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1 Scope 1.1 This Standard covers manual transfer panels having maximum ratings of 250 V, 60 A, for use in non-hazardous locations in accordance with the Canadian Electrical Code, Part I. 1.2 This Standard covers manual transfer panels that are inte

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3.1 This practice shall be used when ultrasonic inspection is required by the order or specification for inspection purposes where the acceptance of the forging is based on limitations of the number, amplitude, or location of discontinuities, or a combination thereof, which give rise to ultrasonic indications.3.2 The acceptance criteria shall be clearly stated as order requirements.1.1 This practice for ultrasonic examination covers turbine and generator steel rotor forgings covered by Specifications A469/A469M, A470/A470M, A768/A768M, and A940/A940M. This practice shall be used for contact testing only.1.2 This practice describes a basic procedure of ultrasonically inspecting turbine and generator rotor forgings. It does not restrict the use of other ultrasonic methods such as reference block calibrations when required by the applicable procurement documents nor is it intended to restrict the use of new and improved ultrasonic test equipment and methods as they are developed.1.3 This practice is intended to provide a means of inspecting cylindrical forgings so that the inspection sensitivity at the forging center line or bore surface is constant, independent of the forging or bore diameter. To this end, inspection sensitivity multiplication factors have been computed from theoretical analysis, with experimental verification. These are plotted in Fig. 1 (bored rotors) and Fig. 2 (solid rotors), for a true inspection frequency of 2.25 MHz, and an acoustic velocity of 2.30 in./s × 105 in./s [5.85 cm/s × 105 cm/s]. Means of converting to other sensitivity levels are provided in Fig. 3. (Sensitivity multiplication factors for other frequencies may be derived in accordance with X1.1 and X1.2 of Appendix X1.)FIG. 1 Bored ForgingsNOTE 1: Sensitivity multiplication factor such that a 10 % indication at the forging bore surface will be equivalent to a 1/8 in. [3 mm] diameter flat bottom hole. Inspection frequency: 2.0 MHz or 2.25 MHz. Material velocity: 2.30 in./s × 105 in./s [5.85 cm/s × 105 cm/s].FIG. 2 Solid ForgingsNOTE 1: Sensitivity multiplication factor such that a 10 % indication at the forging centerline surface will be equivalent to a 1/8 in. [3 mm] diameter flat bottom hole. Inspection frequency: 2.0 MHz or 2.25 MHz. Material velocity: 2.30 in./s × 105 in./s [5.85 cm/s × 105 cm/s].FIG. 3 Conversion Factors to Be Used in Conjunction with Fig. 1 and Fig. 2 if a Change in the Reference Reflector Diameter is Required1.4 Considerable verification data for this method have been generated which indicate that even under controlled conditions very significant uncertainties may exist in estimating natural discontinuities in terms of minimum equivalent size flat-bottom holes. The possibility exists that the estimated minimum areas of natural discontinuities in terms of minimum areas of the comparison flat-bottom holes may differ by 20 dB (factor of 10) in terms of actual areas of natural discontinuities. This magnitude of inaccuracy does not apply to all results but should be recognized as a possibility. Rigid control of the actual frequency used, the coil bandpass width if tuned instruments are used, and so forth, tend to reduce the overall inaccuracy which is apt to develop.1.5 This practice for inspection applies to solid cylindrical forgings having outer diameters of not less than 2.5 in. [64 mm] nor greater than 100 in. [2540 mm]. It also applies to cylindrical forgings with concentric cylindrical bores having wall thicknesses of 2.5 [64 mm] in. or greater, within the same outer diameter limits as for solid cylinders. For solid sections less than 15 in. [380 mm] in diameter and for bored cylinders of less than 7.5 in. [190 mm] wall thickness the transducer used for the inspection will be different than the transducer used for larger sections.1.6 Supplementary requirements of an optional nature are provided for use at the option of the purchaser. The supplementary requirements shall apply only when specified individually by the purchaser in the purchase order or contract.1.7 This practice is expressed in both inch-pound units and in SI units; however, unless the purchase order or contract specifies the applicable M specification designation (SI units), the inch-pound units shall apply. The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the practice, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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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This practice establishes minimum recommended design practices for gas turbine generator lubricating oil systems to ensure that:3.1.1 Lubrication, control, and seal functions will be performed satisfactorily by the oil mutually acceptable to the parties concerned.3.1.2 Installation, cleaning, and flushing will be facilitated.3.1.3 Satisfactory system cleanliness can be maintained.3.1.4 Safe practices are observed.1.1 This practice covers the design of lubricating oil systems for gas turbine driven generator units 1000 kW and larger.1.1.1 The lubricating oil system is defined as that assembly which utilizes and circulates the turbine generator lubricating oil and furnishes pressurized oil for control and seal functions.1.2 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 and health practices and determine the applicability of regulatory limitations prior to use.

