Quality circles, or QCs, are generally defined as “small groups of volunteers from the same work area who meet regularly to identify, analyze, and solve quality and related problems in their area of responsibility” (Munchus, 1983: 255). They usually consist of eight to ten members and meet once a week during normal working hours. Moveover, members of QCs usually receive some form of training in problem-solving techniques.
(Ricky W. Griffin, The Academy of Management Journal Vol. 31, No. 2 (Jun., 1988), pp. 338)
(February 23, 2011)
Quality Circle (new) (Better)
There are various forms and styles of participative management.One of them which is widely applied and practised is ‘Quality Circles’. The ‘quality circle’ concept first originated in USA which was very succesfully applied in Japan afterwards. This technique boosted the japaneese firms to endeavour for high quality products at low costs.
But first let us look at the meaning of ‘Quality Circle’ technique. Basically it consist of a group of eight to ten employees who meet each other during a meeting which is held once in a week, fortnight or month depending upon the problems and their frequency of generation. These members discuss various problems related to quality. They recommend alternative solutions to solve the problems by investigating the causes. Depending upon the recommedations, corrections are made. Corrections are checked and accepted as a norm if the solution works. They generally hold their meeting in the organization premises. They are generally given a room where they can meet and think and come out with solution to problems. These employees basically have a shared area of responsibilities. This leads to a good participative enviroment and greater acceptibility of decisions. Since the employees are not very good at analyzing and decision making, the part of quality circle includes teaching employees group communication skills, quality strategies and measurement and problem analysis techniques.
2) AGV (Automated guided vehicles) (Automation)
Automated guided vehicles can move workpieces a great distance,
but they lack the speed found in both robot and transfer
lines. Yet because of their ability to be programmed to different
routes, they are more flexible than transfer lines.AGV
Automated guided vehicles (which are are the lastest development in material movement in plants) operate automatically along pathways which in-floor wiring (or tapes for optical scanning) without operator intervention. This transport system has high flexibility and is capable of random delivery to different workstations.
(Sabrie Soloman, Sensors and Control Systems in Manufacturing, 2nd edition, page 250)
(February 16, 2011)
AGV (new) (Better)
An automated guided vehicle system (AGVS) is a material handling system that uses independently operated, self-propelled vehicles guided along defined pathways. The vehicles
arc powered by on-board batteries that allow many hours of operation (8-16 hr is typical) between recharging. A distinguishing feature of an AGVS. compared to rail guided vehicle systems and most conveyor systems, is that the pathways are unobtrusive, An AOVS is appropriate where different materials are rnovco from various load points to various unload points. An AGVS is therefore suitable for automating material handling in batch production and mixed model production. The first AGV was operated in 1954.
(Automation,Production Systems and CIM 2001, Mikell P. Groover, p.295)
3) Computer Integrated Manufacturing (CIM): (Manufacturing Method)
Computer Integrated Manufacturing (CIM), which describes the computerized integration of all aspects of product design, process planning, production, and distribution, as well as the management and operation of the whole manufacturing organization.
(Kalpakjian S., Schmid S.R., Manufacturing engineering and technology, 5th Edition, pg. 1192)
(February 15, 2011)
Computer Integrated Manufacturing (new) (Better)
Computer Integrated Manufacturing (CIM) encompasses the entire range of product development and manufacturing activities with all the functions being carried out with the help of dedicated software packages. The data required for various functions are passed from one application software to another in a seamless manner. For example, the product data is created during design. This data has to be transferred from the modeling software to manufacturing software without any loss of data. CIM uses a common database wherever feasible and communication technologies to integrate design, manufacturing and associated business functions that combine the automated segments of a factory or a manufacturing facility. CIM reduces the human component of manufacturing and thereby relieves the process of its slow, expensive and error-prone component. CIM stands for a holistic and methodological approach to the activities of the manufacturing enterprise in order to achieve vast improvement in its performance.
This methodological approach is applied to all activities from the design of the product to customer support in an integrated way, using various methods, means and techniques in order to achieve production improvement, cost reduction, fulfillment of scheduled delivery dates, quality improvement and total flexibility in the manufacturing system. CIM requires all those associated with a company to involve totally in the process of product development and manufacture. In such a holistic approach, economic, social and human aspects have the same importance as technical aspects.
CIM also encompasses the whole lot of enabling technologies including total quality management, business process reengineering, concurrent engineering, workflow automation, enterprise resource planning and flexible manufacturing.
