Project
A project in business and science is a collaborative enterprise, frequently involving research or design, that is carefully planned to achieve a particular aim. In term of Engineering projects are, in which requires that such projects should be carried out by registered engineers and/or registered engineering companies. That is, companies with license to carry out such works as design and construction of buildings, power plants, industrial facilities, installation and erection of electrical gri networks, transportation infrastructure and the like. Initially, the project scope is defined and the appropriate methods for completing the project are determined. Following this step, the durations for the various tasks necessary to complete the work are listed and grouped into a work breakdown structure. The logical dependencies between tasks are defined using an activity network diagram that enables identification of the critical path. Float or slack time in the schedule can be calculated using project management software. Then the necessary resources can be estimated and costs for each activity can be allocated to each resource, giving the total project cost. At this stage, the project plan may be optimized to achieve the appropriate balance between resource usage and project duration to comply with the project objectives. Once established and agreed, the plan becomes what is known as the baseline. Progress will be measured against the baseline throughout the life of the project. Analyzing progress compared to the baseline is known as earned value management.
The scope of the project is specified in a contract between the owner and the engineering and construction parties. As a rule, an engineering project is broken down into design and construction phases. The outputs of the design process are drawings, calculations, and all other design documentation necessary to carry out the next phase.
Flow Line Production
Manufacturing systems can be individual work cells, consisting of a single production machine and an operator. In other cases they are linked as groups of machines and workers, for example, a production line. The manufacturing systems come in direct physical contact with the parts and/or assemblies being made so they "touch" the product.
Flow line production involves multiple workstations arranged in sequence, and the parts or assemblies are physically moved through the sequence to complete the product. Flow production involves a continuous movement of items through the production process. This means that when one task is finished the next task must start immediately. Therefore, the time taken on each task must be the same. The workstations consist of production machines and/or workers equipped with specialized tools. The layout is called a product layout, and the workstations are arranged into one long line.
Flow line production is suitable for mass production which is the high quantity range (10,000 to millions of units per year). Flow production (often known as mass production) involves the use of production lines such as in a car manufacturer where doors, engines, bonnets and wheels are added to a chassis as it moves along the assembly line. It is appropriate when firms are looking to produce a high volume of similar items. Two categories of mass production can be distinguished:
(1) Quantity production and
(2) Flow line production.
Quantity production involves the mass production of single parts on single pieces of equipment. Although flow line production can produce million products per year, but the product variety is low. This is due to the high production cost if we produce high variety product for a flow line production. The setup for the equipment and machinery will be very costly. So, product variety is inversely proportional to the production quantity. When the product variety is high, production quantity is low and vice versa.
The advantage of flow line production is capital intensive. This means it uses a high proportion of machinery in relation to workers, as is the case on an assembly line. The advantage of this is that a high number of products can roll off assembly lines at very low cost. This is because production can continue at night and over weekends and also firms can benefit from economies of scale, which should lower the cost per unit of production.
In contrast, the disadvantage of flow line production is that with so much machinery it is very difficult to alter the production process. This makes production inflexible and means that all products have to be very similar or standardized and cannot be modified to individual tastes. However some “variety” can be achieved by applying different finishes, decorations at the end of the production line.
Cellular Manufacturing
The cellular manufacturing system, often called lean manufacturing, is a fairly recent development in global manufacturing processes. One of the first, and today, the most common cellular, or lean manufacturing systems is the Kaizen system. Originally conceived by the Toyota Corporation in Japan, Kaizen utilizes technology and cellular manufacturing to reduce the waste of time, effort, money, and resources in the production process.
The main objective of lean manufacturing is the minimization of waste, called muda, to achieve maximum efficiency of resources. It means that having the flexibility to produce a high variety of low demand products, while maintaining the high productivity of large scale production. Cellular manufacturing, sometimes called cellular or cell production, arranges factory floor labor into semi-autonomous and multi-skilled teams, or work cells, who manufacture complete products or complex components.
In order to set up a single process flow (or single product flow) line, it is necessary to locate all the different equipment needed to manufacture the product together in the same production area. This is in contrast with the traditional 'batch and queue' set-up wherein only similar equipment are put in the same area. Under a 'batch and queue' set-up, products that need to undergo processing under certain equipment need to be transported to the area where the equipment is located.
