Product/Service

3D Piping Software Cuts Design And Build Time By 25%

Chematur Engineering has cut time needed to design and build major chemical projects by 25% by switching from 2D to 3D design methodology...

By Thomas Stutterheim, Peter Olausson and Hakan Anderson, Chematur Engineering AB Karlskoga, Sweden

Chematur Engineering has cut time needed to design and build major chemical projects by 25% by switching from 2D to 3D design methodology. The key to these savings was switching to a 3D-design process that allows the designers to model the plant once and then quickly generate orthographic and isometric drawings directly from the original model. The manufacturing cycle was shortened because the 3D drawings are easier to understand, more consistent and require fewer changes.

Chematur Engineering is a group of engineering companies whose main activities are marketing of process know how and supply of chemical plants for the production of explosives and propellants, isocyanates, nitroaromates, ethanol and derivatives, pharmaceuticals, solvent absorption and recovery, VOC abatement, nitric acid, fertilizers and hydrogen peroxide. Proprietary technology and license agreements with major chemical companies make it possible to provide a complete chemical process program. The company has subsidiaries in Atlanta, GA, USA; Windsor, UK; an affiliate in Bombay, India, and a sales office in Hong Kong.

Chematur first began using 2D computer-aided design in 1984 when it bought an Intergraph IGDS and plant design system. This system was capable of 3D design, and Chematur used it once or twice for that purpose in the 1980s but the company's managers decided at that time that the technology wasn't developed to the point that it would be practical. Around 1990, the company switched to MicroStation, the Intergraph/Bentley PC-based design, using the 2D design capabilities. A few years later, managers decided that the time had come to switch to 3D and evaluated three different systems.

The decision was made to install the Omni Series from Rebis, (Walnut Creek, CA), for several reasons. Perhaps the most important was price. The Omni-Series is the only one of the three systems evaluated that runs on PCs rather than Unix workstations. Most of the designers using the system already had PCs. As a result, the cost, including both software and hardware, was only about 1/5 of the other systems that were evaluated. Despite that fact, its performance was entirely competitive with the other, Unix-based systems. Purchasing a PC-based system also eliminated the difficult task of administering a Unix system and made it possible to run desktop applications on the same system. Chematur started with four piping seats and two equipment seats.

It's important to note that the Omni-Series runs on top of MicroStation, using the Intergraph/Bentley product as its CAD engine. The user interface closely matches MicroStation as well. This made it very easy for operators who had at that point extensive MicroStation experience to learn the program. Within two weeks, they were routing pipes and building 3D models. In a few more weeks, they were operating the system at full speed, considerably faster than they were able to produce in 2D.

As with the traditional 2D process, the piping engineer starts with the P&ID which defines the number, material, dimensional specifications and media code (contents) of each pipe. The piping engineer also receives equipment layouts that provide guides to placement of each piping segment. The piping engineer begins working in the plan view and locates each piece of equipment. Then the engineer locates the ends of each piping segment either by typing in coordinates or clicking with a mouse. Rather than simply entering elevation data on the 2D drawing, the elevation becomes an integral part of the 3D model. Utilizing this third dimension allows the model to be viewed from any view or rotation angle.

An automated feature of the software places a full 3D pipe in the position that the engineer has defined. The centerline of the pipe is dressed in a cylinder with proper dimensions taken from the specifications database. The software also writes to the project database each of the components that have been used in the project. The result of this process is a 3D model that can be used later to automatically create whatever plan views, sections, ISOs, installation drawings and perspective views are required. ISOs produced by this approach have elevations and dimensions tagged and located, and materials for purchasing clearly called out. All of these drawings are generated from the same 3D model so that, after the model has been checked, they are certain to be correct. Any changes to the model only have to be made once and they will be reflected in any future drawings produced from it.

Figures 1 and 2 show examples of Chematur Engineering's work with the OMNI SERIES system. Chematur's manufacturing team found it much easier to visualize piping runs depicted in the 3D format.

