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Design & Manufacturing - Short Answer Questions from AMIE Exams

Explain the following.

Welding
Welding: Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing fusion, which is distinct from lower temperature metal-joining techniques such as brazing and soldering, which do not melt the base metal, hi addition to melting the base metal, a filler material is often added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that can be as strong, or even stronger, than the base material. Pressure may also be used in conjunction with heat, or by itself, to produce a weld.

CNC
Computer Numeric Control (CNC) is the automation of machine tools that are operated by precisely programmed commands encoded on a storage medium as opposed to controlled manually by hand wheels or lever's or mechanically automated by cams alone. Most NC today is computer (or computerized) numerical control (CNC). in which computers play an integral part of the control.

Heat treatment
Heat Treatment is the controlled heating and cooling of metals to alter then physical and mechanical properties without changing the product shape. Heat treatment is sometimes done inadvertently due to manufacturing processes that either heat or cool the metal such as welding or forming.

Information technology
Information technology (IT) is the application of computers to store, retrieve, transmit and manipulate data, often in the context of a business or other enterprise.)

Drilling operation 
Drilling is a cutting process that uses a drill bit to cut a hole of circular cross-section in solid materials. The drill bit is usually a rotary cutting tool, often multipoint. The bit is pressed against the workpiece and rotated at rates from hundreds to thousands of revolutions per minute.

Extrusion
Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through a die of the desired cross-section. 
The two main advantages of this process over other manufacturing processes are its ability to create very complex cross-sections, and to work materials that are brittle, because the material only encounters compressive and shear stresses. It also forms pails with an excellent surface finish.

Robust design
Robust product design is a concept from the teachings of Dr Taguchi, a Japanese quality gum. It is defined as reducing variation in a product without eliminating the causes of the variation, hi other words, making the product or process insensitive to variation. Examples of robust design include umbrella fabric that will not deteriorate when exposed to varying environments (external variation), food products that have long shelf lives (internal variation), and replacement parts that will fit properly (unit to unit variation).

Product design specifications
Product design specification (PDS) is a statement of how a design is made (specify the design), what it is intended to do. and how far it complies with the requirements. Requirements may be gathered in the Product Requirement Specification (PRS). Its aim is to ensure that the subsequent design and development of a product meets the needs (or requirements) of the user.

Brainstorming
Brainstorming is the name given to a situation when a group of people meet to generate new ideas around a specific area of interest. Using rules which remove inhibitions, people are able to think more freely and move into new areas of thought and so create numerous new ideas and solutions. The participants shout out ideas as they occur to them and then build on the ideas raised by others. All the ideas are noted down and are not criticized. Only when the brainstorming session is over are the ideas evaluated.

Grinding processes
Grinding is an abrasive machining process that uses a grinding wheel as the cutting tool. Grinding is used to finish workpieces that must show high surface quality (e.g., low surface roughness) and high accuracy of shape and dimension. Surface grinding and cylindrical a few grinding processes.

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The study material for AMIE/B Tech/Junior Engineer exams is available at https://amiestudycircle.com.

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