PRODUCT DESIGN
Product Design can be defined as the idea generation, concept development, testing and manufacturing or implementation of a physical object or service. It covers more than the discipline name - Industrial Design. Product Designers conceptualize and evaluate ideas, making them tangible through products in a more systematic approach.
As with most of the design fields the idea for the design of a product arises from a need and has a use. It follows certain method and can sometimes be attributed to more complex factors such as:
Factors influencing product design:
1. Design for function.
2. Design for salability
3. Changing market6 requirements
4. Adding new features
5. Increasing product’s life
6. Gaining competitiveness
Typical Phases of Product Development
1. Planning : This is referred to as phase 0 since it precedes project approval and the ;launch of actual product development process.
2. Concept Development: The needs of the target are identified, alternative product concepts are generated and evaluated.
3. System-Level design: It includes the definition of the product architecture and the decomposition of the product into sub-systems and components. The final assembly scheme is defined during this period.
4. Design Detail: it includes the complete specification of the geometry, materials and tolerances of all the unique parts in the product top be purchased from the suppliers.
5. Testing and Refinement: This phase involves the construction and evaluation of multiple preproduction versions of the product.
6. Production Ramp-up: In this phase the product is made using the intended production system. The purpose here is to train the work-force and to work out any remaining problems in the production processes.
PROCESS SELECTION:
Process selection refers to the strategic decision of selecting which kind of production process too have in the manufacturing plant. This process selection is probably wider than the plant layout problem. It affects cost, quality, delivery, and flexibility.
Factors influencing the process selection:
1. Customer order
2. Market conditions
3. Capital requirements
4. Labor availability
5. Managerial skills
6. Raw material
7. Technology available
Types of processes:
Project: deals with one-of-a-kind products that are tailored to the unique requirements of each customer. A construction company , with its many kinds and sizes of projects , is an example[le of this. Since, the products cannot be standard, the conversion process must be flexible in its equipment capabilities, human skills and procedures.
Job Shop: it is a process appropriate for manufactures of small batches of different products, each of which is custom designed and hence requires its own unique set of processing steps. Printing press illustrates job shop technology. Each product uses only a small portion of the shop’s human resources and general purpose equipment. Much time is spent waiting for access to equipment; some equipment is overloaded while the other equipment is idle, depending upon the mix of jobs at hand.
Batch technology: is a step ahead from job shop in product standardization but is not as standardized as the assembly line process. In this kind, each time a fixed lot / size/ batch of a particular product is produced before switching to next variety. Like job shop it also produces, a wide variety of products in a wide variety of volumes. The system must be flexible for the low volume / high variety products.
Assembly Line: This technology facilitates a narrow range of standardized products. For example, laundry appliances. Since the product designs are relatively stable , specialized equipment , human skills , and management systems can be developed and dedicated to the limited range of products and volumes. Beyond this range the system is rigid.
Continuous flow technology/ Flow Shop: This is exemplified by chemical plants and oil refineries. Materials and products are produced in continuous, endless flows, rather than in batches of discrete units. The product is highly standardized. This technology affords high volume, around the clock operation, with capital intensive and specialized automation.
VALUE ANALYSIS/VALUE ENGINEERING
The objective of the Value Analysis is to achieve equivalent or better performance at a lower cost while maintaining all functional requirements defined by the customer. It is done by illuminating the unnecessary costs. Value Engineering uses intuitive logic (a unique "how" - "why" questioning technique) and the analysis of Function to identify relationships that increase Value.
Does the item have any design features that are not necessary?
Can two or more parts be combined into one?
How can we cut down the weight?
Are there nonstandard parts that can be eliminated?
FACILITY LOCATION
Facility location, also known as location analysis, is a branch of operations research concerning itself with mathematical modeling and solution of problems concerning the placement of facilities in order to minimize transportation costs, avoid placing hazardous materials near housing, outperform competitors' facilities, etc.
Competitive Imperatives Impacting Location:
- The need to produce close to the customer due to time-based competition, trade agreements, and shipping costs
- The need to locate near the appropriate labor pool to take advantage of low wage costs and/or high technical skills
Issues in Facility Location:
Proximity to Customers
Business Climate
Total Costs
Infrastructure
Quality of Labor
Suppliers
Other Facilities
Free Trade Zones
Political Risk
Government Barriers
Trading Blocs
Environmental Regulation
Host Community
Competitive Advantage
Steps in location selection:
Define the location objectives and associated constraints
Identify the relevant decision criteria
Relate the objectives to the criteria using appropriate methods
Do field research to relevant data and use the models to evaluate the alternative locations
Select the location that best satisfy the criteria
FACILITY LAYOUT Defined
Facility layout can be defined as the process by which the placement of departments, workgroups within departments, workstations, machines, and stock-holding points within a facility are determined
This process requires the following inputs:
Specification of objectives of the system in terms of output and flexibility
Estimation of product or service demand on the system
Processing requirements in terms of number of operations and amount of flow between departments and work centers
Space requirements for the elements in the layout
Space availability within the facility itself
Basic Production Layout Formats
Process Layout (also called job-shop or functional layout)
Product Layout (also called flow-shop layout)
Group Technology (Cellular) Layout
Fixed-Position Layout
1.) Process Layout: CRAFT Approach
- Computerized Relative Allocation Facilities Technique (CRAFT) is a heuristic program; it uses a simple rule of thumb in making evaluations: "Compare two departments at a time and exchange them if it reduces the total cost of the layout."
- It does not guarantee an optimal solution
- CRAFT assumes the existence of variable path material handling equipment such as forklift trucks.
2.) Product Layout:
The basic difference between product layout and process layout is the pattern of work flow. Adopting a product layout makes sense when the batch size of a given product or part is large relative to the number of different products or parts produced.
