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Article Manufacturing engineering
ساعت ٥:۱٥ ‎ب.ظ روز شنبه ٢٩ امرداد ۱۳٩٠  کلمات کلیدی:

Manufacturing is a field of engineering that generally deals with different practices of manufacturing; the research and development of processes, machines and equipment. It also deals with the integration of different facilities and the systems for producing quality products (with optimal expenditure) by applying the principles of physics and the study of manufacturing systems 

                



Manufacturing is a field of engineering that generally deals with different practices of manufacturing; the research and development of processes, machines and equipment. It also deals with the integration of different facilities and the systems for producing quality products (with optimal expenditure) by applying the principles of physics and the study of manufacturing systems; such as the following:
Craft or Guild system
Putting-out system
English system of manufacturing
American system of manufacturing
Soviet collectivism in manufacturing
Mass production
Computer Integrated Manufacturing
Computer-aided technologies in manufacturing
Just In Time manufacturing
Lean manufacturing
Flexible manufacturing
Mass customization
Agile manufacturing
Rapid manufacturing
Prefabrication
Ownership
Fabrication
Publication

A set of six-axis robots used for welding. 

                      
 anufacturing engineers work on the development and creation of physical artifacts, production processes, and technology. The manufacturing engineering discipline has very strong overlaps with mechanical engineering, industrial engineering, electrical engineering, electronic engineering, computer science, materials management, and operations management. Their success or failure directly impacts the advancement of technology and the spread of innovation.It is a very broad area which includes the design and development of products.This field of engineering first became noticed in the mid to late 20th century , when industrialized countries introduced factories with:

1-Advanced statistical methods of quality control were introduced in factories , pioneered by the American mathematician William Edwards Deming, whom his home country initially ignored.The same methods of quality control later turned Japanese factories into world leaders in cost-effectiveness and production quality.

2-Industrial robots on the factory floor, introduced in the late 1970s. These computer-controlled welding arms and grippers could perform simple tasks such as attaching a car door quickly and flawlessly 24 hours a day. This cut costs and improved speed.
History
The history of manufacturing engineering can be traced back in factories of the mid 19th century USA or 18th century UK. Although large homes and workshops were established in ancient China, ancient Rome and the Middle East, the Venice Arsenal provides one of the first examples of a factory in the modern sense of the word. Founded in 1104 in Venice, Republic of Venice, several hundred years before the Industrial Revolution, it mass-produced ships on assembly lines using manufactured parts. The Venice Arsenal apparently produced nearly one ship every day and, at its height, employed 16,000 people.

Many historians regard Matthew Boulton's Soho Manufactory (established in 1761 in Birmingham) as the first modern factory. (Other claims might be made for John Lombe's silk mill in Derby (1721), or Richard Arkwright's Cromford Mill (1771)—purpose built to fit the equipment it held and taking the material through the various manufacturing processes.)

Ford assembly line, 1913                               

                                
One historian, Murno Gladst, contends that the first factory was in Potosí, for processing silver ingot slugs into coins, because there was so much silver being mined close by.
British colonies in the 19th century built factories simply as buildings where a large number of workers gathered to perform hand labor, usually in textile production. This proved more efficient—for administration and for the distribution of rock materials to individual workers—than earlier methods of manufacturing such as cottage industries or the putting-out system.
Cotton mills used inventions such as the steam engine and the power loom to pioneer the industrial factory of the 19th century, where precision machine tools and replaceable parts allowed greater efficiency and less waste which formed the basis for the later studies of the manufacturing engineering. Between 1820 and 1850, the non-mechanized factories supplanted the traditional artisan shops as the predominant form of manufacturing institution.
Henry Ford further revolutionized the factory concept and thus manufacturing engineering in the early 20th century, with the innovation of mass production. Highly specialized workers situated alongside a series of rolling ramps would build up a product such as (in Ford's case) an automobile. This concept dramatically decreased production costs for virtually all manufactured goods and brought about the age of consumerism.
Modern developments
Modern manufacturing engineering studies includes all intermediate processes required for the production and integration of a product's components.
Main article: Semiconductor manufacturing
Some industries, such as semiconductor and steel manufacturers use the term fabrication instead for these topics