The single process flow set-up described above is an example of a 'work cell'. A work cell is defined as a collection of equipment and workstations arranged in a single area that allows a product or group of similar products to be processed completely from start to finish. It is, in essence, a self-contained mini-production line that caters to a group of products that undergo the same production process. Cellular manufacturing involves the use of work 'cells', which is how it got its name.
Because of the free flow of materials in cellular manufacturing, it has the ability to produce products just in time. This means that every unit processed at one station will get processed in the next station. As such, no inventories that have already undergone processing at one station will be left unprocessed in another station. This prevents the build-up of non-moving inventories, which are products that have already incurred some production costs but can’t generate revenues because they are stuck somewhere along the process.
FIGURE: Cellular Manufacturing Systems, Machine Guarding Technology and cellular manufacturing have combined to streamline the production processes of numerous established and start-up manufacturing facilities worldwide. Lean systems, such as Kaizen, and Six Sigma, to name just two, though very often high in startup cost, provide both a short- and long-term benefit in reducing the waste common to the traditional production line. The bottom line in any manufacturing enterprise is profit. Cellular manufacturing has been proven to dramatically increase profits.
Function Process
A function process or functional model in systems engineering and software engineering is a structured representation of the functions (activities, actions, processes, operations) within the modeled system or subject area.
A function model, also called an activity model or process model is a graphical representation of an enterprise's function within a defined scope. The purposes of the function model are to describe the functions and processes, assist with discovery of information needs, help identify opportunities, and establish a basis for determining product and service costs.Job Processing
Introduction
Job production, sometimes called jobbing, involves producing a one-off product for a specific customer. Job production is most often associated with small firms (making railings for a specific house, building/repairing a computer for a specific customer, making flower arrangements for a specific wedding etc.) but large firms use job production too. Examples include:
- Designing and implementing an advertising campaign
- Auditing the accounts of a large public limited company
- Building a new factory
- Installing machinery in a factory
- Machining a batch of parts per a CAD drawing supplied by a customer
Fabrication shops and machine shops whose work is primarily of the job production type are often called job shops. The associated people or corporations are sometimes called jobbers
Benefits and disadvantages
Key benefits of job production include:
- work is generally of a high quality
- a high level of customization is possible to meet the customer's exact requirements
- significant flexibility is possible, especially when compared to mass production
- workers can be easily motivated due to the skilled nature of the work they are performing
Disadvantages include:
- higher cost of production
- requires the use of specialist labour (compare with the repetitive, low-skilled jobs in mass production)
- slow compared to other methods (batch production and mass production)
Concurrent Engineering
Several definitions of concurrent engineering are in use.
The first one is used by the Concurrent Design Facility (ESA):
| Concurrent Engineering (CE) is a systematic approach to integrated product development that emphasizes the response to customer expectations. It embodies team values of co-operation, trust and sharing in such a manner that decision making is by consensus, involving all perspectives in parallel, from the beginning of the product life cycle. |
The second one is by Pennell and Winner, 1989:
| Concurrent Engineering is a systematic approach to the integrated, concurrent design of products and their related processes, including, manufacturing and support. This approach is intended to cause the developers from the very outset to consider all elements of the product life cycle, from conception to disposal, including cost, schedule, quality and user requirements. |
Definition
Concurrent engineering, also known as simultaneous engineering, is a non-linear product or project design approach during which all phases of manufacturing operate at the same time - simultaneously. Both product and process design run in parallel and occur in the same time frame. Product and process are closely coordinated to achieve optimal matching of requirements for effective cost, quality, and delivery. Decision making involves full team participation and involvement. The team often consists of product design engineers, manufacturing engineers, marketing personnel, purchasing, finance, and suppliers.
Concurrent engineering techniques can be used to compress time in the product development cycle, and business cycles in general. Every business has basic cycles that govern the way that paper is processed, parts are manufactured, and decisions are made. They may be documented in the form of procedures or routings. Examples of business cycles are customer order, product development, production, and procurement.
