Technical Drawings and their Types...

Technical Drawings and their Types Technical drawings are also known as ‘engineering drawings’. They are means of communications and convey technical information of plant and equipment. They describe three-dimensional objects through the medium of two-dimensional paper. The process of producing technical drawings, and the skill of producing those, is often referred to as ‘drafting’. Technical drawing is normally accepted as legal document and is frequently being used for regulatory approvals. Technical drawings are most frequently used to establish engineering requirements. They describe typical applications and minimum content requirements. They are standardized tools of graphical language which avoid verbal exchanges. They are used and understood by the technical personnel speaking different languages and belonging to different countries and cultures. Technical drawings are prepared in such a way that they convey complete information of the plant and equipment clearly and concisely. They often contain more than just a graphic representation of the subject. They also contain dimensions, notes and specifications. Clarity is the essential aspect of the technical drawings. They normally represent two dimension view of the object though some drawings also provide three dimensional views. They are prepared either manually or with the aid of computer. They are generally prepared or printed in standard size of paper. Except a few category of drawings (e.g. process flow diagrams, control diagrams, piping and instruments diagrams, and single line diagrams etc.), all the drawings are normally prepared in plan and different section views usually to the scale in order to provide complete information of the drawing object. Often help of standardized symbols are taken in the drawing for depicting certain equipments or instruments. Those informations which cannot be given in the plan and sections view such as material specification, tolerances, and bill of materials etc. are normally given in a...

Phases in the Design and Construction of a Steel Plant Jul10

Phases in the Design and Construction of a Steel Plant...

Phases in the Design and Construction of a Steel Plant  Steel plant is a project which is highly capital intensive and need a very long time for its construction and commissioning. Further steel plant is to operate for a very large number of years after commissioning and during this period steel plant has to cope with the changes in the operating environment. Hence proper decision making is of utmost importance during the different phases of the plant till commissioning.  Any faulty decision during the implementation phase can create a lot of problems for the operating personnel and they have to live with the problem throughout the life of the plant. Various phases of the design of a steel plant and the decisions needed during these phases are described here. Selection of product mix Steel plant is set up to produce certain primary steel products which are required by the customers. During the production of primary steel products, some secondary products and by products are also produced which are to be sold. Selection of the product mix is a very important decision making process since the technology and production process selection in the plant depends on the product mix. Criteria for selection of the product mix include market survey, future demand projections by dependable agencies, and government policies and projections etc. Another important criterion for the selection of the product mix is the type of market the plant is to serve after commissioning. The market can be (i) captive use, (ii) local market, (iii) national market, (iv) export market, or (v) all of them. Site selection and land acquisition After the product mix is frozen the next step is the selection of site for the steel plant. The selection of a suitable site is a...