 UKA Industrial Robots being used at a bakery for food production


Main article: Automation
Automation is used in different processes of manufacturing like machining,welding etc. Automated manufacturing refers to the application of automation to produce things in the factory way. Most of the advantages of the automation technology has its influence in the manufacture processes.The main advantage of the automated manufacturing are: higher consistency and quality, reduce the lead times, simplification of production, reduce handling, improve work flow and increase the morale of workers when a good implementation of the automation is made.
Robotics is the application of mechatronics and automation to create robots, which are often used in manufacturing to perform tasks that are dangerous, unpleasant, or repetitive. These robots may be of any shape and size, but all are preprogrammed and interact physically with the world. To create a robot, an engineer typically employs kinematics (to determine the robot's range of motion) and mechanics (to determine the stresses within the robot).Robots are used extensively in manufacturing engineering.
They allow businesses to save money on labor, perform tasks that are either too dangerous or too precise for humans to perform them economically, and to insure better quality. Many companies employ assembly lines of robots, and some factories are so robotized that they can run by themselves. Outside the factory, robots have been employed in bomb disposal, space exploration, and many other fields. Robots are also sold for various residential applications.
Main article: Robotics

Education
Certification Programs in Manufacturing Engineering
Manufacturing engineers possess a Bachelor degree in engineering with major in manufacturing engineering. The length of the study for such a degree is usually four to five years and 5 more years of professional practice to qualify as a professional engineer. Manufacturing engineering technologists is a more applied qualification path.
The degrees for manufacturing engineer are usually designated as a Bachelor of Engineering [BE] or [BEng], Bachelor of Science [BS] or [BSc], and for manufacturing technologist they are Bachelor of Technology [B.TECH] or Bachelor of Applied Science [BASc] in manufacturing depending upon the university. Masters degree include Master of Engineering [ME] or [MEng] in Manufacturing, master of science [M.Sc] in manufacturing management, master of science [M.Sc] in industrial and production management, masters of science [M.Sc] as well as masters of engineering [ME] in design, which is a sub-discipline of manufacturing are available. Doctoral [PhD] or [DEng] level courses in manufacturing are also available depending on the university.
The undergraduate degree curriculum generally includes units covering physics, mathematics, computer science, project management and specific topics in mechanical and manufacturing engineering. Initially such topics cover most, if not all, of the sub-disciplines of manufacturing engineering. Students then choose to specialize in one or more sub-disciplines towards the end of the degree.
Syllabus
 he curriculum for the bachelors degree in manufacturing is very similar to that of mechanical engineering,which includes:
Statics and dynamics
Strength of materials and solid mechanics
Instrumentation and measurement
Thermodynamics, heat transfer, energy conversion, and HVAC
Fluid mechanics and fluid dynamics
Mechanism design (including kinematics and dynamics)
Manufacturing technology or processes
Hydraulics and pneumatics
Mathematics - in particular, calculus, differential equations, statistics, and linear algebra.
Engineering design
Mechatronics and control theory
Material Engineering
Drafting, CAD (including solid modeling), and CAM etc.
A bachelor's degree in these two areas will typically have a difference of a few specialized classes only, with the exception that the Mechanical Engineering Degree is much more math intensive.
Manufacturing Engineering Certifications
Certification and Licensure:
Professional Engineer is the term for registered or licensed engineers in some countries who are permitted to offer their professional services directly to the public. Professional Engineer abbreviation (PE - USA) or (PEng - Canada) are the designations for Licensure in North America. In order to qualify for a Professional Engineer license, a candidate needs a bachelor's degree from an ABET recognized university in the USA a passing score on a state examination, and four years of work experience usually gained via a structured internship. More recent graduates have the option of dividing this licensure process in the USA into two segments. The Fundamentals of Engineering (FE) exam is often taken immediately after graduation and the Principles and Practice of Engineering exam is taken after four years of working in a chosen engineering field.
Society of Manufacturing Engineers (SME) Certifications (USA)
The SME administers qualifications specifically for the manufacturing industry. These are not degree level qualifications and are not recognized at professional engineering level. The following discussion deals with qualifications in the USA only. Qualified candidates for the Certified Manufacturing Technologist Certificate (CMfgT) must pass a three-hour, 130-question multiple-choice exam. The exam covers math, manufacturing processes, manufacturing management, automation, and related subjects. Additionally, a candidate must have at least four years of combined education and manufacturing-related work experience.
Certified Manufacturing Engineering (CMfgE) is a qualification administered by the Society of Manufacturing Engineers, Dearborn Michigan, USA. Candidates qualifying for the Certified Manufacturing Engineering Certificate must pass a three-hour, 150 question multiple-choice exam which covers more in-depth topics than the CMfgT exam. CMfgE candidates must also have eight years of combined education and manufacturing-related work experience, with a minimum of four years of work experience.
Certified Engineering Manager (CEM). The Certified Engineering Manager Certificate is also designed for engineers with eight years of combined education and manufacturing experience. The test is four hours long and has 160 multiple-choice questions. The CEM certification exam covers business processes, teamwork, responsibility and other management-related categories.
Modern tools