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ASTM D4248-98(2003) Standard Practice for Design of Steam Turbine Generator Oil Systems (Withdrawn 2008) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

The purpose of this guide for turbine generator oil systems is to ensure that:3.1.1 Lubrication, control, and sealing will be performed satisfactorily by the oil in a manner mutually acceptable to the parties concerned.3.1.2 Installation, cleaning, and flushing will be facilitated.3.1.3 Satisfactory system cleanliness can be maintained.3.1.4 Safe practices are observed.1.1 This practice is applicable to steam turbine-generator units and provides recommended practices for the design of the oil system.1.1.1 The oil system is defined as that assembly which uses and circulates the turbine-generator lubricating oil. The oil system generally includes high pressure, bearing, control, generator seal, and drain systems. The system may also include the supply and return lines for a boiler feed pump and hydraulic coupling.1.2 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 and health practices and determine the applicability of regulatory limitations prior to use.

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This specification covers vacuum-treated basic electric steel forgings for use in generator rotors. Steel materials shall be manufactured by vacuum degassing, heat treatment, rough machining, and boring. Heat and product analyses shall be carried out to examine conformation of the specimens with chemical compositions of carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, vanadium, and antimony. Forgings shall also go through tension, impact, and Charpy V-notch tests, and shall conform with the following tensile and notch toughness requirements: tensile strength, yield strength, elongation, reduction of area, FATT50, and Charpy absorbed energy. Nondestructive test methods such as ultrasonic and internal inspection shall be performed.1.1 This specification covers vacuum-treated basic electric steel forgings for generator rotors.1.2 Supplementary requirements are provided, both in this standard and in Specification A788/A788M, for use when additional testing, inspection or processing is required by the purchaser.1.3 The values stated in either inch-pound units or SI (metric) units are to be regarded separately as standard. Within the text and tables, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.4 Unless the order specifies the applicable “M” specification designation, the material shall be furnished to the inch-pound units.1.5 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.1.6 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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This test method covers the procedures for the standard practice of performing ultrasonic shear and longitudinal wave examinations on turbine-generator steel retaining rings. A pulsed reflection-type ultrasonic instrument shall be used for the tests. Scanning of steel specimens may be performed by either the contact (stationary) or immersion (rotating) methods, both of which may be executed in either the axial or circumferential directions. Tests shall be performed after specimens have gone through final processing and heat treatment for properties, and the circumferential and axial faces machined flat and parallel to one another. Also prior to testing, surface examinations shall be made for surface roughness and tears, loose scales, machining or grinding particles, paint, and other foreign and extraneous matter. Suitable couplant liquids, capable of conducting ultrasonic vibrations, shall be used to couple the transducer to test surfaces.1.1 This practice covers ultrasonic examination of turbine-generator retaining rings produced in accordance with Specifications A288 and A289/A289M with an inside diameter to wall thickness ratio equal to or greater than 5:1 and with wall thicknesses from 1 in. to 4 in. [25 mm to 102 mm].1.2 Forgings may be inspected by either the contact or the immersion methods, or combinations thereof, as agreed upon between the manufacturer and the purchaser.1.3 Supplementary requirements of an optional nature are provided for use at the option of the purchaser. The supplementary requirements shall apply only when specified individually by the purchaser in the purchase order or contract.1.4 This practice is expressed in inch-pound and SI units; however, unless the purchase order or contract specifies the applicable “M” specification designation (SI units), the inch-pound units shall apply. The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the practice, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.5 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.1.6 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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4.1 Computer simulation is known to be a very powerful analytical tool for both practitioners and researchers in the area of wood products and their applications in structural engineering. Complex structural systems can be analyzed by computer with the computer generating the system components, given the probability distribution of each component. Frequently the components are single boards for which a compatible set of strength and stiffness properties are needed. However, the entire structural simulation process is dependent upon the adequacy of the standard uniform number generator required