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3D-designing for the design organisation approaches: expenses and benefits
The purpose of this article – to help the companies still using 2D, to solve: whether has for them sense to translate a part (or the majority) design works on 3D-methods. In it the question on also is discussed how to justify the means spent at transition to 3D-designing if such decision is accepted.          

Strangely enough, many companies have till now doubts – to pass or not to 3D-methods and systems CAD. The 2D-automated designing was used in some firms throughout 10-20 years. Very many companies have developed own user applications for automation of various functions of 2D-plotting. Some appendices, such as systems of working out of electric schemes, – traditionally 2D, so 3D-systems cannot replace completely all.

Let's consider transition to 3D.

One of the reasons of slow transition from 2D to 3D consists in complexity of this step. After all the enterprise is in conditions of operating manufacture when it is impossible to spend instant replacement of the software as investments, personnel conversion training, reorganisation of business processes, change of psychology of designers for this purpose are required. How it is necessary to organise the given process? Suppliers and analysts offer a number of recommendations.

It is not necessary to forget that introduction of 3D-systems usually attracts changes in the work organisation at the enterprise. Though some suppliers CAD assure that transition on 3D does not demand changes of business processes, the best results those who brings improvements reach. So, according to research Aberdeen, the advanced companies arrive. Trying to squeeze out a maximum from 3D, they parallelize designing process, involving in it technologists, testers, estimator and other experts and by that reduce expenses for working out of products and accelerate their release in sale.

But to achieve it it is uneasy. According to some experts, difficulties of transition on 3D are connected not with complexity of the product or its high cost, and first of all with change of the traditional approach to work of design and technology divisions, that is with change of rules of work of the enterprise. It is a problem more likely organizational, rather than technical. Unfortunately, heads often do not understand that, having spent certain means on 3D-CAD, it is necessary to provide organizational reorganisation, to reflect on introduction of electronic document circulation, to change an order of the statement of documents, to make other changes. In other words, 3D it is impossible to take advantage of advantages without competent introduction.

At first it is recommended to realise the pilot project to understand, what changes should be brought in business processes and the work organisation at the enterprise.

Here experts advise to customers not to pursue cheapness and to take advantage of paid introduction. Certainly, it is possible to study software under the documentation, however such “economy” in practice will turn back time losses, decrease in quality of training and introduction as in this case the customer cannot take advantage of experience for a long time the supplier who has mastered the system.

Besides, transition process is desirable be not to forcing, and to carry out gradually though and not to stretch indefinitely.

Planning transition on 3D, it is necessary to pay attention to a management question the design data. After all ability of 3D-model to store weight of the information on a product has both positive, and negative sides. Uneasy to operate weight of the data which have been written down in such model. Not casually 39% of respondents Aberdeen have noted complexity of this process. The most successful enterprises apply possibilities of control systems of the data (storage of files, search and repeated use of the information), than the companies with an efficiency average level much more actively. But the main thing, analysts, underline “leaders” realise functions of management by product configurations. As a rule, 3D-CAD create separate files for each detail and for all assemblage. To users uneasy happens to understand with versions of these files and with interrelations between them, especially so far as concerns the big assemblage including over hundred of elements. Help them control systems of the data which usually contain the special functions relieving designers from handwork with files can.

Let's consider 3D-designing process.

Processes 3D – and 2D-designing essentially differ. At designing in 2D drawings are the main documents defining a design of each detail and reflecting how these details should be collected. These drawings can be developed both on a drawing board, and by means of CAD-systems (such as AutoCAD, CADAM, Medusa or ME-10), as a matter of fact too being an equivalent of a drawing board.

The basic inconvenience of methods of 2D-designing consists that under drawings frequently it is difficult to imagine as the product really looks in space. Therefore designers are sometimes compelled to accompany drawings real prototypes. The first let out product often serves in mechanical engineering as a prototype or even the first party. In drawings, no less than the errors caused by wrong interpretation of drawings, it is necessary to correct errors on a real product – process which can be not only slow, but also expensive.

On the contrary, 3D-systems of solid-state modelling create spatial model of a product before any drawings or pre-production models will be made. The basic document in this case is not the drawing, and computer 3D-model.

3D-models made in Pro/E, can help the designer with check of correctness of the sizes before pre-production models


3D-models can be used for the various purposes, such as:
- the analysis of pressure, movings, fluctuations, flows or heat transfers;
- preparation of operating programs for milling, drilling, punching or laser are sharp on machine tools with CNC;
- preparation of spatial images of a product for engineering specifications and instructions on assemblage;
- quality assurance of products by means of laser measuring devices, optical scanners or coordinate measuring cars;
- creation of physical samples by methods of fast prototyping;
- creation of specifications for estimation of cost, purchases and planning of resources of manufacture.

