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5.1 This practice is for use by designers and specifiers, regulatory agencies, owners, contractors, and inspection organizations who are involved in rehabilitation of pressurized piping systems.1.1 This standard is intended to establish the minimum criteria necessary for use of a mechanically mixed, blended, epoxy barrier coating (AWWA Class I) that is applied to the interior of 1/2 in. (12.7 mm) to 36 in. (914.4 mm) metallic pipe or tube used in pressurized piping systems for corrosion protection and to improve flow rates. There is no restriction as to the developed length of the piping system other than the method of application (“blow through”, spin cast or hand sprayed) and the characteristics of the epoxy coating being applied but the manufacturer’s engineer shall be consulted for any limitations associated with this product, process and its application for the end user.1.2 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.1.3 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.1.4 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 PCRT Applications and Capabilities—PCRT has been applied successfully to a wide range of NDT applications in the manufacture and maintenance of metallic and non-metallic parts. Examples of anomalies detected are discussed in 1.1. PCRT has been shown to provide cost effective and accurate NDT solutions in many industries including automotive, aerospace, and power generation. Examples of successful applications currently employed in commercial use include, but are not limited to:(1) Silicon nitride bearing elements(2) Steel, iron, and aluminum rocker and control arms(3) Aircraft and industrial gas turbine engine components (blades, vanes, disks)(4) Cast cylinder heads and cylinder blocks(5) Sintered powder metal gears and clutch plates(6) Machined forged steel steering and transmission components (gears, shafts, racks)(7) Ceramic oxygen sensors(8) Silicon wafers(9) Gears, including those with induction hardened or carburized teeth(10) Ceramic matrix composite (CMC) material samples and components(11) Components with shot peened surfaces(12) Machined or rolled-formed fasteners(13) Components made with additive manufacturing(14) Aircraft landing gear, wheel, and brake components(15) Components made with metal injection molding5.2 General Approach and Equipment Requirements for PCRT via Swept Sine Input: 5.2.1 PCRT systems comprise hardware and software capable of inducing vibrations, recording the component response to the induced vibrations, and executing analysis of the data collected. Inputting a swept sine wave into the part has proven to be an effective means of introducing mechanical vibration and can be achieved with a high quality signal generator coupled with an appropriate active transducer in physical contact with the part. Collection of the part’s frequency response can be achieved by recording the signal generated by an appropriate passive vibration transducer. The software required to analyze the available data may include a variety of suitable statistical analysis and pattern recognition tools. Measurement accuracy and repeatability are extremely important to the application of PCRT.5.2.2 Hardware Requirements—A swept sine wave signal generator and response measurement system operating over the desired frequency range of the test part are required with accuracy better than 0.002 %. The signal generator should be calibrated to applicable industry standards. Transducers must be operable over same frequency range. Three transducers are typically used; one Drive transducer and two Receive transducers. Transducers typically operate in a dry environment, providing direct contact coupling to the part under examination. However, non-contacting response methods can operate suitably when parts are wet or oil-coated. Other than fixturing and transducer contact, no other contact with the part is allowed as these mechanical forces dampen certain vibrations. For optimal examination, parts should be placed precisely on the transducers (generally, ±0.062 in. (1.6 mm) in each axis provides acceptable results). The examination nest and cabling shall isolate the Drive from Receive signals and ground returns, so as to not produce (mechanical or electrical) cross talk between channels. Excessive external vibration or audible noise, or both, will compromise the measurements.5.3 Constraints and Limitations: 5.3.1 PCRT cannot separate parts based on visually detectable anomalies that do not affect the structural integrity of the part. It may be necessary to provide additional visual inspection of parts to identify these indications.5.3.2 Excessive process variation of parts may limit the sensitivity of PCRT. For example, mass/dimensional variations exceeding 5 % may cause PCRT to be unusable.5.3.3 Specific anomaly identification is highly unlikely. PCRT is a whole body measurement and differentiating between a crack and a void in the same location is generally not possible. It may be possible to differentiate some anomalies by using multiple patterns and training sets. The use of physics-based modeling and simulation to predict the resonance frequency spectrum of a component may also allow relationships between resonance frequencies and defect locations/characteristics to be established.5.3.4 PCRT will only work with stiff objects that provide resonances whose frequency divided by their width at half of the maximum amplitude (Q) are greater than 400 to 500. Although steel parts may be very stiff and perfectly reasonable to use for PCRT, steel foil would generally not be.5.3.5 While PCRT can be applied to painted and coated parts in many cases, the presence of some surface coatings such as vibration-absorbing materials and heavy oil layers may limit or preclude the application of PCRT.5.3.6 While PCRT can be applied to parts over a wide range of temperatures, it should not be applied to parts that are rapidly changing temperature. The part temperature should be stabilized before collecting resonance data.5.3.7 Misclassified parts in the teaching set, along with the presence of unknown anomalies in the teaching set, can significantly reduce the accuracy and sensitivity of PCRT.1.1 This practice describes a general procedure for using the process compensated resonance testing (PCRT) via swept sine input method for metallic or