QUALyTEK QUALIDADE, TECNOLOGIA E SISTEMAS LTDA.

TERMINOLOGIA NA MANUTENÇÃO (English) Caso não encontre um termo específico, entre em contato, para que possamos incluir no glossário. Active Maintenance Time: The time during which preventive and corrective maintenance works is actually being done on the item. Active Redundancy: The term used when all redundant units are functioning simultaneously. Active Repair Time: The time during which one or more technicians are working on the item to effect a repair. Accessibility: A design feature which affects the ease of admission to an area for the perfomance of visual and manipulative maintenance. Automatic Test Equipment (ATE): Equipment for stimulus and measurement controlled by a programmed sequence of steps (usually in software). Availability: The probability that a system or equipment when used under stated conditions and in an actual supply environment shall operate satisfactorily at any given time. Índice Burn-In: The operation of itens for a specified period of time in order to remove early failures and bring the reliability characteristic into the random failure part of the Bathtub Curve. Beach Marks: Contoured lines found on fatigue surfaces or faces of broken parts that show the progression of a crack. They resemble sand lines formed by waves washing up on a beach. They can be in a swirled or straight formation. They're useful in helping to trace the origin of fatigue. Benchmarking: Process of consistently researching for new ideas for methods, practices, and process, and of either adopting the practices or adapting the good features and implementing them to obtain the best of the best; the search for industry best practices that lead to superior performance; the continuos process of measuring one's products, services, and practices against the toughest competitors or those companies recognized as industry leaders. Benchmark Measures: A set of measurements (or metrics) used to establish goals for improvement in process, functions, products, etc. Benchmark measures are often derived from other firms that display "best of class" achievement. Brinelling: Indentations on a metallic surface. Índice Common Cause Failure: The coincident failure of two or more independent items as the result of a single cause. This is specially relevant in systems incorporating redundancy where one event causes the coincident failure of two or more normally independent channels. Confidence Interval: A range of a given variable within which a random value will lie at a stated confidence (probability). Consumer's Risk: The probability of an unacceptable batch being accepted owing to a favourable sample. Concurrent Engineering: A methodology for the design, development, and manufacture of products that meet the market/customer demand for high quality, low cost, and fast delivery; the application of Total Quality Management philosophy, tools, and techniques to the design manufacturing process in combination with the tools and techniques of computer aided design (CAD) and manufacturing (CAM). Synonym: Participative Design/Engineering Criticality: The effect of a malfunction of an item on the perfomance of a system. Corrective Maintenance is the perfomance of unplanned (unexpected) maintenance tasks to restore the functional capabilities of failed or malfunctioning equipment or systems. Crystalline: A rough surface appearance indicating sudden breakage. Crow's Foot: A line pattern found on metal surfaces, resembling bird footprints. Typically caused by the use of improper lubricants or lubricants with depleted additives. Índice Delta-Star Method: This technique is used to evaluate the reliability of complex networks such as bridges. Diagnostic Software: A program containing self-test algorithms enabling failures to be identified. Downtime: That portion of calendar time during wich the item is not in condition to perform its intended function. Derating: The use of components having a higher strength rating in order to reduce failure rate. Dependability: A measure of the item or system operating condition at one or more points during the mission. It may be stated as the probability that an item will (a) enter or occupy any one of its required operational modes during a specified mission and (b) perform the functions associated with those operational modes. Dependability is a function of operating time (reliability) and downtime (maintainability). Índice Emulation: A type of simulation whereby the simulator responds to all possible inputs as would the real item and generates all the corresponding outputs. Ergonomics: The study of man/machine interfaces in order to minimise human errors due to mental or physical fatigue. Empowerment: A condition whereby employees have the authority to make decisions and take action in their work areas without prior approval. Índice Failure: Termination of the ability of an item to perform its specified function. Fatigue: The tendency of metal or other material to crack and fail under applications of stress. Typically caused by repeated overloading of a component. Flank Cracking: Excessive surface fatigue. Similar to spalling (see below), but characterized by axial cracks. Once these cracks appear, failure can be occur rapidly. Failure Mechanism: The physical or chemical process which causes the failure. Fault Trees: This is a widely used technique in industry to evaluate the reliability of complex systems. This method was originated in the early sixties by the personnel of Bell Laboratories to evaluate the reliability and safety of the Minuteman Launch Control System. Fault Hazard Analysis Technique: This technique is used to define the effects of components failure mode. In addition, this technique is utilized to categorize the component failure modes effect on equipment. Function Analysis for Maintainability: The analytical basis for allocating tasks to personnel and equipment so as to achieve optimum system maintainability. Functional System Safety Analyses: The main objective of these analyses is to identify and determine the safety aspects associated with personnel, environment, equipment, and approaches involved during the system life cycle. Functional Test: An empirical