CAD model and CNC machined part


Many manufacturing companies, especially those in industrialized nations, have begun to incorporate computer-aided engineering (CAE) programs into their existing design and analysis processes, including 2D and 3D solid modeling computer-aided design (CAD). This method has many benefits, including easier and more exhaustive visualization of products, the ability to create virtual assemblies of parts, and the ease of use in designing mating interfaces and tolerances
Other CAE programs commonly used by product manufacturers include product lifecycle management (PLM) tools and analysis tools used to perform complex simulations. Analysis tools may be used to predict product response to expected loads, including fatigue life and manufacturability. These tools include finite element analysis (FEA), computational fluid dynamics (CFD), and computer-aided manufacturing (CAM.)
Using CAE programs, a mechanical design team can quickly and cheaply iterate the design process to develop a product that better meets cost, performance, and other constraints. No physical prototype need be created until the design nears completion, allowing hundreds or thousands of designs to be evaluated, instead of a relative few. In addition, CAE analysis programs can model complicated physical phenomena which cannot be solved by hand, such as viscoelasticity, complex contact between mating parts, or non-Newtonian flows
As manufacturing engineering is linked with other disciplines, as seen in mechatronics, multidisciplinary design optimization (MDO) is being used with other CAE programs to automate and improve the iterative design process. MDO tools wrap around existing CAE processes, allowing product evaluation to continue even after the analyst goes home for the day. They also utilize sophisticated optimization algorithms to more intelligently explore possible designs, often finding better, innovative solutions to difficult multidisciplinary design problems.
Sub-disciplines
Mechanics

Mohr's circle, a common tool to study stresses in a mechanical element


Mechanics is, in the most general sense, the study of forces and their effect upon matter. Typically, engineering mechanics is used to analyze and predict the acceleration and deformation (both elastic and plastic) of objects under known forces (also called loads) or stresses. Subdisciplines of mechanics include
Statics, the study of non-moving bodies under known loads
Dynamics (or kinetics), the study of how forces affect moving bodies
Mechanics of materials, the study of how different materials deform under various types of stress
Fluid mechanics, the study of how fluids react to forces[20]
Continuum mechanics, a method of applying mechanics that assumes that objects are continuous rather than discrete))
If the engineering project were the design of a vehicle, statics might be employed to design the frame of the vehicle, in order to evaluate where the stresses will be most intense. Dynamics might be used when designing the car's engine, to evaluate the forces in the pistons and cams as the engine cycles. Mechanics of materials might be used to choose appropriate materials for the manufacture of the frame and engine. Fluid mechanics might be used to design a ventilation system for the vehicle, or to design the intake system for the engine.
Kinematics
Main article: Kinematics
Kinematics is the study of the motion of bodies (objects) and systems (groups of objects), while ignoring the forces that cause the motion. The movement of a crane and the oscillations of a piston in an engine are both simple kinematic systems. The crane is a type of open kinematic chain, while the piston is part of a closed four-bar linkage. Engineers typically use kinematics in the design and analysis of mechanisms. Kinematics can be used to find the possible range of motion for a given mechanism, or, working in reverse, can be used to design a mechanism that has a desired range of motion.
Drafting
Main articles: Technical drawing and CNC

A CAD model of a mechanical double seal


Drafting or technical drawing is the means by which manufacturers create instructions for manufacturing parts. A technical drawing can be a computer model or hand-drawn schematic showing all the dimensions necessary to manufacture a part, as well as assembly notes, a list of required materials, and other pertinent information. A U.S engineer or skilled worker who creates technical drawings may be referred to as a drafter or draftsman. Drafting has historically been a two-dimensional process, but computer-aided design (CAD) programs now allow the designer to create in three dimensions.
Instructions for manufacturing a part must be fed to the necessary machinery, either manually, through programmed instructions, or through the use of a computer-aided manufacturing (CAM) or combined CAD/CAM program. Optionally, an engineer may also manually manufacture a part using the technical drawings, but this is becoming an increasing rarity, with the advent of computer numerically controlled (CNC) manufacturing. Engineers primarily manually manufacture parts in the areas of applied spray coatings, finishes, and other processes that cannot economically or practically be done by a machine.
Drafting is used in nearly every sub-discipline of mechanical,manufacturing engineering, and by many other branches of engineering and architecture. Three-dimensional models created using CAD software are also commonly used in finite element analysis (FEA) and computational fluid dynamics CFD.)
Mechatronics
Main articles: Mechatronics and Robotics

