Drawing equipment and materials form the foundation of accurate and professional engineering drawings in chemical engineering practice. In Kenya, chemical engineers rely on precise drawings to communicate design intent, process layouts, and safety details for plants and equipment. This chapter introduces the essential tools and materials, emphasizing proper use and maintenance to ensure quality output and sustainability in line with environmental regulations.

1.1 Drawing equipment

Drawing equipment consists of various instruments that enable chemical engineers to produce clear, precise, and standardized drawings. These tools facilitate the creation of parallel lines, angular measurements, and scaled representations vital for design communication.

1.1.1 Drawing boards

• Drawing boards must have a smooth and durable surface to avoid damaging drawing papers.
• They are usually made from wood or plastic with a non-reflective finish to reduce glare.
• The size should accommodate standard drawing sheets used in chemical engineering design.
• Boards often include clips or clamps to hold papers firmly during drawing.
• Proper storage on racks prevents warping or damage to the board surface.

1.1.2 T Square

• The T square head must fit snugly against the drawing board edge to maintain alignment.
• Used primarily for drawing horizontal lines and as a guide for set squares.
• It can be made of wood, plastic, or metal for durability and smooth movement.
• T squares require regular cleaning to avoid ink or graphite buildup.
• Storage should prevent bending or warping to maintain accuracy.

1.1.3 A pair of set squares

• Set squares are used with the T square to draw vertical and angled lines.
• Made from transparent plastic to allow visibility of underlying drawing details.
• The edges should be straight and free from chips to ensure precision.
• They assist in creating accurate projections and isometric views in chemical plant layouts.
• Proper cleaning and storage prevent scratches and maintain transparency.

1.1.4 Drawing set

• Compasses enable precise circles and arcs essential in pipe layout and vessel design.
• Dividers are used to transfer measurements and divide lines proportionally.
• Protractors measure and draw exact angles, important in valve and flange positioning.
• French curves help draw smooth, non-circular curves such as piping bends.
• Regular calibration and cleaning maintain the accuracy of these instruments.

1.1.5 Use and maintenance of drawing equipment

• Always clean drawing instruments after use to remove graphite, ink, or dust residues.
• Store equipment in designated cases or drawers to avoid damage and loss.
• Inspect edges of rulers and set squares regularly for chips or warping.
• Lubricate moving parts of compasses and dividers to ensure smooth operation.
• Replace worn pencils and erasers to maintain line clarity and precision.

1.1.6 Environmental regulations on waste disposal

Relevant legislations in Kenya

• The Environmental Management and Coordination Act (EMCA) governs waste management practices.
• The Waste Management Regulations require proper disposal of hazardous and non-hazardous waste.
• The National Environment Management Authority (NEMA) oversees enforcement of environmental laws.
• Drawing materials such as used papers and masking tapes must be disposed of responsibly.
• Chemical engineers must ensure that waste from drawing offices does not contaminate the environment.

Compliance and best practices

• Segregate recyclable paper waste from non-recyclable materials.
• Use designated bins for paper scraps and used masking tapes.
• Avoid burning drawing waste to prevent air pollution.
• Partner with licensed waste management firms for waste collection and recycling.
• Train staff on environmental awareness related to drawing material disposal.

Chapter Summary

This chapter covers the essential drawing equipment required for engineering drawing, including drawing boards, T squares, and pairs of set squares, as well as comprehensive drawing sets. It also discusses the various drawing materials such as drawing papers, pencils, erasers, masking tapes, and paper clips, highlighting their appropriate uses. The chapter emphasizes the importance of proper use and maintenance of both drawing equipment and materials to ensure accuracy and longevity. Additionally, it addresses environmental considerations by referencing relevant legislation on the disposal of waste generated during drawing activities. Understanding these tools and materials, along with responsible handling and disposal, forms the foundation for producing high-quality technical drawings. Proper care and adherence to environmental regulations contribute to sustainable engineering practices.