non-metallic parts to compare resonance patterns from a sample under test to reference teaching sets of known acceptable and targeted defect samples. The resonance pattern differences can be used to distinguish acceptable parts with normal process variation from parts with targeted material states and defects that will cause performance deficiencies. These material states and defects include, but are not limited to, cracks, voids, porosity, shrink, inclusions, discontinuities, grain and crystalline structure differences, density-related anomalies, heat treatment variations, material elastic property differences, residual stress, and dimensional variations. This practice is intended for use with instruments capable of exciting, measuring, recording, and analyzing multiple whole body, mechanical vibration resonance frequencies in acoustic or ultrasonic frequency ranges, or both.1.2 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.1.3 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.1.4 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 This test method allows for the measurement of the torque retention properties of container/continuous thread closure systems of various designs, materials, and manufacture, and is suitable for packaging development and engineering evaluation.5.2 This test method can be used for the evaluation of container/continuous thread closure systems under controlled conditions (where the application torque is known and the applied downward force to the closure is zero).5.3 This test method measures torque retention properties of container/continuous thread closure systems with the use of a non-automated, spring torque-meter (with either a dial indicator or a digital readout) or a torque wrench.1.1 These test methods evaluate the torque retention of continuous thread closures on containers, with matching finishes, for predetermined environmental conditions over time.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. 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 non-conformance with the standard.NOTE 1: The SI unit system is the recommended system.1.3 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.1.4 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 In the test method, coolants generally will be distinguished that have a tendency to foam excessively from those that are suitable for further evaluation to determine performance in actual service.NOTE 1: In use, the foaming tendency of a coolant solution may be increased by service aging or contamination. A properly functioning pressure cap will tend to suppress foaming in coolant solutions.1.1 This test method covers a simple glassware test for evaluating the tendency of non-aqueous engine coolants to foam under laboratory controlled conditions of aeration and temperature.1.2 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.3 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. For specific warning statements, see 7.2 and 7.3.1.4 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 specification covers Grade 82 unleaded aviation gasoline for use only in engines and associated aircraft that are specifically approved by the engine and aircraft manufacturers, and certified by the National Certifying Agencies to use this fuel. Aviation gasoline shall consist of blends of refined hydrocarbons derived from crude petroleum, natural gasoline or blends thereof, with specific aliphatic ethers, synthetic hydrocarbons, or aromatic hydrocarbons, and when applicable, methyl tertiarybutyl ether (MTBE). They may also contain antioxidants (oxidation inhibitors), metal deactivators, corrosion inhibitors, and fuel system icing inhibitors. The gasoline shall be tested and conform accordingly to the following property requirements: lean mixture knock value and motor method octane number; color; blue and red dye content; distillation temperature at % evaporated, end point, and residue content; distillation recovery; distillation loss; net heat of combustion; freezing point; vapor pressure; lead content; copper strip corrosion; sulfur content; potential gum; and alcohols and ether content (aliphatic ethers, methanol, and ethanol).1.1 This specification covers Grades UL82 and UL87 unleaded aviation gasolines, which are defined by this specification and are only for use in engines and associated aircraft that are specifically approved by the engine and aircraft manufacturers, and certified by the National Certifying Agencies to use these fuels. Components containing hetro-atoms (oxygenates) may be present within the limits specified.1.2 A fuel may be certified to meet this specification by a producer as Grade UL82 or UL87 aviation gasoline only if blended from component(s) approved for use in these grades of aviation gasoline by the refiner(s) of such components, because only the refiner(s) can attest to the component source and processing, absence of contamination, and the additives used and their concentrations. Consequently, reclassifying of any other product to Grade UL82 or Grade UL87 aviation gasoline does not meet this specification.1.3 Appendix X1 contains an explanation for the rationale of the specification. Appendix X2 details the reasons for the individual specification requirements.1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.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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5.1 This test method is an indicator of the wear characteristics of non-petroleum and petroleum hydraulic fluids operating in a constant volume vane pump. Excessive wear in vane pumps could lead to malfunction of hydraulic systems in critical applications.1.1 This test method covers a constant volume vane pump test procedure operated at 1200 r/min and 13.8 MPa.