A distinct feature of manufacturing today is mass customization. This implies that though the products are manufactured in large quantities, products must incorporate customer-specific changes to satisfy the diverse requirements of the customers. This requires extremely high flexibility in the manufacturing system.
(CAD/CAM/CIM, P. Radhakrishnan,S. Subramanian,V. Raju, p.1)
4) Master Production Schedule (MPS): (Production Planning)
Master production schedule contains the requirements for finished goods and dates for their completion.In most companies this is usually a mixture of firm orders and sales forecasts.
(AN INTRODUCTION TO COMPUTER AIDED PRODUCTION MANAGEMENT-1st Edition-Stephen J. Childe-P.39)
(February 26, 2011)
Master Production Schedule (MPS) (new) (Better)
lt is a list or the products to be manufactured, when they should be completed and delivered, and in what quantities. The master schedule must be based on an accurate estimate of demand and a realistic assessment of the company's production capacity. Products included in the MPS divide into three categories:
(1) finn customer orders,
(2) forecasted demand, and
(3) spare parts.
Proportions in each category vary for different companies, and in some cases one or more categories are omitted. Companies producing assembled products will generally have to handle all three types. In the case of customer orders for specific products, the company is usually obligated to delivery the item by a particular date that has been promised by the sales department. In the second category. Production output quantities are based on statistical forecasting techniques applied to previous demand patterns, estimates by the sales staff. and other sources. For many companies, forecasted demand constitutes the largest portion of the master schedule. The third category consists of repair parts that will either be stocked in the company's service department or sent directly to the customer. Some companies exclude this third category from the master schedule since it does not represent end products.
(Automation,Production Systems and CIM 2001, Mikell P. Groover, p.799)
5) Transfer mechanism and transfer lines:
Transfer mechanisms are used to move the workpiece from one station to another in the machine or from one machine to another to enable various operations to be performed on the part. Workpieces are transferred by methods, including rails along which parts (which usually are placed on pallets) are pushed or pulled by various mechanisms, rotary indexing tables, and overhead conveyors.
The transfer of parts from station to station usually is controlled by sensors and other devices. Tools on transfer machines easily can be changed using tool-holders with quick-change features, and the machines can be equipped with various automatic gaging and inspection systems. These systems are utilized between operations to ensure that the dimensions of a part produced in one station are within acceptable tolerances before that part is transferred to the next station. Transfer machines also are used extensively in automated assembly.
The transfer lines or flow lines in a very large system for producing cylinder heads for engine blocks consisting of a number of transfer machines. This system is capable of producing 100 cylinder heads per hour. Note the various machining operations performed: milling, drilling, reaming, boring, tapping, honing, washing and gaging.
(Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, 5th Edition, p. 1151)
(February 20, 2011)
Transfer mechanism and transfer lines (new) (Better)
The manufacturing systems considered in this chapter are used for high production of parts
that require multiple processing operations. Each processing operation is performed at a
workstation, and the stations are physically integrated by means of a mechanized work
transport system to form an automated production line. Machining (milling, drilling, and
similar rota ling cutter operations) is a common process performed on these production
Jines, in which case the term transfer line or transfer machine is used. In our classification
of manufacturing systems (Section ]3.2), transfer lines are type III A, case S (fixed routing
or parts, automated, single model systems). Other applications of automated production
lines include robotic spotwelding in automobile final assembly plants, sheet metal
pressworking, and electroplating of metals. Similar automated lines are used for assembly
operations; however, the technology of automated assembly is sufficiently different that we
postpone coverage of this topic until the next chapter.
Automated production lines require a significant capital investment. They are examples
of fixed automation, and it is generally difficult to alter the sequence
and content of the processing operations once the line is built. Their application is therefore
appropriate only under the following conditions:
• High product demand, requiring high production quantities.
• Stable product design. Frequent design changes are difficult to cope with on an automated
production line.
• Long product life, at least several years in most cases.
• Multiple operations are performed on the product during its manufacture.
When the application satisfies these conditions.automated production lines provide the following
benefits:
• Low direct labor content
• Low product cost because cost of fixed equipment is spread over many units.
• High production rates.
• Production lead time (the time between beginning of production and completion of
a finished unit) and work-in-process are minimized.
• Factory floor space is minimized.
In this chapter. we examine the technology of automated production lines and develop
several mathematical models that can be used to analyze their operation.
(Automation, Production Systems and CIM 2001, Mikell P. Groover ,p.564-565)