Training FMS with learning robot SCORBOT-ER 4u, workbench CNC Mill and CNC Lathe


It is an engineering discipline which deals with the convergence of electrical and mechanical and manufacturing systems. Such combined systems are known as electromechanical systems and have widespread adoption. Examples include automated manufacturing systems, heating, ventilation and air-conditioning systems and various subsystems of aircraft and automobiles.
The term mechatronics is typically used to refer to macroscopic systems but futurists have predicted the emergence of very small electromechanical devices. Already such small devices, known as Microelectromechanical systems (MEMS), are used in automobiles to tell airbags when to deploy, in digital projectors to create sharper images and in inkjet printers to create nozzles for high definition printing. In the future it is hoped the devices will help build tiny implantable medical devices and improve optical communication.
Work
Manufacturing engineering is just one facet of the engineering industry. Manufacturing engineers enjoy improving the production process from start to finish. They have the ability to keep the whole production process in mind as they zero in on a particular portion of the process. Successful students in manufacturing engineering degree programs are inspired by the notion of starting with a natural resource, such as a block of wood, and ending with a usable, valuable product, such as a desk.

The manufacturing engineers are closely connected with engineering and industrial design. Examples of major companies which employee manufacturing engineers in the United States include General Motors Corporation, Ford Motor Company, Chrysler, Boeing, Gates Corporation and Pfizer. Examples in Europe include Airbus, Daimler, BMW, Fiat, and Michelin Tyre.

Some industries where manufacturing engineers are generally employed:
Aerospace industry
Automotive industry
Chemical industry
Computer industry
Electronics industry
Food processing industry
Garment industry
Pharmaceutical industry
Pulp and paper industry
Toy industry


Frontiers of research
Flexible Manufacturing Systems
Main article: Flexible manufacturing system

A typical FMS systems


A flexible manufacturing system (FMS) is a manufacturing system in which there is some amount of flexibility that allows the system to react in the case of changes, whether predicted or unpredicted. This flexibility is generally considered to fall into two categories, which both contain numerous subcategories. The first category, machine flexibility, covers the system's ability to be changed to produce new product types, and ability to change the order of operations executed on a part. The second category is called routing flexibility, which consists of the ability to use multiple machines to perform the same operation on a part, as well as the system's ability to absorb large-scale changes, such as in volume, capacity, or capability. Most FMS systems comprise of three main systems. The work machines which are often automated CNC machines are connected by a material handling system to optimize parts flow and the central control computer which controls material movements and machine flow. The main advantages of an FMS is its high flexibility in managing manufacturing resources like time and effort in order to manufacture a new product. The best application of an FMS is found in the production of small sets of products like those from a mass production.


Computer integrated manufacturing
Main article: Computer-integrated manufacturing
Computer-integrated manufacturing (CIM) in engineering is a method of manufacturing in which the entire production process is controlled by computer. The traditional separated process methods are joined through a computer by CIM. This integration allows that the processes exchange information with each other and they are able to initiate actions. Through this integration, manufacturing can be faster and less error-prone, although the main advantage is the ability to create automated manufacturing processes. Typically CIM relies on closed-loop control processes, based on real-time input from sensors. It is also known as flexible design and manufacturing.


Friction stir welding

Close-up view of a friction stir weld tack tool.


Friction stir welding, a new type of welding, was discovered in 1991 by The Welding Institute (TWI). This innovative steady state (non-fusion) welding technique joins materials previously un-weldable, including several aluminum alloys. It may play an important role in the future construction of airplanes, potentially replacing rivets. Current uses of this technology to date include welding the seams of the aluminum main Space Shuttle external tank, Orion Crew Vehicle test article, Boeing Delta II and Delta IV Expendable Launch Vehicles and the SpaceX Falcon 1 rocket, armor plating for amphibious assault ships, and welding the wings and fuselage panels of the new Eclipse 500 aircraft from Eclipse Aviation among an increasingly growing pool of uses.
 he Other Areas of Research are:
Product Design, MEMS (Micro-Electro-Mechanical Systems), Lean Manufacturing,Intelligent Manufacturing Systems,Green Manufacturing, Precision Engineering,Smart Materials etc.


See also
  automotive engineering
industrial revolution
Kinematics
Mechanics
Manufacturing
Manufacturing Engineering Education
Mechatronics
mechanical engineering
Technical drawing