4 Engineering Drawing Assignment Questions & Answers To Elevate Your Knowledge
- Time crunch
- Inadequate knowledge
- Lack of resources needed to complete the assignment
- Fear of failing
What are the stages in the development of a new product?
Discuss the importance of having standard parts design and manufacturing
- simplifies the design, as standard parts are usually already designed and manufactured.
- makes production more economical, as standard parts are mass- produced, hence relatively cheaper, and are usually kept in stock.
- reduces the cost of maintenance of a product already in use, due to the interchangeability of standard parts.
Why is a drawing office essential and why does it differ from firm to firm?
- to prepare the design layouts and assembly and production drawings necessary for the manufacture of products.
- to make decisions on materials to be used, methods of manufacture, heat treatment, etc.
- to calculate the stresses for the designed components, to ensure that the components will withstand the applied forces when manufactured and in use.
- to estimate from the drawings the cost of manufacture of designed components.
- to store all drawings, technical information, and reference material.
- to provide a technical service for all departments in the firm.
- to liaise with people outside the firm.
What is the main function of a reproduction print room in engineering drawings?
The function of a reproduction or print room is to copy engineering drawings, tracings, and documents. The copies obtained are used for reference, manufacturing, assembly, and storage purposes. There are four popular reproduction methods: the dye-line (diazo) process, the microfilm the xerographic process, and computer plotting
The dye-line (diazo) process
The tracing is placed over special printing paper and is exposed to ultra-violet light, which bleaches away the sensitive coating on the printing paper, except where the ink lines on the tracing prevent light passing. The exposed paper is then developed, to show the lines of the tracing in dark colors. The print obtained is the same size as the original drawing.
The microfilm process
The original drawing or tracing is photographically reduced on to a film. The film, when developed, may be stored on a reel or may be cut and placed in cellophane envelopes or mounted in cards or frames. When the drawing is to be referred to, the film is projected on to a screen or enlarged and printed directly. The drawing or tracing must be of good standard – the lines must be drawn black and thick and well-spaced, detail reduced and lettering clear.
Xerographic process
This uses a plate coated with a material which conducts electricity when exposed to light and acts as an insulator in the dark. The plate surface is positively charged in the dark and a drawing is projected on to it. Plate areas corresponding to white areas of the drawing are exposed to light and lose their charge; dark areas, corresponding to the image of the drawing, retain their positive charge. The plate is then dusted with a negatively charged powder which adheres only to the positively charged areas. A positively charged paper is pressed against the plate, attracting the particles of powder, and finally heat is applied to fuse those particles permanently to the paper. This process is suitable only for reproducing small-sized drawings and documents.