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 Exception—There are no SI equivalents for the inch fasteners and inch O-rings that are used in the apparatus in this test method.1.2.2 Exception—In some cases English pressure values are given in parentheses as a safety measure.1.3 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.1.4 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 specification covers requirements and test methods for materials, dimensions, workmanship, impact resistance, pipe stiffness, flattening, buckling, tensile strength of seam, joint systems, perforations, and markings for steel reinforced thermoplastic pipe and fittings. The steel reinforced, spirally formed thermoplastic pipes are intended for use in underground applications where soil provides support for their flexible walls. These pipes will be used for gravity flow and non-pressure applications, such as storm sewers, sanitary sewers, industrial waste applications and drainage pipes. The pipe dimensions, pipe stiffness, flattening, impact resistance, tensile strength of seam, and joint tightness shall be tested to meet the requirements prescribed.1.1 This specification covers requirements and test methods for materials, dimensions, workmanship, impact resistance, pipe stiffness, flattening, buckling, tensile strength of seam, joint systems, perforations, and markings for steel reinforced thermoplastic pipe and fittings of nominal sizes 8 in. [200 mm] through 120 in. [3000 mm]. The steel reinforced, spirally formed thermoplastic pipes governed by this standard are intended for use in underground applications where soil provides support for their flexible walls. These pipes will be used for gravity flow and non-pressure applications, such as storm sewers, sanitary sewers, industrial waste applications and drainage pipes.1.2 Units—The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text 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 non-conformance with the standard.1.3 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.1.4 There is no similar or equivalent ISO standard.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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This specification covers test methods and requirements for dual wall polypropylene pipe and fittings. These requirements are intended to provide pipe and fittings suitable for underground use for nonpressure storm sewer systems. This specification also covers pipe and fittings with an interior smooth wall and an annular corrugated profile outer wall.1.1 This specification covers requirements and test methods for dual wall polypropylene pipe and fittings. The nominal inside diameters covered are 12 to 60 in. [300 to 1500 mm].1.2 The requirements of this specification are intended to provide pipe and fittings suitable for underground use for non-pressure storm sewer systems. Pipe and fittings produced in accordance with this specification shall be installed in compliance with Practice D2321.1.3 This specification covers pipe and fittings with an interior smooth wall and an annular corrugated profile outer wall (Fig. 1).FIG. 1 Interior Smooth Wall and an Annular Corrugated Profile Outer Wall1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. 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 non-conformance with the standard.1.5 The following precautionary statement caveat pertains only to the test method portion, Section 8, of this specification. 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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5.1 This test method determines the ignitability of materials in single or multiple layers.5.1.1 Material performance shall be determined from the ignitability of the specimen(s) and shall be reported as a probability of ignition at various incident energy levels.5.1.2 Materials which meet the flame resistance requirements of Specification F1506 do not require testing by this test method unless the mechanism of passing Specification F1506 involves melting and escape from the flame source (for example, coated fabrics, certain rainwear fabrics).5.2 This test method maintains the specimen in a static, vertical position and does not involve movement except that resulting from the exposure.5.3 This test method specifies a standard set of exposure conditions. Different exposure conditions may produce different results. In addition to the standard set of exposure conditions, other conditions representative of the expected hazard may be used.1.1 This test method is used to identify materials that are ignitable and that can continue to burn when exposed to an electric arc, and determines (a) the incident exposure energy that causes ignition, and (b) the probability of ignition.1.2 The specimens tested in this test method are materials fabricated in the form of shirts.1.3 This test method shall be used to measure and describe the properties of materials, products, or assemblies in response to convective and radiant energy generated by an electric arc under controlled laboratory conditions.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. 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 non-conformance with the standard.1.5 This standard shall not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.1.6 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.1.7 For specific precautions, see Section 7.

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4.1 This test method shall be used to determine if a chemical intended for use as a non-food contact sanitizer or as a one-step cleaner-sanitizer provides percent reductions of the selected test organisms on treated carriers as compared to control.1.1 This test method is used to evaluate the antimicrobial efficacy of sanitizers on precleaned, inanimate, hard, nonporous, non-food contact surfaces against Staphylococcus aureus, or Klebsiella pneumoniae or Klebsiella aerogenes, or a combination thereof. Appropriate modifications to the method may be required when testing organisms not specified herein. When utilizing test surfaces not described herein (see Test Method E2274) or when evaluating spray-based or towelette-based antimicrobial products, modifications may also be required.1.2 This test method may also be used to evaluate the antimicrobial efficacy of one-step cleaner-sanitizer formulations recommended for use on lightly soiled, inanimate, nonporous, non-food contact surfaces.1.3 It is the responsibility of the investigator to determine whether Good Laboratory Practices (GLP) are required and to follow them where appropriate (see section 40 CFR, 160 or as revised.)1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard may involve hazardous materials, chemicals and microorganisms and should be performed only by persons who have had formal microbiological training. 