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Design For Inspection
Design for Inspection (DFI) is an engineering principle that proposes that inspection methods and measurement instruments used to certify manufacturing conformity, should be considered early in the design of products. Production processes should be designed in such a way that features of the product are easy to inspect with readily available measurement instruments, and so that measurement uncertainty is considered in the tolerance that are applied. The concept can be applied in almost all engineering disciplines. DFI describes the process of designing or engineering a product in order to facilitate the measurement in order to reduce the overall costs of manufacturing and delivering products that satisfy customers. The role of inspection in the manufacturing process is to ensure that the manufacturing process is producing components that meet the specification requirements. Inspection does not assure the quality of the product, only a robust and repeatable manufacturing process c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measurement Instruments
A measuring instrument is a device to measure a physical quantity. In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item under study and the referenced unit of measurement. Measuring instruments, and formal test methods which define the instrument's use, are the means by which these relations of numbers are obtained. All measuring instruments are subject to varying degrees of instrument error and measurement uncertainty. These instruments may range from simple objects such as rulers and stopwatches to electron microscopes and particle accelerators. Virtual instrumentation is widely used in the development of modern measuring instruments. Time In the past, a common time measuring instrument was the sundial. Today, the usual measuring inst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measurement Uncertainty
In metrology, measurement uncertainty is the expression of the statistical dispersion of the values attributed to a measured quantity. All measurements are subject to uncertainty and a measurement result is complete only when it is accompanied by a statement of the associated uncertainty, such as the standard deviation. By international agreement, this uncertainty has a probabilistic basis and reflects incomplete knowledge of the quantity value. It is a non-negative parameter. The measurement uncertainty is often taken as the standard deviation of a state-of-knowledge probability distribution over the possible values that could be attributed to a measured quantity. Relative uncertainty is the measurement uncertainty relative to the magnitude of a particular single choice for the value for the measured quantity, when this choice is nonzero. This particular single choice is usually called the measured value, which may be optimal in some well-defined sense (e.g., a mean, median, or m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inspection
An inspection is, most generally, an organized examination or formal evaluation exercise. In engineering activities inspection involves the measurements, tests, and gauges applied to certain characteristics in regard to an object or activity. The results are usually compared to specified requirements and standards for determining whether the item or activity is in line with these targets, often with a Standard Inspection Procedure in place to ensure consistent checking. Inspections are usually non-destructive. Inspections may be a visual inspection or involve sensing technologies such as ultrasonic testing, accomplished with a direct physical presence or remotely such as a remote visual inspection, and manually or automatically such as an automated optical inspection. Non-contact optical measurement and photogrammetry have become common NDT methods for inspection of manufactured components and design optimisation. A 2007 Scottish Government review of scrutiny of public ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Design For Manufacture
Design for manufacturability (also sometimes known as design for manufacturing or DFM) is the general engineering practice of designing products in such a way that they are easy to manufacture. The concept exists in almost all engineering disciplines, but the implementation differs widely depending on the manufacturing technology. DFM describes the process of designing or engineering a product in order to facilitate the manufacturing process in order to reduce its manufacturing costs. DFM will allow potential problems to be fixed in the design phase which is the least expensive place to address them. Other factors may affect the manufacturability such as the type of raw material, the form of the raw material, dimensional tolerances, and secondary processing such as finishing. Depending on various types of manufacturing processes there are set guidelines for DFM practices. These DFM guidelines help to precisely define various tolerances, rules and common manufacturing checks relate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Design For Assembly
Design for assembly (DFA) is a process by which product design, products are designed with ease of Manufacturing, assembly in mind. If a product contains fewer parts it will take less time to assemble, thereby reducing assembly costs. In addition, if the parts are provided with features which make it easier to grasp, move, orient and insert them, this will also reduce assembly time and assembly costs. The reduction of the number of parts in an assembly has the added benefit of generally reducing the total cost of parts in the assembly. This is usually where the major cost benefits of the application of design for assembly occur. Approaches Design for assembly can take different forms. In the 1960s and 1970s various rules and recommendations were proposed in order to help designers consider assembly problems during the design process. Many of these rules and recommendations were presented together with practical examples showing how assembly difficulty could be improved. Howeve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metrology
Metrology is the scientific study of measurement. It establishes a common understanding of units, crucial in linking human activities. Modern metrology has its roots in the French Revolution's political motivation to standardise units in France when a length standard taken from a natural source was proposed. This led to the creation of the decimal-based metric system in 1795, establishing a set of standards for other types of measurements. Several other countries adopted the metric system between 1795 and 1875; to ensure conformity between the countries, the Bureau International des Poids et Mesures (BIPM) was established by the Metre Convention. This has evolved into the International System of Units (SI) as a result of a resolution at the 11th General Conference on Weights and Measures (CGPM) in 1960. Metrology is divided into three basic overlapping activities: * The definition of units of measurement * The realisation of these units of measurement in practice * Traceabi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cost Of Quality
In process improvement efforts, quality costs or cost of quality is a means to quantify the total cost of quality-related efforts and deficiencies. It was first described by Armand V. Feigenbaum in a 1956 Harvard Business Review article. Prior to its introduction, the general perception was that higher quality requires higher costs, either by buying better materials or machines or by hiring more labor. Furthermore, while cost accounting had evolved to categorize financial transactions into revenues, expenses, and changes in shareholder equity, it had not attempted to categorize costs relevant to quality, which is especially important given that most people involved in manufacturing never set hands on the product. By classifying quality-related entries from a company's general ledger, management and quality practitioners can evaluate investments in quality based on cost improvement and profit enhancement. Definitions Feigenbaum defined the following quality cost areas: The cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Design For Manufacturability
Design for manufacturability (also sometimes known as design for manufacturing or DFM) is the general engineering practice of designing products in such a way that they are easy to manufacture. The concept exists in almost all engineering disciplines, but the implementation differs widely depending on the manufacturing technology. DFM describes the process of designing or engineering a product in order to facilitate the manufacturing process in order to reduce its manufacturing costs. DFM will allow potential problems to be fixed in the design phase which is the least expensive place to address them. Other factors may affect the manufacturability such as the type of raw material, the form of the raw material, dimensional tolerances, and secondary processing such as finishing. Depending on various types of manufacturing processes there are set guidelines for DFM practices. These DFM guidelines help to precisely define various tolerances, rules and common manufacturing checks relate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Design For X
Design for Excellence or Design For Excellence (DfX or DFX), are terms and expansions used interchangeably in the existing literature, where the ''X'' in ''design for X'' is a variable which can have one of many possible values. In many fields (e.g., very-large-scale integration (VLSI) and nanoelectronics) ''X'' may represent several traits or features including: manufacturability, power, variability, cost, yield, or reliability.Saraju Mohanty, Chapter 3 Nanoelectronics Issues in Design for excellence,Nanoelectronic Mixed-Signal System Design, and 0071825711, 1st Edition, McGraw-Hill, 2015. This gives rise to the terms design for manufacturability (DfM, DFM), design for inspection (DFI), design for variability (DfV), design for cost (DfC). Similarly, other disciplines may associate other traits, attributes, or objectives for ''X''. Under the label ''design for X'', a wide set of specific design guidelines are summarized. Each design guideline addresses a given issue that is cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