Assembly Lines:
Assembly Lines are a special case of product layout. In general, the term refers to progressive assembly linked by some material handling device.
The usual assumption is that some form of pacing is present and allowable processing time is equivalent, for all workstations. [Cycle Time]
There are various types of lines, e.g., roller conveyor, overhead crane, U-shaped line, etc.
Line Balancing is a study which comprises the selection of appropriate combination of work tasks to be performed at each workstation so that the work is performed in a feasible sequence.
The line balancing mainly ensures that each workstation gets equal amount of time approximately.
The most common assembly line is a moving conveyor that passes a series of workstations in a uniform time interval called the workstation cycle time
At each workstation work is performed on a product either by adding parts or by completing assembly operations.
3.) Group Technology (Cellular) Layout:
Group Technology (Cellular) Layout allocates dissimilar machines into cells to work on products that have similar shapes and processing requirements. This layout is widely used in metal fabricating, computer chip manufacture, and assembly work. The overall objective is to gain the benefits of product layout in job-shop kinds of production. These benefits include:
Better Human Relations: Cells consist of a few workers who form a small work team ; a team turns out complete units of work.
Improved Operator Expertise: workers see only a limited no. of different parts in a finite production cycle, so repetition means quick learning.
Less in-process inventory and material handling: A cell combines several production stages, so fewer parts travel through the shop.
Faster Production Setup: Fewer jobs mean reduced tooling and hence faster tooling changes.
4.) Fixed Position Layout:
Fixed – Position Layout is characterized by a relatively low no. of production units in comparison with process and product layout formats. In developing a fixed position layout, visualize the product as the hub of a wheel with materials and equipments arranged concentrically around the production point in their order of use and movement difficulty.
In this layout, a high degree of task ordering is common. This procedure would be expected in making a layout for a large machine tool, such as stamping machine, where manufacture follows a rigid sequence.
JOB DESIGN DEFINED
Job design is the function of specifying the work activities of an individual or group in an organizational setting
The objective of job design is to develop jobs that meet the requirements of the organization and its technology and that satisfy the jobholder’s personal and individual requirements.
make this as a Fig.
Job Design Decisions
Who: Mental and physical characteristics of the work force.
What: Tasks to be performed
Where: Geographic locale of the organization; location of work areas
When: Time of day; time of occurrence in the work flow
Why: Organizational rationale for the job; objectives and motivation of the worker
How: Method of performance and motivation
All this explanation make ‘Ultimate Job Structure’
Trends in Job Design
Quality control as part of the worker's job
Cross-training workers to perform multi skilled jobs
Employee involvement and team approaches to designing and organizing work
"Informating" ordinary workers through e-mail and the Internet
Extensive use of temporary workers
Automation of heavy manual work
Creating alternative workplaces
Organizational commitment to providing meaningful and rewarding jobs for all employees
Behavioral Considerations in Job Design
Specialization of labor: This is the two edged sword of job design. On one hand specialization has made possible high speed , low cost production, and from a materialistic standpoint, it has greatly enhanced our standards of living. On the other hand , extreme specialization often have serious adverse effects on workers, which in turn are passed on to the management. In essence, the problem is to decide how much specialization is enough?
To improve the quality of jobs , leading organizations try different approaches to job design. Two popular contemporary approaches are : Job Enrichment and Sociotechnical Systems.
Job Enrichment: It involves adjusting a specialized job to make it more interesting to the job holder. A job is said to be enlarged horizontally , if the worker performs a greater no. of variety of tasks, and it is said to be enlarged vertically, if the worker is involved in planning, organizing, and inspecting his or her own work. Today, the common practice is to apply both horizontal and vertical enlargement to a given job and refer to the total approach as Job Enrichment.
Sociotechnical systems: Consistent with job enrichment philosophy but focusing more on the interaction between technology and the work group. This approach attempts to develop jobs that adjust the needs of the production process technology to the needs of the worker and work group.
Physical Considerations in Job Design
- Work physiology sets work-rest cycles according to the energy expended in various parts of the job. The harder the work, the more the need for rest periods.
- Ergonomics is a term used to describe the study of the physical arrangement of the work space together with tools used to perform a task. Fit the work to the body rather than forcing the body to conform to the work.
WORK MEASUREMENT Defined
Work measurement is a process of analyzing jobs for the purpose of setting time standards. In it we determine how much time an avg. worker takes to complete a job under std. working conditions.
Work standard can be set only for the jobs which satisfy the following conditions:
- The work should be measurable with definite start and finish time.
- It should have clearly defined steps.
- The output of the work to be studied should be large enough to justify the expenditure incurred on the work measurement.
Why use it?
- Schedule work and allocate capacity
- Motivate and measure work performance
- Evaluate performance
- Provide benchmarks
Advantages:
- Helps in reducing the efforts involved in a job by minimizing unnecessary movements.
- Helps in identifying inefficient methods and replacing them with efficient ones.
- Helps in improving machine utilization by reducing idle time.
- Provides benchmarks for evaluating worker’s performance, thus, helps managers in determining appropriate compensation.
Techniques Of Work Measurement:
There are 4 basic techniques of work measurement , which consist of 2 direct and 2 indirect methods. The direct methods are Time Study , which uses a stopwatch to time the work , and Work Sampling, which entails recording random observations of a person or teams at work. The two indirect methods are , Predetermined Motion-Time Data Systems (PMTS) , which sum data from tables of generic movement times developed in the laboratory to arrive at a time for the job (the most widely used are proprietary systems – Methods Time Measurements [MTM] and Most Work Measurement System [MOST] ), and Elemental Data, which sums times from a database of similar combinations of movements to arrive at job time. The choice of technique depends on the level of the detail desired and the nature of the work itself.
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