For the help to workers and managers in 3D-system can be received and drawings. To generate them from 3D-model much faster and is easier, than to create manually or even with the help 2D CAD. Errors in drawings, usual at 2D-designing, cannot appear at creation of drawing kinds from unequivocally certain model of a product. Besides, all changes in drawings at 3D-designing use can be made much faster as any change of the basic 3D-model will absolutely precisely be reflected in all drawing kinds.

Application 3D CAD-systems for designing of products from sheet materials is especially effective. The 3D-model generated from a sheet material can be used in 3D-cborke for check of its correctness. Then the CAD-system can automatically create development of a detail which is useful both for working drawings, and at creation of the operating program for a press with CNC.

3D-models and for fast creation of photorealistic images of a product which can be used for commercial presentations or for discussion with marketing department are irreplaceable. Having received 2D-drawings, the artist should begin with the pure screen or a sheet of paper. Available in 3D CAD-systems of function of rendering allow artists to use geometry of already existing models of a product. For reception of the finished image it is necessary to pick up only desirable structures of a surface, light effects and a background. If the product geometry changes further on image updating some minutes is required. Working with 2D-system or c paper drawings, drawing should be created anew after each essential change in the project.

In this example the stream of energy and temperature distribution at cooling of the detail created in CATIA V5, are modelled by means of system Visual Nastran V5i


Now on sale a lot of 3D-CAD. And though the basic advantages of 3D-technology are inherent in all of them, they differ on features, to ways of introduction, the user interface and, of course, to cost. Therefore the choice depends on concrete requirements of the enterprise.

Let's consider economic gains from 3D.

3D-modelling became the standard method by working out of products and systems in automobile and space branches as it gives convincing economic benefit. At designing in 3D errors can be found and corrected before the product will reach manufacture. Early diagnosing on the computer of such problems as the wrong sizes, the crossings of details inaccessible to service components, knots which cannot be collected, – all it considerably reduces the general cycle of designing and, hence, reduces its cost.

Application of the same ready 3D-models in systems of engineering calculations, preparations of operating programs for machine tools with CNC both quality assurance reduces time and cost of the decision of these problems. It does a product by more economic at simultaneous increase in its reliability and efficiency. Besides, 3D-model presence reduces expenses for working out of drawings at the expense of automation of process of creation of kinds and reduction of quantity of cuts and sections which would be necessary at purely 2D-approach.

First of all, it is necessary to define, whether it is necessary to take such step in general. After all investments make sense only when the received benefit will justify expenses. If, let us assume, enterprise production not often is exposed to changes, can be completely reflected by means of two-three drawings, that does not demand engineering calculations or creation of programs for machine tools with CNC, probably, the 3D-system at all is not required. According to experts, it is not necessary to pass on 3D only for the sake of simplification of preparation of drawings as it hardly will bring an economic gain.

Unfortunately, to add these empirical estimations with more exact data difficultly. Besides the advantages received from introduction 3D, in strong degree depend on specificity of the enterprise and other conditions. According to some experts, creation of 3D-environment for through management of designing and manufacturing processes allows to reduce essentially quantity of natural tests, time of manufacturing of production and marriage volume that provides notable economic benefit already in uses of new technology first half a year.

As to investments into new computers they pay off at the expense of evolved labour productivity.

Let's consider a competition as stimulus of transition on 3D.

Now, when the market economy develops, and the competition becomes more rigid, the enterprises should introduce more actively a new information technology, to pass to modern ways of designing, in particular on 3D-CAD.

One of the main results of introduction of 3D-systems is acceleration of release of new products in sale. It is known that the company which the first begins deliveries of innovative production, grasps 40-70% of the market, leaving contenders far behind. And if to recollect improvement of quality and design characteristics of let out production, about reduction of quantity of the natural tests, leading to economy on pre-production models, and sharp reduction of volume of marriage in shops it becomes clear why application 3D-CAD conducts to increase of competitiveness of the enterprise.

Value of this advantage increases now when our country will enter in World Trade Organization since January, 1st, 2010 even more. After all, as it is known, after occurrence of Russia in this organisation our enterprises will be compelled to work in the conditions of a real competition. They should raise efficiency of the activity and then 3D-CAD will turn from simply useful tool to irreplaceable means without which it is difficult to survive in the market.

