Ch. 1 Manufacturing Introduction : Manufacturing



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Analysis


  • Accept Situation: Here, the designers decide on committing to the project and finding a solution to the problem. They pool their resources into figuring out how to solve the task most efficiently.

  • Analyze:" In this stage, everyone in the team begins research. They gather general and specific materials which will help to figure out how their problem might be solved. This can range from statistics, questionnaires, and articles, among many other sources.



Concept


  • Define: This is where the key issue of the matter is defined. The conditions of the problem become objectives, and restraints on the situation become the parameters within which the new design must be constructed.



Synthesis


  • Ideate: The designers here brainstorm different ideas, solutions for their design problem. The ideal brainstorming session does not involve any bias or judgment, but instead builds on original ideas.

  • Select: By now, the designers have narrowed down their ideas to a select few, which can be guaranteed successes and from there they can outline their plan to make the product.

  • Implement: This is where the prototypes are built, the plan outlined in the previous step is realized and the product starts to become an actual object.

  • Evaluate: In the last stage, the product is tested, and from there, improvements are made. Although this is the last stage, it does not mean that the process is over. The finished prototype may not work as well as hoped so new ideas need to be brainstormed

Product design considerations:-

  • The manufacturer is concerned with production cost; in the end, the manufacturer wants an economically produced product.

  • The purchaser looks at price, appearance, and prestige value.

  • The end user is concerned with usability and functionality of the final product.

  • The maintenance and repair department focuses on how well the final product can be maintained: is the product easily reassembled, disassembled, diagnosed, and serviced?

Manufacturing technology in Egypt :-

During the 20th century, manufacturing grew to be one of the largest sectors of Egypt’s economy, accounting (along with mining) for roughly one-fourth of the GDP by the 21st century. Domestic manufactures were weak from the late 19th century until about 1930 because of free trade policies that favoured importing foreign products. Motivated by the need to increase national income, to diversify the economy, and to satisfy the aspirations of nascent nationalism, the government imposed a customs tariff on foreign goods in 1930 that promoted the development of Egyptian manufactures.

problems of industry in Egypt:-

The economy is at risk. A short sentence which ultimately describes the unprecedented decline of economic conditions in Egypt

- Poverty rates currently stand at 70%;

- Economic growth has dropped to between 1% and 2%;

- Hard currency reserves have declined from $36 billion to $28 billion

- The flow of foreign investments is down to zero;

- Budget deficit has reached EGP1290 billion;

- The general debt is calculated at EGP1080 billion, i.e. 90% of GDP;

- The proceeds from tourism are down by 40%.

- The Stock Exchange has lost EGP20 billion.



solutions of problem of industry in Egypt:-

- To create an atmosphere suitable for attracting investments and tourists.

- To create the economic conditions likely to ensure the re-launch of the money market. 
- To develop the banking system and to institutionalize investment transparency.
- To fight corruption and consolidate democracy.
- To protect the country’s financial and monetary sectors

Ch.2

programming software

CAD:-

Computer-aided design (CAD) is the use of computer systems to assist in the creation, modification, analysis, or optimization of a design.[1] CAD software is used to increase the productivity of the designer, improve the quality of design, improve communications through documentation, and to create a database for manufacturing.[2] CAD output is often in the form of electronic files for print, machining, or other manufacturing operations.

Computer-aided design is one of the many tools used by engineers and designers and is used in many ways depending on the profession of the user


CAD



CAM

CNC

CAE

FEA

We will talk about some of this types



CAM:-

Computer-aided manufacturing (CAM) is the use of computer software to control machine tools and related machinery in the manufacturing of work pieces. This is not the only definition for CAM, but it is the most common;[1] CAM may also refer to the use of a computer to assist in all operations of a manufacturing plant, including planning, management, transportation and storage



Machining Process in CAM:-

Most machining progresses through many stages,[9] each of which is implemented by a variety of basic and sophisticated strategies, depending on the material and the software available. The stages are:



Roughing

This process begins with raw stock, known as billet, and cuts it very roughly to shape of the final model. In milling, the result often gives the appearance of terraces, because the strategy has taken advantage of the ability to cut the model horizontally. Common strategies are zig-zag clearing, offset clearing, plunge roughing, rest-roughing.



Semi-finishing

This process begins with a roughed part that unevenly approximates the model and cuts to within a fixed offset distance from the model. The semi-finishing pass must leave a small amount of material so the tool can cut accurately while finishing, but not so little that the tool and material deflect instead of shearing. Common strategies are raster passes, waterline passes, constant step-over passes, pencil milling.



Finishing

Finishing involves a slow pass across the material in very fine steps to produce the finished part. In finishing, the step between one pass and another is minimal. Feed rates are low and spindle speeds are raised to produce an accurate surface.



Contour milling

In milling applications on hardware with five or more axes, a separate finishing process called contouring can be performed. Instead of stepping down in fine-grained increments to approximate a surface, the workpiece is rotated to make the cutting surfaces of the tool tangent to the ideal part features. This produces an excellent surface finish with high dimensional accuracy.



CNC:-

Numerical control (NC) is the automation of machine tools that are operated by abstractly programmed commands encoded on a storage medium, as opposed to controlled manually via hand wheels or levers, or mechanically automated via cams alone. The first NC machines were built in the 1940s and 1950s, based on existing tools that were modified with motors that moved the controls to follow points fed into the system on punched tape. These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern computer numerical control (CNC) machine tools that have revolutionized the machining processes.





In modern CNC systems, end-to-end component design is highly automated using computer-aided design (CAD) and computer-aided manufacturing (CAM) programs. The programs produce a computer file that is interpreted to extract the commands needed to operate a particular machine via a postprocessor, and then loaded into the CNC machines for production. Since any particular component might require the use of a number of different tools—drills, saws, etc., modern machines often combine multiple tools into a single "cell". In other cases, a number of different machines are used with an external controller and human or robotic operators that move the component from machine to machine. In either case, the complex series of steps needed to produce any part is highly automated and produces a part that closely matches the original CAD design.

G-Codes (Preparatory Functions)

Code Function

G00 Rapid positioning

G01 Linear interpolation

G02 Circular interpolation clockwise (CW)

G03 Circular interpolation counterclockwise (CCW)

G20 Inch input (in.)

G21 Metric input (mm)

G24 Radius programming

G28 Return to reference point

G29 Return from reference point

G32 Thread cutting

G40 Cutter compensation cancel

G41 Cutter compensation left

G42 Cutter compensation right

G43 Tool length compensation positive (+) direction

G44 Tool length compensation minus (-) direction

G49 Tool length compensation cancels

G 53 Zero offset or M/c reference

G54 Settable zero offset

G84 canned turn cycle

G90 Absolute programming

G91 Incremental programming

M-Codes (Miscellaneous Functions)

M or miscellaneous codes are used to either turn ON or OFF different functions,

which control certain machine tool operations. M-codes are not grouped into

categories, although several codes may control the same type of operations such as

M03, M04, and M05, which control the machine tool spindle. Some of important

codes are given as under with their function s:

Code Function

M00 Program stop

M02 End of program

M03 Spindle start (forward CW)

M04 Spindle start (reverse CCW)

M05 Spindle stop

M06 Tool change

M08 Coolant on

M09 Coolant off36

M10 Chuck - clamping

M11 Chuck - unclamping

M12 Tailstock spindle out

M13 Tailstock spindle in

M17 Tool post rotation normal

M18 Tool post rotation reverse

M30 End of tape and rewind or main program end

M98 Transfer to subprogram

M99 End of subprogram



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