Using the conventional approach, every drawing has to be gone over with a fine-tooth comb because each drawing is created from scratch. Chematur created specification objects for many of their own pumps and tanks, pipe supports, HVAC systems, rectangular and circular ducts, cable ladders, and many other similar items. A key advantage of using the PC-based software on "smaller" projects is that setting up specifications can be a faster process. Required specifications for PolyAD, a VOC-abatement facility, utilized the client specifications, which included client sizes, valve types, piping material specifications, etc. Setting up these specifications in Omni-Series took only about eight to 10 h per specification. These specifications handle aspects such as diameters, lengths, descriptions, component types, etc.

The company's systems people also wrote their own specifications generator using a Paradox application. This program makes it possible to scroll through the database and view a picture of the component with a table below it listing crucial dimensions. This database also includes the all the information needed for the Omni-Series database. The ability to view this information before inserting a component into the drawing makes it nearly impossible to make a mistake. The model database is used to produce bills of materials for purchasing. The information in the database goes directly into the model and from there to the bill of materials without the need for retyping, eliminating the possibility of errors.

The advantages of the new 3D drawing methodology go far beyond a 25% reduction in piping engineering time. The quality of drawing is also improved because consistency between plan drawings, sections, ISOs, perspectives, valve lists and bills of materials is assured. In very early design stages, it is possible to determine the operability of the approach. The photorealistic nature of the model makes it seem as if the operator is walking through the plant. Escapeways and accessibility of various areas can be easily viewed. Working in 3D, the operators gets a clearer picture of the plant which helps them to eliminate errors. They can also use an automatic clash detector to highlight any interferences.

Components are automatically placed from a specification, which means that it's virtually impossible to put a Class 150 flange in a Class 400 line. A single specification is assigned to each and every line. Once that is done, the only components that can be placed on the line are those assigned to that specification. The program also provides the ability to run consistency and connectivity checks. This usually eliminates the need to rearrange or redesign during the installation phase when changes cost perhaps 10 times more than in the early design phase. Other disciplines are also able to use the model to eliminate errors.

Chematur has just completed the first project on which 3D design was used from start to finish. It is a hydrogen peroxide plant built in Poland. This product is used in the pulp and paper and textile industries as an environmentally friendly bleaching agent. The process involves catalytic reduction of anthraquinone to the corresponding anthrahydroquinone and oxidation of this product to yield hydrogen peroxide and the original anthraquinone. The reaction mixture is extracted with water to recover hydrogen peroxide. The recovered organic phase is recycled to the hydrogenerator.

Elapsed time from the start of the design work to operation of the plant was only 25 months. Lower installation time—because there were fewer changes—and reduced engineering time were both responsible for the rapid completion of this project. Chematur's manufacturing team found it very easy to visualize piping runs depicted in the 3D format. The pipefitters agreed that the drawings were more accurate, more complete and easier to follow than those produced using the 2D format. Consequently, the manufacturing cycle was shortened while the quality and quantity of labor required to assemble the piping noticeably improved. The client was impressed with Chematur's ability to meet the delivery deadlines. Another important factor was that there was no shortage of any piping, as well as very little surplus, because of the more accurate bill of materials produced from the model database.

Because of the success of this project, every project that has been started since is also being designed in 3D. The company is currently working on three fully detailed engineering projects and several more basic engineering jobs. The company has increased the number of Omni-Series seats to ten for piping and six for equipment. All in all, switching to 3D piping engineering has dramatically improved piping engineering work at Chematur from both a cost and quality standpoint. As a result, management has stated that they never plan to do another job in 2D.

Thomas Stutterheim and Peter Olausson are managers of the Mechanical Dept. at Chematur Engineering, and Hakan Anderson is Manager of the Plant Design Dept.

For more information: Rebis, 1600 Riviera Ave. Suite 300, Walnut Creek, CA 94596. Tel: 925-933-2525. Fax: 925-933-1920.