Let's consider expenses for introduction of methods of 3D-designing.

The majority 3D CAD-systems is used by so-called solid-state computer models. These are such systems, as CATIA V5, Pro/ENGINEER, Unigraphics NX, SolidWorks, Solid Edge, Autodesk Inventor, CoCreate Solid Designer, CADKEY Workshop, VX CAD (were Varimetrix).

Distinctions between these systems of solid-state modelling and older systems of type AutoCAD have been washed a little away by that fact that 2D-functions have been strengthened subsequently by possibilities of frame, superficial and solid-state 3D-modelling. However, despite these improvements, not many companies could introduce successfully 3D-designing methods, using the systems originally created for working out of drawings in the late seventies and the beginning of 80th years.

The most successful designers working in 3D, apply more modern software developed in the late eighties and in the nineties. To those companies which lean till now, mainly, against 2D-systems, almost for certain it is necessary to put means in new software, to modernise workstations and to carry out personnel training to exploit technology of 3D-modelling. But even after training will be finished, months if not years, to gain experience in 3D-modelling be required to designers. Right after introductions of new methods it is necessary to expect and plan some decline of productivity.

Some companies, probably, will face also necessity personnel updatings. Not all engineers can cope with 3D-modelling. Expenses for search and employment of new people can be quite comparable with cost hardware and the software, especially for inexpensive systems.

For a complete description of the form of a difficult cast detail it is required two sheets of drawings and 8 kinds. At 3D-model change all kinds are updated within several seconds


To put means in 3D CAD-systems to manufacturers it makes sense only in the event that benefits from their introduction will justify expenses. For an estimation of possible benefits it is recommended to answer following questions:
- How many means are spent for corrections of drawings in the course of design change?
- What cost of the spoilage in production caused by wrong or ambiguous drawings?
- Whether expenses on a product (including while in service) because of the inadequate or excessively simplified calculations of a design increase?
- What cost of alterations of a pre-production model and equipment for its manufacture, caused by the changes made after the beginning of deliveries?
- Your engineers could create more good products if they had possibility to give to prospective clients pre-production models in shorter terms?
- Whether less than the subsequent changes did the personnel of department of marketing if had pre-production models and 3D-models already at the initial stage of working out of a product?
- Suppliers of equipment could accelerate manufacturing if your company gave them 3D-models instead of drawings?
- Whether your clients that your firm conducted designing in 3D wish or gave 3D CAD-models of products and knots in addition to pre-production models?
- How many money your company could save, using 3D-models for quality assurance?
- Whether presence spatial and blown up kinds received from 3D-models can, to save time for preparation of engineering specifications and descriptions?

Economy definition on each of the mentioned points – a challenge which demands reception of the information from various departments. Each company is unique, and no means always it will be possible to receive economy absolutely at all points.

If, for example, production of your company seldom enough is exposed to changes if it can be completely reflected by means of two-three drawing kinds, does not demand CAE-calculations, automation of quality assurance or fast prototyping, – is possible that 3D CAD and it is not required to you.

Besides, despite perfection of the user interface, 3D-system remain difficult enough. The designer can spend many hours, trying to understand, why it is not possible to connect two constructive elements or why the system cannot construct physically possible detail. The working costs with this difficult and not always the reliable software should be compensated by benefits from 3D-models which it creates.

Some experienced users of 2D-systems assert what faster make the drawing in this system they can, than by means of 3D-methods. Really, in certain cases faster to make the drawing a pencil, than to build 3D-model. Transition to use of 3D-systems seldom can be justified only convenience of preparation of drawings. If your company cannot take any other economic gains from 3D-designing, probably, it is better to it to remain on 2D.

It is obvious that in due course CAD-systems will become more and more convenient and simple in use. Reduction of time of development will reduce expenses and the risks connected with transition to methods of 3D-designing.


Sources:
1. Whether it is necessary to pass on 3D?//CAD/CAM/CAE Observer, #4 (17), 2004 [http://www.cadcamcae.lv/hot/3d-perehod_n1 7_p04.htm]
2. Goretkina E. What CAD system we choose: 2D or 3D?//PC Week, #19 (577), 2007 [http://www.pcweek.ru/themes/detail.php?ID=82569&THEME_ID=13893]
3. Kazakov M. Switching to a 3D-design – the realised necessity//CAD and a drawing, #7, 2006 [http://www.CAD.ru/article.aspx?id=16189&iid=760]

The author: Челябэнергопроект
Date: 07/22/2009

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