Manufacturing engineering is the field of engineering that designs and optimizes the manufacturing process, or the steps through which raw materials are transformed into a final product. The manufacturing process begins with the product design, and materials specification. These materials are then modified through manufacturing to become the desired product.
manufacturing
Modern manufacturing includes all intermediate processes involved in the production and integration of a product's components. Some industries, such as semiconductor and steel manufacturers, use the term fabrication instead.
Copper smelting is believed to have originated when the technology of pottery kilns allowed sufficiently high temperatures.[12] The concentration of various elements such as arsenic increase with depth in copper ore deposits and smelting of these ores yields arsenical bronze, which can be sufficiently work hardened to be suitable for manufacturing tools.[12] Bronze is an alloy of copper with tin; the latter being found in relatively few deposits globally caused a long time to elapse before true tin bronze became widespread. During the Bronze Age, bronze was a major improvement over stone as a material for making tools, both because of its mechanical properties like strength and ductility and because it could be cast in molds to make intricately shaped objects. Bronze significantly advanced shipbuilding technology with better tools and bronze nails, which replaced the old method of attaching boards of the hull with cord woven through drilled holes.[13] The Iron Age is conventionally defined by the widespread manufacturing of weapons and tools using iron and steel rather than bronze.[14] Iron smelting is more difficult than tin and copper smelting because smelted iron requires hot-working and can be melted only in specially designed furnaces. The place and time for the discovery of iron smelting is not known, partly because of the difficulty of distinguishing metal extracted from nickel-containing ores from hot-worked meteoritic iron.[15]
During the growth of the ancient civilizations, many ancient technologies resulted from advances in manufacturing. Several of the six classic simple machines were invented in Mesopotamia.[16] Mesopotamians have been credited with the invention of the wheel. The wheel and axle mechanism first appeared with the potter's wheel, invented in Mesopotamia (modern Iraq) during the 5th millennium BC.[17] Egyptian paper made from papyrus, as well as pottery, were mass-produced and exported throughout the Mediterranean basin. Early construction techniques used by the Ancient Egyptians made use of bricks composed mainly of clay, sand, silt, and other minerals.[18]
Electrification of factories, which had begun gradually in the 1890s after the introduction of the practical DC motor and the AC motor, was fastest between 1900 and 1930. This was aided by the establishment of electric utilities with central stations and the lowering of electricity prices from 1914 to 1917.[33] Electric motors allowed more flexibility in manufacturing and required less maintenance than line shafts and belts. Many factories witnessed a 30% increase in output owing to the increasing shift to electric motors. Electrification enabled modern mass production, and the biggest impact of early mass production was in the manufacturing of everyday items, such as at the Ball Brothers Glass Manufacturing Company, which electrified its mason jar plant in Muncie, Indiana, U.S. around 1900. The new automated process used glass blowing machines to replace 210 craftsman glass blowers and helpers. A small electric truck was now used to handle 150 dozen bottles at a time whereas previously used hand trucks could only carry 6 dozen bottles at a time. Electric mixers replaced men with shovels handling sand and other ingredients that were fed into the glass furnace. An electric overhead crane replaced 36 day laborers for moving heavy loads across the factory.[34]
Lean manufacturing (also known as just-in-time manufacturing), was developed in Japan in the 1930s. It is a production method aimed primarily at reducing times within the production system as well as response times from suppliers and to customers.[37][38] It was introduced in Australia in the 1950s by the British Motor Corporation (Australia) at its Victoria Park plant in Sydney, from where the idea later migrated to Toyota.[39] News spread to western countries from Japan in 1977 in two English-language articles: one referred to the methodology as the "Ohno system", after Taiichi Ohno, who was instrumental in its development within Toyota.[40] The other article, by Toyota authors in an international journal, provided additional details.[41] Finally, those and other publicity were translated into implementations, beginning in 1980 and then quickly multiplying throughout the industry in the United States and other countries.[42]
Emerging technologies have offered new growth methods in advanced manufacturing employment opportunities, for example in the Manufacturing Belt in the United States. Manufacturing provides important material support for national infrastructure and also for national defense.
On the other hand, most manufacturing processes may involve significant social and environmental costs. The clean-up costs of hazardous waste, for example, may outweigh the benefits of a product that creates it. Hazardous materials may expose workers to health risks. These costs are now well known and there is effort to address them by improving efficiency, reducing waste, using industrial symbiosis, and eliminating harmful chemicals.
The negative costs of manufacturing can also be addressed legally. Developed countries regulate manufacturing activity with labor laws and environmental laws. Across the globe, manufacturers can be subject to regulations and pollution taxes to offset the environmental costs of manufacturing activities. Labor unions and craft guilds have played a historic role in the negotiation of worker rights and wages. Environment laws and labor protections that are available in developed nations may not be available in the third world. Tort law and product liability impose additional costs on manufacturing. These are significant dynamics in the ongoing process, occurring over the last few decades, of manufacture-based industries relocating operations to "developing-world" economies where the costs of production are significantly lower than in "developed-world" economies.
From a financial perspective, the goal of the manufacturing industry is mainly to achieve cost benefits per unit produced, which in turn leads to cost reductions in product prices for the market towards end customers.[43] This relative cost reduction towards the market, is how manufacturing firms secure their profit margins.[44]
In addition to general overviews, researchers have examined the features and factors affecting particular key aspects of manufacturing development. They have compared production and investment in a range of Western and non-Western countries and presented case studies of growth and performance in important individual industries and market-economic sectors.[47][48]
According to the United Nations Industrial Development Organization (UNIDO), China is the top manufacturer worldwide by 2019 output, producing 28.7% of the total global manufacturing output, followed by United States, Japan, Germany and India.[52][53]
UNIDO also publishes a Competitive Industrial Performance (CIP) Index, which measures the competitive manufacturing ability of different nations. The CIP Index combines a nation's gross manufacturing output with other factors like high-tech capability and the nation's impact on the world economy. Germany topped the 2020 CIP Index, followed by China, South Korea, the United States and Japan. [54][55]
Establishments in the Manufacturing sector are often described as plants, factories, or mills and characteristically use power-driven machines and materials-handling equipment. However, establishments that transform materials or substances into new products by hand or in the worker's home and those engaged in selling to the general public products made on the same premises from which they are sold, such as bakeries, candy stores, and custom tailors, may also be included in this sector. Manufacturing establishments may process materials or may contract with other establishments to process their materials for them. Both types of establishments are included in manufacturing.
This section provides information relating to employment and unemployment in manufacturing. While most data are obtained from employer or establishment surveys, information on industry unemployment comes from a national survey of households. The following tables present an overview of the industry including the number of jobs, the unemployment rate of those previously employed in the industry, job openings and labor turnover, union membership and representation, gross job gains and losses, data for occupations common to the industry, and projections of occupational employment change.
This section presents data on employee earnings and weekly hours. The latest industry averages of hourly earnings and weekly hours, as well as weekly earnings by union membership status, are shown. In addition, recent hourly and annual earnings are shown for occupations commonly found in manufacturing. This section also contains information on the average cost of benefits paid by employers, as well as recent rates of change in wages and total compensation.
This section presents data for the industry on the number of workplace fatalities and the rates of workplace injuries and illnesses per 100 full-time workers in manufacturing. An injury or illness is considered to be work-related if an event or exposure in the work environment either caused or contributed to the resulting condition or significantly aggravated a pre-existing condition.
This section presents data on the number of establishments and the number of establishments experiencing job gains or job losses in manufacturing. Also included in this section is information on productivity and costs, presented as indexes and changes in output per hour and unit labor costs. 2ff7e9595c
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