test routine to exercise an item such that all aspects of the software are brought into use. Failure Rate: The number of failures of an item per unit time. Índice Go-no-Go Display: A display that indicates the operable or not operable condition of equipment. Galling: An advanced form of scoring in which large portions of metal tear from one surface and weld to another. Commonly caused by low lubricant levels. Índice Human Factor: The human psychological characteristics relative to complex systems, and the development and application of principles and procedures for accomplishing optimum man-machine integration and utilization. The term is used in a broad sense to cover all biomedical and psychosocial considerations pertaining to man in the system. Human Reliability: The probability of completing a task successfully by personnel within a minimum time at any required stage in system/equipment operation. Hidden Function: A function whose failure will not become evident to the operating crew under normal circumstances if it occurs on its own. Housekeeping: The manufacturing or maintenance activity of identifying and maintaining an orderly environment for preventing errors and contamination in the manufacturing process or work area. Índice Inactive Time: The period of time when a item is available, but neither needed nor operating for its intended use. Indirect Maintenance Resources: That time in manhours and material in dollars which, although not directly expended in active maintenance tasks, contributes to the over-all maintenance mission through the support of overhead operations, administration, accumulation of facility records and statistics, supervisions, and facilities upkeep. Improvement Activities: Activities that extend equipment life, reduce the time required to perform maintenance, and make maintenance unnecessary. Incremental Cost: Cost added in the process of finishing an item or assembling a group of itens. Additional cost incurred as a result of a decision. Inspection: The qualitative observation of a component's condition or perfomance. ILS - Integrated Logistic Support : A management function that provides the inicial planing, funding, and controls which help to assure that the ultimate consumer (or user) receives a system that will not only meet performance requirements, but can be supported expeditiously and economically through its programmed life cycle. A major ILS objective is to assure the integration of the various elements of support (i.e., manpower and personnel, training and training support, spare and repair parts and related inventories, test and support equipment, maintenance facilities, transportation and handling, computer resources, and technical data). ISO - International Standards Organization: A specialized international agency for standardization composed of the national bodies of 91 countries. ISO 9000 Series Standards: A set of five individual but related international standards on quality management and quality assurance developed to help companies effectively document the quality system elements to be implemented to maintain an efficient quality system. ISO 14001: International Environmental Management System (EMS) standard developed by the International Standards Organization. The standard is designed to address all facets of an organization's operations, products, and services. It covers environmental policy, resources, training, operations, emergency response, audits, measurement, and management views. It contains five major elements that an organization must satisfy to be registered or certified. These elements are policy, planning, implementation and operations, checking and corrective action, and management review. Índice Job Description: A formal statement of duties, qualifications, and responsabilities associated with a particular job. Job Walk: A formal and documented tour of the job site to familiarize bidders or contractors with field conditions. Índice "K"-out-of-"M" Unit Network: This type of redundancy is used when a certain number "k" of units in an active parallel redundant system must work for the systems sucess. Kaizen: The Japanese term for improvement. Continuing improvement involving everyone, managers and workers, in manufacturing; relates to finding and eliminating waste in machinery, labor, and production methods K-Cost: The annual maintenance cost per repairman. Índice Load Test: A system test involving simulated inputs in order to prove that the system will functions at full load. Logistic Resources: The personnel and material tools required by an item to perform its mission perfomance. It includes such things as tools, test equipment, spare part facilities, technical manuals, and administrative and supply procedures necessary to assure the availability of these resources when needed. Least Replaceable Assembly (LRA): That assembly at which diagnosis ceases and replacement is carried out. Life Cycle: All phases through wich an item, product, equipment, or systems passes from conception through disposition. Life Cycle Cost (LCC): The total cost of a piece of equipment or system over its entire lifetime; the total of all costs generated or forecasted to be generated during the design, development, production, operation, maintenance, and support process. Life Cycle Costs include direct, indirect, recurring, nonrecurring costs such as acquisition, instalation, operating, maintenance, upgrades, and removal or disposal costs. Learning Curve: A curve reflecting the rate of improvement in skills as more units of an item are made. This planning technique is particulary useful in project-oriented industries where new products are frequently phased. The basis for the learning curve calculation is that workers will be able to produce the product more quickly after they get used to making it. Synonym: experience curve. Logic Tree Analysis (LTA): A structured decision process to determine the applicability and effectiveness of preventive maintenance tasks based on the failure criticality classification, the type of equipment, the failure mode and failure cause. Logistics Support Analysis (LSA): A formal analytical technique to identify, define, analyze, qauntify, and process