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AS 1290.8-1995 Linear measuring instruments used in construction Levelling staves 被代替 发布日期 :  1995-12-05 实施日期 : 

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定价: 156元 / 折扣价: 133 加购物车

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定价: 156元 / 折扣价: 133 加购物车

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定价: 156元 / 折扣价: 133 加购物车

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定价: 156元 / 折扣价: 133 加购物车

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定价: 156元 / 折扣价: 133 加购物车

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5.1 This practice describes procedures applicable to both shop and field conditions. More comprehensive or precise measurements of the characteristics of complete systems and their components will generally require laboratory techniques and electronic equipment such as oscilloscopes and signal generators. Substitution of these methods is not precluded where appropriate; however, their usage is not within the scope of this practice.5.2 This document does not establish system acceptance limits, nor is it intended as a comprehensive equipment specification.5.3 While several important characteristics are included, others of possible significance in some applications are not covered.5.4 Since the parameters to be evaluated and the applicable test conditions must be specified, this practice shall be prescribed only by those familiar with ultrasonic NDT technology and the required tests shall be performed either by such a qualified person or under his supervision.5.5 Implementation may require more detailed procedural instructions in the format of the using facility.5.6 In the case of evaluation of a complete system, selection of the specific tests to be made should be done cautiously; if the related parameters are not critical in the intended application, then their inclusion may be unjustified. For example, vertical linearity may be irrelevant for a go/no-go test with a flaw gate alarm, while horizontal linearity might be required only for accurate flaw-depth or thickness measurement from the display screen.5.7 No frequency of system evaluation or calibration is recommended or implied. This is the prerogative of the using parties and is dependent on application, environment, and stability of equipment.5.8 Certain sections are applicable only to instruments having receiver gain controls calibrated in decibels (dB). While these may sometimes be designated “gain,” “attenuator,” or “sensitivity” on various instruments, the term “gain controls” will be used in this practice in referring to those which specifically control instrument receiver gain but not including reject, electronic distance-amplitude compensation, or automatic gain control.5.9 These procedures can generally be applied to any combination of instrument and search unit of the commonly used types and frequencies, and to most straight-beam examination, either contact or immersed. Certain sections are also compatible with angle-beam, wheel, delay-line, and dual-search unit techniques. Their use, however, should be mutually agreed upon and so identified in the test report.5.10 The validity of the results obtained will depend on the precision of the instrument display readings. This is assumed to be ±0.04 in. (±1 mm), yielding between 1 % and 2 % of full scale (fs) readability for available instrumentation having suitable screen graticules and display sharpness.1.1 This practice describes procedures for evaluating the following performance characteristics of ultrasonic pulse-echo examination instruments and systems: Horizontal Limit and Linearity; Vertical Limit and Linearity; Resolution - Entry Surface and Far Surface; Sensitivity and Noise; Accuracy of Calibrated Gain Controls. Evaluation of these characteristics is intended to be used for comparing instruments and systems or, by periodic repetition, for detecting long-term changes in the characteristics of a given instrument or system that may be indicative of impending failure, and which, if beyond certain limits, will require corrective maintenance. Instrument characteristics measured in accordance with this practice are expressed in terms that relate to their potential usefulness for ultrasonic testing. Instrument characteristics expressed in purely electronic terms may be measured as described in Guide E1324.1.2 Ultrasonic examination systems using pulsed-wave trains and A-scan presentation (rf or video) may be evaluated.1.3 The procedures are applicable to shop or field conditions; additional electronic measurement instrumentation is not required.1.4 This practice establishes no performance limits for examination systems; if such acceptance criteria are required, these must be specified by the using parties. Where acceptance criteria are implied herein, they are for example only and are subject to more or less restrictive limits imposed by customer's and end user's controlling documents.1.5 The specific parameters to be evaluated, conditions and frequency of test, and report data required must also be determined by the user.1.6 This practice may be used for the evaluation of a complete examination system, including search unit, instrument, interconnections, fixtures and connected alarm and auxiliary devices, primarily in cases where such a system is used repetitively without change or substitution. This practice is not intended to be used as a substitute for calibration or standardization of an instrument or system to inspect any given material. There are limitations to the use of standard reference blocks for that purpose.21.7 Required test apparatus includes selected test blocks and a precision external attenuator (where specified) in addition to the instrument or system to be evaluated.1.8 Precautions relating to the applicability of the procedures and interpretation of the results are included.1.9 Alternate procedures, such as examples described in this document, or others, may only be used with customer approval.1.10 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.11 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.12 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM F1089-18 Standard Test Method for Corrosion of Surgical Instruments Active 发布日期 :  1970-01-01 实施日期 : 