to generate random observations from prescribed probability distribution functions.4.2 The technological capabilities and wide availability of microcomputers has encouraged their increased use for simulation studies. Tests of random number generators in commonly available microcomputers have disclosed serious deficiencies (1).3 Adequacy may be a function of intended end-use. This practice is concerned with generation of sets of random numbers, as may be required for simulations of large populations of material properties for simulation of complex structures. For more demanding applications, the use of packaged and pretested random number generators is encouraged.1.1 This practice gives a minimum testing procedure of computer generation routines for the standard uniform distribution. Random observations from the standard uniform distribution, RU, range from zero to one with every value between zero and one having an equal chance of occurrence.1.2 The tests described in this practice only support the basic use of random number generators, not their use in complex or extremely precise simulations.1.3 Simulation details for the normal, lognormal, 2-parameter Weibull and 3-parameter Weibull probability distributions are presented.1.4 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.See specific warning statement in 5.5.3.1.5 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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4.1 The weight per unit area measurement is an indication of the relative cleanliness or dirtiness of the boiler. It is used to determine the effectiveness of the boiler chemical treatment program and to determine the need for chemically cleaning the boiler systems. Allowing the internal deposition to accumulate unchecked will likely lead to boiler tube failures by mechanisms of under deposit corrosion and tube metal overheating.1.1 These test methods cover the determination of the weight per unit area of waterside deposits on heat-transfer surfaces of steam generator tubes. The following test methods are included:  SectionsTest Method A—Mechanical removal by scraper or vibrating tool-removed deposit weight method 7 to 16Test Method B—Chemical removal by solvent-tube weight loss method 17 to 27Test Method C—Mechanical removal by glass-bead blasting-tube weight loss method 28 to 371.2 Test Method A is a procedure generally applicable to deposits ranging from 1 to 100 g/ft2. The precision was determined in the collaborative study over the range of 16 to 76 g/ft2. This procedure allows the discretionary selection of the area on the tube to be sampled. The removed deposit allows for further chemical analysis.1.3 Test Method B is a procedure generally applicable to deposits ranging from 1 to 100 g/ft2. The precision was determined in a collaborative study over the range of 28 to 73 g/ft2. The procedure averages out the heavier and lighter deposited areas. The solvent solution produced allows for further chemical analysis.1.4 Test Method C is a procedure generally applicable to deposits ranging from 1 to 100 g/ft2. The precision was determined in a collaborative study over the range of 17 to 88 g/ft2. The procedure averages out the heavier and lighter deposited areas. The removed deposit does not allow for further chemical analysis.1.5 These test methods have been generally evaluated on the types of waterside deposits generally found on heat-transfer surfaces of steam generator tubes. It is the user’s responsibility to ensure the validity of these test methods for other types of deposits or high temperature scale.1.6 These methods are sometimes used for accumulated deposition in rifled steam generator tubes. Experience has shown that there is a significant difference in the deposition in the grooves and on the lands on some rifled steam generator tubes. The grooves have been shown to hold more deposit. Test Method B and Test Method C will average out this difference. In Method A the choice exists, either to choose to remove the deposition from the groove if it is visually determined to be more heavily deposited, or to remove equally over the grooves and lands. It is important that it be understood what choices were made and that the report reflect the choices made when using Test Method A on rifled steam generator tubes.1.7 There are some steam generator tubes where it is apparent that half of the tube is exposed to the flame from the external appearance, this side is typically called the fireside or hot side. The other half of the tube is not exposed to the flame from the external appearance is typically called the casing side or cold side. These test methods also require that the tube be split in half, so the tube is generally split along these lines. On these tubes it is generally found that more internal deposition exists on the fireside or hot side. Some users of these methods will determine the deposition only on side where it appears visually that more deposition exists. Some users will determine the deposition on both sides and report the results separately and some will average the two results. It is important that the user of the data be aware of the choices made and that the report of the results be specific.1.8 The values stated in either SI or inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.1.9 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.1.10 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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