logistics support requirements that requires data inputs from design, reliability, system safety, and maintainability. Índice Maintenance: All actions necessary for retaining an item in, or restoring it to, a serviceable condition. Maintenance includes servicing, repair, modification, modernization, overhaul, inspection, and condition determination. Maintainability: The characteristic of design and installation wich is expressed as the probability that an item will conform to specified conditions within a given period of time when maintenance action is performed in accordance with prescribed procedures and resources. Markovian Modeling: A widely used method to predict the reliability of systems, especially when the system failure and repair rates are constant. Mean: Usually used to indicate the Arithmetic Mean which is the sum of a number of values divided by the number thereof. Median: The median is that value such that 50 per cent of the values in question are greater and 50 per cent less than it. MTTR (Mean Time To Repair): The statistical mean of the distribution of times-to-repair. The cumulation of active repair times during a given period divided by the total number of malfunction during the same time interval. MTBF (Mean Time Between Failure) and MTTF (Mean Time To Failure): The total cumulative functioning time of a population divided by the number of failures. As with failure rate the same applies to observed, assessed and extrapolated MTBF. MTBF is used for items wich involve repair. MTTF is used for items with no repair. Maintainability Index: A quantitative figure of merit which relates the maintainability of an item to a standard reference. Maintainability Parameters: A group of factors (environmental, human, hardware) which establishes limits to the performance of maintenance on a item. Maintainability Requirement: A comprehensive statement of required maintenance characteristics, expressed in qualitative and quantitative terms, to be satisfied by the design of an item. Minimal Cut Set: A cut set is a collection of basic events whose presence will cause system failure. A distinct group of cut sets consisting of a minimum number of terms are called "minimum cut sets". In other words, a cut set is minimal if it cannot be further minimized but still insures system failure. Índice Nonactive Maintenance Time: The time during which no maintenance is being accomplished on the item because of either supply or administrative reasons. Índice Operational Profile: Various equipment status phases, that is, Calendar Time, Inactive Time, Demand Usage Time, Operating Time, Downtime. Índice Parallel Network: This type of redundancy can be used to improve system reliability. The redundant system will only fail if all of its components fail. Preliminary Hazard Analysis Technique (PHA): This is a relatively an unstructured technique because of the unavailability of definitive functional flow diagrams, drawings, and so on, during the product conceptual phase. Preliminary Safety Matrix Analysis Technique (PSMA): This widely used procedure uses a matrix form to document and perform the preliminary hazard analysis. Preventive Maintenance: Is the perfomance of inspection and/or servicing tasks have been preplanned (schedule) for accomplishment at specific points in time to retain the functional capabilities of operating equipment or systems. Proficiency Test: A test which measures an individual's skill level within a given specialty. Producer's Risk: The probability of an acceptable batch being rejected owing to an unfavourable sample. Producibility: A measure of the relative ease and economy of producing a system or a product. The characteristics of design must be such that an item can be produced easily and economically, using conventional and flexible manufacturing methods and processes without sacrificing function, performance, effectiveness, or quality. Índice Qualitative Maintainability Requirement: Maintainability requirement which is expressed in qualitative terms, for example, minimize complexity, design for minimum number of tools and test equipment, and design for optimum accessibility. Quantitative Maintainability Requirement: A requirement expressed in quantitative terms, that is, a figure of merit or in measurable units of time or resources required to accomplish a specific maintenance task, or group of tasks, in relation to the applicable perfomance requirements (reaction time, availabilities, downtime, repair time, turnaround time, etc.). Índice Random: Such that each item has the same probability of being selected as any other. Ratched Marks: Small, repetitive niches found on the edges of a break. Like beach marks, they indicate metal fatigue. Reliability Growth: Increase in reliability as a result of continued design modifications resulting from field data feedback. Reliability: The probability that an item will perform a required function, under stated conditions, for a stated period of time. Since observed reliability is empirical it is defined as the ratio of itens which perform their function for the stated period to the total number in the sample. Reliability (Intrinsic / Inherent): The basic reliability level dictated by the design and components and taking no account of failures added by manufacture, installation, wearout or operation. Renewal Theory: Is utilized in the field of reliability engineering to determine, for example, how many equipment failure-repair cycles have ocurred. This knowledge is vital in order to schedule the work load of maintenance personnel and determine a proper supply of spares. Repair: The process of returning an item to a specified condition including preparation, fault location, item procurement, fault correction, adjustment and calibration, and final test. Repair Time: The time during which an item is undergoing diagnosis, repair, checkout and alignment. Redundancy: The provision of more than one means of achieving a function. Active: all items remain operating prior to failure. Standby: replicated items do not operate untill needed. Repairability: The capability of an item to be repaired. Root Beam Fatigue: Fatigue affecting gear teeth, characterized by contoured beach marks. Can