COMPUTER AIDED DRAWING
6 credits during the 1st year of 10375 CHEMICAL AND PROCESSES ENGINEERING (L-9) GENOVA
The course is about technical drawing assisted by a computer and related standards.
The course aims at:
- providing the basic instruments for representing the shape of a mechanical piece (with hand made sketches, too)
- offering the fundamentals for the definition of the functional features of a part
- illustrating the different joining elements with related criteria
- giving students the essential learning about a 2D CAD system (to be used for drawings)
AIMS AND LEARNING OUTCOMES
The lectures will allow the student to learn the general aspects and framework of the design sector with particular regard to the representation methodologies of real objects through orthogonal projections according to the European ISO method with the use of sections and the indication of quotas, dimensional tolerances, geometric and microgeometric tolerances.
In addition, some topics of particular interest to the industrial engineer will be examined, such as threaded connections, removable connections and permanent connections.
The class exercises will aim to explain the commands for the use of CAD software for the realisation of A4 tables in which a mechanical piece is represented according to European orthogonal projections. In the classroom are assigned exercises that are carried out by the students under the guidance and supervision of the teacher.
In order to facilitate the learning of the methods of representation of 2D tables to the students, grouped in pairs, themes are assigned that they develop independently. The idea is to take advantage of learn by doing and learn by trial and error. The teacher guides and assists the students without interfering with their reasoning and then asks the students to show the result to the whole class. The teacher then highlights and explains the errors and corrects them in real time.
At the end of the course, thanks to lectures, exercises and personal study. the student will be able to know and apply the method of orthogonal projections for the representation of objects, will be able to quote in an appropriate and unambiguous way and designate the dimensional, geometric and microgeometric tolerances with ISO symbols. He/she will have acquired knowledge of the terminology and basic rules for industrial technical design and will be able to identify tolerance positions and intervals suitable for the most frequent shaft-hole couplings. He/she will have learned the logic of tolerances and will be able to interpret its meaning and to indicate it according to ISO standards. He/she will have acquired knowledge and mastery of the commands for the creation of graphic primitives, their manipulation and modification and for the designation of dimensions, tolerances and machining in the CAD environment through which the two-dimensional A4 tables will be created.
Lessons and exercises in computer room.
Standardisation: international and national standards. Standard for technical drawing. Drawing types. Shape and size representation of a mechanical part: the graphic model. Hand-made sketches. Orthogonal projections, sections, dimensioning (complying the ISO standards). Overview on axonometric and slanted views. Summary on basic mechanical components.
Manufacturing tolerancing: dimensional, geometrical, surface tolerancing.
Non-permanent joining parts (threaded items, centering elements) and stable joining parts.
Guidelines on the elements shape depending on the manufacturing process and the material used.
Computer graphics. The digital mock-up. 2D modeling. Details on the SW for technical graphics. Rastering and vectoring of manual drafts.
A. Chirone, S. Tornincasa, “Disegno tecnico industriale”, vol. 1 e 2.
Additional documents are available on Aulaweb.
Ricevimento: The teacher is available for the students at the end of each lesson.
ROBERTO RAZZOLI (President)
Lessons and exercises in computer room.
According to the lessons scheduling of the Polytechnic School.
The exam is divided into 2 tests:
A graphical computer test, which involves the execution of a constructive design using the 2D CAD MICROSTATION v8i. The graphic test takes place in the computer room (duration of the test: 2 hours) and the result of the test must be ≥ 18/30.
An oral test, which includes an assessment of the theoretical knowledge indicated in the course program.
N.B. The written test, if sufficient, is valid for the whole solar year. The oral exam can be taken in any official appeal.
Application for the graphic test
It is mandatory to book using the online mode (from the University portal services to students), AT LEAST 5 DAYS BEFORE the start of the test.
Given the limited capacity of the computer lab, one group is planned in the morning and a second one in the afternoon. These groups foresee a max. of 35 people.
If the total number exceeds 70, a further date will be set.
Within the assigned term, the drawing must be printed and the file copied to the Classroom - Delivery Unit folder.
It is possible to consult books and / or manuals.
The results will be announced on Aulaweb.
The oral examination if not passed (or rejected) does not cancel the written test. The positive results obtained in the graphic tests are valid for the whole exam session (calendar year).
The final grade is the average of the oral test and written test score.
Files containing the sheet squaring for A4 and A3 formats and the Microstation seed file settings are available on Aulaweb.
Upon delivery of the written test, the evaluation of any previous test is lost.
Registration for the oral test
After the publication of the results of the written test it is possible to register for the oral exam, using the web-based booking tool. Each student enrolled in the forum will receive an email alert, with the day and time of the oral test.
The examination procedures, its preparation and the degree of deepining of each topic will be illustrated during the lessons and reported on Aulaweb.
The written examination consists in the realization of a 2D table with dimensions and tolerances of a mechanical part of which a three-dimensional representation is provided. The student must be able to represent the proposed object unambiguously, maintaining its proportions, according to the European method of orthogonal projections; must provide the minimum number of views necessary to guarantee the workable realization of the piece; he or she will have to arrange the dimensions in sufficient and not redundant manner and to indicate the tolerances according to the required specifications in the examination text. He or she must be able to use the appropriate styles and line weights; must be able to designate a coupling in the hole-basis or shaft-basis system.
The oral examination will focus on the topics covered during the lectures and have the purpose of assessing not only if the student has reached an adequate level of knowledge, but also if he or she has acquired the ability to deal with logical problems that will be posed during the exam.
The student will be asked to illustrate theories and solve problems: in relation to these it will be evaluated the clarity of exposition, the appropriateness of the used terminology and the methodological approach oriented to manufacturability, interpreting and formulating prescriptions and principles related to the description of parts in a unique, unambiguous and not redundant way.