct the dispatching account of
consumption of raw material and let out production
The developed maintenance masters works
Introduction
1. The analysis of a condition of an investigated question.
1.1. The analysis of existing systems of manufacture polyurethane.
1.2. The purposes and research problems.
2. Development of mathematical model of technological process.
2.1. Development of mathematical model of planning.
2.1.1. A choice and a substantiation of a method of planning.
2.2. Practical application of mathematical model.
3. Testing the developed mathematical model and the analysis of results.
4. Development of an electronic control system by technological process of manufacture polyurethana.
4.1. The requirement to system as a whole.
4.1.1. To the requirement to structure and functioning of
system.
4.1.2. The requirement to safety of the information at failures.
4.2. The requirement to the functions which are carried out by system.
4.3. The requirement to kinds maintenance.
4.3.1. The requirement to a supply with information.
4.3.2. The requirement to the software.
4.3.3. The requirement to technical maintenance.
4.3.4. The requirement to a software.
5. Interaction of the developed system with other systems.
Conclusions about the done work.
The list of used sources.
Expected results and degree of their novelty
Strict control after the exact observance of all of parameters of technological process is instrumental in the receipt of ППУ of high quality.
The strict control over exact observance of all parameters of technological process promotes reception ППУ of high quality.
For each composition ППУ the optimum technological mode of foaming and a separate compounding on initial components should be
fulfilled.
Poor-quality mixture of initial components can lead to formation structures PPU, to occurrence of fragility and sometimes to
falling off of foam; excessively long mixture reduces .
With use of computer technics during formations there is an opportunity precisely to set, supervise and adjust программно
following technological parameters: temperature of initial components, the heat-carrier; pressure in account capacities and a
mixing head; duration of separate technological and auxiliary operations; mass charges of components, their parity; a level
filling capacitor devices.
At formation ППУ it is difficult to achieve uniform density of a filled in composition owing to condensation ППУ on a surface
and edges of the form. On these sites of a cell turn out instead of spherical extended in a direction of foaming.
The analysis of an investigated question on approved to a theme
Manufacture
ППУ in conditions of Joint-Stock Company " NORD " is made on the installation completed and put by Italian firm " Cannon " in
2001. The developer of technological process and the manufacturer of the capital equipment are firms " Cannon " and "Afros".
Installation consists of two technological lines: with manual injection raw material in forms and with automatic. The basic
process equipment - the making foam machine of model "Cannon" series A-System 100, the maximal productivity - 90 kg/mines.
Process of manufacture foaming ППУ on the given installation has following sequence: components And, In dosing pumps from
storehouses on pipelines injecting in corresponding account capacities of the machine of foaming. Pumps are translated with
recirculating on filling of account capacities by switching locking the armature located directly at account capacities.
Filling of account capacities is supervised on gauge glasses. On the main control panel at a maximum level in account
capacities the light signal system works. After filling pumps are switched in a mode raw material in storehouses, and in
account capacities drained air pressure up to 0,4 МПа (4кгс/sm2) moves. Pressure in capacities is supervised visually on
manometers.
After filling raw material thermostatically up to temperature 20-220С. The temperature is adjusted automatically and supervised
by devices TERMOTRONIC.
Productivity of dosing pumps is established by means of limbic on each component according to the set mass parity of components.
Buttons of inclusion and deenergizing of dosing pumps are located on an electrocontrol panel.
On the main control panel light digital indication supervises volumetric productivity of dosing pumps on each component and a
volumetric parity of components And, Century Volumetric quantity of the components submitted to 1 second, in view of density,
is recalculated in mass and then the mass parity is defined.
Proceeding from volume of the forms, the established productivity of dosing pumps and the demanded seeming density of a product,
the volume injection for each form pays off and is established manually on the corresponding indicator.
Pouring in the form occurs on pressing button " Заливка " a control panel. After filling the form quickly close a cover and
densely close. The filled in forms are maintained within 15-20 minutes. After time of endurance of the form open manually or
are automatically disconnected also a product it is cautiously taken.
For ripening a product maintain in a ventilated premise within 24 hours at a room temperature. During ripening there is a
final hardening a material, replacement of dioxide of carbon in cells on air.
The list of used sources.
1. Любартович С.А., Морозов Ю.Л., Третьяков О.Б. Реакционное формование полиуретанов. - М.: Химия, 1990. -288с.
2. Булатов Г.А. Полиуретаны в современной технике. -М., Машиностроение, 1983. -272с.
3. Булатов Г.А. Пенополиуретаны в машиностроении и строительстве. -М., Машиностроение, 1978. -183с.
4. Саундерс Дж. Х., Фриш К.К. Химия полиуретанов: Пер. с англ./Под ред. Энтелиса С.Г. -М.: Химия, 1968. -470с.
5. Домброу Б.А. Полиуретаны: Пер. с англ./Под ред. Благонравовой А.А. -М.: Госхимиздат, 1961. -151с.
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