New CADD system facilitates project design 

As part of its continuing effort to contain its clients’
costs, BATEMAN has implemented a third generation
CAD (computer assisted draughting) system aimed at
significantly reducing the man-hours required by the
drawing office. In most engineering design projects,
the drawing office is the largest user of man-hours.

The new system has advanced 3D capabilities and is designed to model plant components, assemble the components and to produce 2D engineering detail drawings. The visualisation and understanding of the design is facilitated because all parts and components of the plant are fully rendered on-screen. A built-in document-management function controls document routing, maintenance and revisions. Detailed drawings can be saved in other formats (e.g. AutoCAD) and spreadsheets and word-processing documents can be directly imported.

The system utilises STREAM technology which, by means of artificial intelligence, boosts productivity and greatly reduces the risk of error. The system is used to produce plant block models to give clients an early 3D virtual-reality view of the project – before too many design man-hours have been spent. Then a plant conceptual model is produced, effectively a basic model of the plant or building, which includes all major equipment and steelwork needed for accurate pricing and plotting the footprint. The third stage is the detailed design model from which the platework detail drawings, mechanical, structural and piping general arrangements and piping detail drawings including isometrics are produced.

The system also performs interface checks between the mechanical, piping, structural, electrical and instrumentation racking – saving costs on site by minimising clashes arising out of the designs of these respective disciplines.

The envisaged savings on draughting man-hours will take some time to achieve, as the system requires a comprehensive library of plant equipment, piping and structural steel items. This will be
assembled progressively from project to project. From the outset, however, the system will produce better designs with a higher quality of drawings and will produce the materials take-off, specifically in respect of piping, at a much earlier stage of the design.

BATEMAN has considerable experience in the use of CAD in the design of process plants. This started with 2D CAD programs, which eventually produced small savings, but the drawings generally needed more checking than those produced on boards. The next step was 3D CAD, which promised major savings in man-hours, but this was difficult to achieve consistently because the programs were not user friendly and the hard- and software tended to crash at inopportune moments.

None-the-less, BATEMAN pioneered several major projects using 3D CAD, including the Impala platinum metals refinery, the Hartley flotation plant and the Atomic Energy Corporation’s PTFE pilot plant. The latter programs are capable of producing 2D drawings with good man-hour averages. The new system has advanced capabilities, proven stability and is easy to use with the learning curve being as short as three weeks after initial training. To date BATEMAN has used this system on a number of current projects.

For example:

a conceptual view of a proposed platinum-metals process plant was prepared for a client with a detailed 3D model of the flotation plant which included 300 detailed piping drawings;

a block plan was developed for a platinum refinery with 3D conceptual models to produce a 10 % definitive cost estimate (DCE);  3D conceptual models and 10 % DCEs were prepared of flotation and dense media separation plants; and

In-house detailed fabrication drawings of a machine assembly for an experimental grease table were produced.

More information may be obtained from Vernon Cockcroft, Drawing Office Manager, at vcockcroft@bmi.co.za or Peter Breddy, CADD Manager, at pbreddy@bmi.co.za.

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