3.1 This test method provides corrosion test methodologies and means of evaluation that serve as indicators of proper material selection and proper processing by the manufacturer.NOTE 1: It is recommended that instruments be chemically passivated according to one of the treatments in Specification A967, electropolished according to Specification B912, or both, prior to evaluating the corrosion resistance according to this test method. The likelihood of failure may be higher for non-passivated instruments.1.1 This test method covers general test procedures and evaluation criteria for the corrosion resistance of new and reusable surgical instruments fabricated from stainless steel alloys, such as, but not limited to, those listed in Specification F899.1.2 Instruments containing stainless steel materials that are exclusive to the following shall use the boil test and the copper sulfate test: austenitic materials (Class 3), precipitation hardening materials (Class 5), and ferritic materials (Class 6) containing equal or greater than 16 % chromium.1.3 Instruments containing any of the following stainless steel materials shall use the boil test: martensitic materials (Class 4) and ferritic materials (Class 6) containing less than 16 % chromium.1.4 The copper sulfate test is used to detect the presence of free iron on the surface of materials.1.5 The copper sulfate test as described in 6.2 is not recommended for martensitic materials or for ferritic materials containing less than 16% chromium because these steels may give a positive indication irrespective of the presence or absence of anodic surface contaminants (see X1.5).1.6 The boil test is applicable to martensitic, austenitic, ferritic, and precipitation hardening materials to detect surface imperfections, free iron, or other anodic surface contaminants on stainless steel.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The mathematical and statistical techniques described in this guide support implementation of the calibration requirements of Practice D7282 and the guidance for uncertainty analysis given in Guide D8293. The guidance is intended for use either by qualified specialists at a radioanalytical laboratory or by developers of software for calibration of nuclear instruments.5.2 Applications for single-point calibrations might include:5.2.1 Alpha-particle spectrometry,5.2.2 Gas proportional counters used for thin sources with negligible attenuation, and5.2.3 Gamma-ray spectrometers used for single nuclides.5.3 Applications for calibration curves determined by LLS might include:5.3.1 Mass attenuation curves for gas proportional counters (polynomial), and5.3.2 Quench calibration curves for liquid scintillation counters (polynomial).5.4 Applications for calibration curves determined by NLLS might include:5.4.1 Gamma-ray spectrometry across a range of gamma-ray energies,5.4.2 Mass attenuation curves for gas proportional counters, and5.4.3 Quench calibration curves for liquid scintillation counters.5.5 Although this guide focuses on efficiency calibrations for nuclear instruments, the same general principles and paradigms should apply to other types of calibrations and to other instruments, as long as there are valid uncertainty models for the calibration data.1.1 This guide describes data analysis for efficiency calibrations of nuclear instruments using radioactive sources. It includes the calculation of the calibration parameters, evaluation and use of their uncertainties and covariances, and testing of the calibration data for outliers and overall lack of fit. It also provides guidelines for summarizing and reporting the results of a calibration.1.2 The instrument counting efficiency is assumed to be independent of the radiation emission rate.1.3 Guidance is provided for both single-point calibrations and calibration curves.1.4 The guidance presumes the existence of measurement uncertainty models to provide statistical weighting factors for the calibration data.1.5 This guide does not cover calibrations involving physically-based computer simulations.1.6 The system of units for this guide is not specified. Dimensional quantities in the guide are presented only as illustrations of calculation methods. The examples are not binding on products or test methods treated.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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