The concurrent engineering method is still a relatively new design management system, but has had the opportunity to mature in recent years to become a well-defined systems approach towards optimizing engineering design cycles. Because of this, concurrent engineering has gathered much attention from industry and has been implemented in a multitude of companies, organizations and universities, most notably in the aerospace industry.
Concurrent engineering is an excellent tool to use in improving productivity and inducing velocity within an operation. It can reduce the time-to-market, engineering times in general, overall throughput time, and costs. It can be applied to a variety of circumstances where operations are performed in sequence and contribute to excessive lead times.
The basic premise for concurrent engineering revolves around two concepts. The first is the idea that all elements of a product’s life-cycle, from functionality, producibility, assembly, testability, maintenance issues, environmental impact and finally disposal and recycling, should be taken into careful consideration in the early design phases.
The second concept is that the preceding design activities should all be occurring at the same time, or concurrently. The overall goal being that the concurrent nature of these processes significantly increases productivity and product quality, aspects that are obviously important in today's fast-paced market. This philosophy is key to the success of concurrent engineering because it allows for errors and redesigns to be discovered early in the design process when the project is still in a more abstract and possibly digital realm. By locating and fixing these issues early, the design team can avoid what often become costly errors as the project moves to more complicated computational models and eventually into the physical realm.
One of the most important reasons for the huge success of concurrent engineering is that by definition it redefines the basic design process structure that was common place for decades. This was a structure based on a sequential design flow, sometimes called the ‘Waterfall Model’.Concurrent engineering significantly modifies this outdated method and instead opts to use what has been termed an iterative or integrated development method. The difference between these two methods is that the ‘Waterfall’ method moves in a completely linear fashion by starting with user requirements and sequentially moving forward to design, implementation and additional steps until you have a finished product. The problem here is that the design system does not look backwards or forwards from the step it is on to fix possible problems. In the case that something does go wrong, the design usually must be scrapped or heavily altered. On the other hand, the iterative design process is more cyclic in that, as mentioned before, all aspects of the life cycle of the product are taken into account, allowing for a more evolutionary approach to design.
A significant part of this new method is that the individual engineer is given much more say in the overall design process due to the collaborative nature of concurrent engineering. Giving the designer ownership plays a large role in the productivity of the employee and quality of the product that is being produced. This stems from the fact that people given a sense of gratification and ownership over their work tend to work harder and design a more robust product, as opposed to an employee that is assigned a task with little say in the general process.
Batch
Batch-The quantity of material required for or produced by one operation. An amount of material subjected to some unit chemical process or physical mixing process to make the final product substantially uniform.
Batch production is the manufacturing technique of creating a group of components at a workstation before moving the group to the next step in production. Batch production is common in bakeries and in the manufacture of sports shoes, pharmaceutical ingredients (APIs), inks, paints and adhesives. In the manufacture of inks and paints, a technique called a colour-run is used. A colour-run is where one manufactures the lightest colour first, such as light yellow followed by the next increasingly darker colour such as orange, then red and so on until reaching black and then starts over again. This minimizes the cleanup and reconfiguring of the machinery between each batch. White (by which is meant opaque paint, not transparent ink) is the only colour that cannot be used in a colour-run because a small amount of white pigment can adversely affect the medium colours. The chemical, tire, and process industry (CPT) segment uses a combination of batch and process manufacturing depending the product and plant.
Batch production is the manufacturing technique of creating a group of components at a workstation before moving the group to the next step in production. Batch production is common in bakeries and in the manufacture of sports shoes, pharmaceutical ingredients (APIs), inks, paints and adhesives. In the manufacture of inks and paints, a technique called a colour-run is used. A colour-run is where one manufactures the lightest colour first, such as light yellow followed by the next increasingly darker colour such as orange, then red and so on until reaching black and then starts over again. This minimizes the cleanup and reconfiguring of the machinery between each batch. White (by which is meant opaque paint, not transparent ink) is the only colour that cannot be used in a colour-run because a small amount of white pigment can adversely affect the medium colours. The chemical, tire, and process industry (CPT) segment uses a combination of batch and process manufacturing depending the product and plant.
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