start with localized craks or damage to gear roots, caused by shock loading. Rotating Bending Fatigue: Fatigue found on shafts. Occurs when a shaft is rotating under torque and subjected to a bending force. Usually evidenced by beach marks which are layered up to a crystalline area (the area of final failure). Índice Series Network: This network denotes a system whose components/subsystems are connected in a series. In a network, if any one of the system components malfunctions, it will cause system failure. Safety: This may be defined as freedom from those conditions that can cause damage to or loss of equipment or injury or death to human beings. Scoring: Etching in metal surfaces, caused when the high points of two metal surfaces scratch each other or transfer metal from one surface to another. Scoring is typically a sign of low lubricant. Shear: A fracture in a plane parallel to the applied force. Spalling: A condition characterized by an excessive state of large metal flaking. Occurs when the surface of the metal fatigues. Can appear without preliminary pitting. System Safety: The optimum level of safety subject to resource and operational effectiveness constraints attained by applying engineering and system safety management principles throughout the life cycle of a system. Simulation: The process of representing a unit by some means in order to provide some or all identical inputs, at some interface, for test purposes. Software Error: An error in the digital state of a system which may propagate to become a failure. Software Reliability: This is the probability that a software program functions without an external error for some time period on the system it is to be used under the actual working conditions. Stress: It's defined as the load wich will produce failure of a component, device, or material. The term "load" may be defined as mechanical load, environment, temperature, electric current, etc. Strenght: It's defined as the ability of a component, device, or material to accomplish its required mission satisfactorily without a failure when subject to the external loading and environment. Standby Redundant System: In this case one unit is functioning and "k"units are on a standby mission. In other words, the "k" number of units are not active. System Effectiveness: A general term covering the subject involving Reliability, Maintainability and Availability. Skill Levels: The classification system used to rate personnel as to their relative abilities to perform their assigned jobs. Índice Troubleshooting: The locating and diagnosing malfunctions or breakdows in equipment by means of systematic checking or analysis. Terotechnology: A integrated approach to the overall optimisation of life cycle costs and resources. Torsional Fatigue: Fatigue affecting shafts, commonly caused by excessive torsion applications. Unlike rotating bending fatigue, torsional fatigue has no bending force introduced with it. Typically distinguished by radial lines originating from the spline roots of the shaft in a start pattern. TPM - Total Productive Maintenance: A concept originally developed by the Japanese, constitutes an integrated, top-down, system-oriented, life-cycle approach to maintenance, with the objective of maximizing productivity. Often defined as "Productive Maintenance" implemented by all employees, is based on the principle that equipment must involve everyone in the organization, from line operators to top management. The objective is to eliminate equipment breakdowns, speed losses, minor stoppages, and so on. It promotes defect-free production, Just-In-Time (JIT) production, and automation. The concept of TPM promotes "continuous improvement in maintenance". TQM - Total Quality Management: Can be described as a totally integrated management approach that addresses system/product quality during all phases of the life cycle and at each level in the overall system hierarchy. It provides a before-the-fact orientation to quality, and it focuses on system design and development activities as well as production, manufacturing, assembly, construction, maintenance , and support, and related functions. Total Quality Management is a unification mechanism linking human capabilities to engineering, production, and support processes. TAT - Turnaround Time: That element of maintenance time needed to service, repair, and/or check out an item for recommitment. This constitutes the time that it takes an item to go through the complete cycle from its installation in the operational system, through the maintenance shop, and into the spares inventory ready for use. Índice Up Time: An element of time in which a system or equipment is either operating or in an alert or reacting state. Índice Value Engineering and/or Analysis: A disciplined approach to the elimination of waste from products or processes through an investigative process that focuses on the functions to be performed and whether such functions add value. Variable Cost: An operation cost that varies directly with a change of one unit in the production volume, for example, direct materials consumed, sales comissions. Variance: The difference between the expected value and the actual. In statistics, a measure of dispersion of data. Viscosity: The measure of the internal friction or the resistance to flow of a liquid. Volatility: The extend to which liquids vaporize. The relative tendency to vaporize. Índice Wear: The attrition or rubbing away of the surface of a material as the result of mechanical action. Wearout Stage: The final stage of failure rate with a sharp rise in the failure rate caused by exhaustion of the component's, equipment's, system's, or products durability. As components begin to fatigue or wear out, one begins to observe failures at increasing rates for a specified interval. Weibull Plot: A reliability prediction technique used to evaluate the reliability parameters of components. It is valuable during the development phase of a component. What-If Analysis: The process of evaluating alternate strategies by answering the consequences of changes to forecasts, manufacturing plans, inventory levels, etc. Índice "X" em branco Índice "Y" em branco Índice "Z" em branco Índice