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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5.1 This test method is useful for characterizing the flow behavior of asphalt emulsion residues and non-Newtonian asphalts. However, since non-Newtonian viscosity values depend on the level of shearing stress, its duration, and the shear history of the material, a non-Newtonian viscosity is not a unique material property. Instead, it is a parameter which is characteristic of the fluid-viscometer system under the conditions of the measurement procedure. Therefore, comparisons of non-Newtonian material behavior should only be made using apparent viscosities determined in similar viscometers under similar conditions of shearing stress and stress history. Procedures of sample preparation are especially important for repeatability or reproducibility of test results.NOTE 3: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capacity, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method describes procedures primarily designed to determine the apparent viscosities of residues obtained by distilling asphalt emulsions according to Test Method D6997. It is also recommended for use on non-Newtonian asphalts at any temperature within the capability of the apparatus. This test method is useful in characterizing rheological properties of non-Newtonian asphalts as a function of shear rate under the conditions of the test method. This test is run in straight open-end tube viscometers, normally at 60 °C, but is suitable for use at other temperatures. It is applicable over the range from 5 to 50 000 Pa·s.NOTE 1: The precision for this test method is based on determinations made at 60 °C.1.2 The values stated in SI units are to be regarded as the standard, except in reference to viscometer constant or calibration factor (K).1.3 Warning— Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury or its vapor may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheets (MSDS) for details and the EPA’s website (www.epa.gov/mercury/faq.htm) for additional information. Users should be aware that selling mercury, mercury-containing products, or both, in your state may be prohibited by state law.1.4 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of 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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This specification covers steel joint bars of low-carbon, medium-carbon, and high-carbon grades (Grades 1, 2, and 3) for railway applications. Steel shall be made through basic-oxygen or electric-furnace processes and cast through continuous process or in ingots. An analysis of each heat or cast shall be made to determine the percentage compositions of carbon, manganese, phosphorus, and sulfur. Tension test shall also be made to conform to specified tensile strength and elongation values. Guidelines on the dimensions and physical variations of joint bars are given. Inspection, rejection, rehearing, certification, and product marking procedures are cited.1.1 This specification covers steel joint bars for connecting steel rails in mine, industrial, and standard railroad track.1.2 Three grades of joint bars are defined for applications where non-heat treated bars are suitable:1.2.1 Grade 1, low-carbon, primarily for industrial and mine use.1.2.2 Grade 2, medium-carbon, primarily for industrial and mine use.1.2.3 Grade 3, high-carbon, for general use in standard railroad track. They may be used in the production of insulated track joints.1.3 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.1.4 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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1.1 A non-aqueous engine coolant is a glycol, diol, triol, or mixtures thereof, based heat transfer fluid containing less than 1.0 % water when formulated and intended for final use without dilution with water. (Definition from Terminology D4725.)1.2 This specification covers the requirements for fully formulated non-aqueous glycol base coolants for cooling systems of heavy-duty engines. These coolants will function effectively during both winter and summer to provide protection against corrosion, cavitation, freezing, boiling, and excessive viscosity.1.3 This specification is intended to cover the requirements for non-aqueous engine coolants prepared from virgin glycols, diols, or triols, or mixtures thereof.1.4 Coolants meeting this specification exhibit very low vapor pressures under all operating conditions, thereby avoiding the creation and collapse of coolant vapor, the primary cause of pump and cylinder liner cavitation erosion. They may additionally contain additives that provide traditional anti-cavitation erosion coatings but there is no requirement that they must. Non-aqueous engine coolants usually contain one or more carboxylates and do not normally contain nitrites. It is suggested that coolant testing be undertaken at normal manufacturer’s recommended intervals to monitor degradation products. The low vapor pressures inherent in coolants that meet this specification also provide protection from hot surface scaling, as liquid coolant is in contact with all hot metal surfaces of the engine cooling system at all times.1.5 Water is a contaminant to non-aqueous engine coolants and it is suggested that water content be tested periodically with test strips to ideally keep water content of the coolant at 3 % or less. Increases in water cause an undesirable drop in the boiling point. It is instructive that the glassware corrosion testing per this specification is conducted at 6 % corrosive water.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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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This specification covers gray iron castings exposed to elevated temperatures for non-pressure containing parts such as grate bars, stoker links, stoker parts, oil still furnace parts, firebox parts, ingot molds, glass molds, caustic pots, and metal melting pots. The three classes of gray iron covered here are: Class I, possessing superior thermal shock resistance; Class II, possessing average thermal shock resistance and moderately good tensile strength; and Class III, possessing a higher tensile strength than either Classes I or II. It is the intention of this specification to classify the irons in accordance with their carbon content equivalent, wherein the equation for its calculation is given herein. 1.1 This specification covers three classes of gray iron suitable for castings exposed to temperatures encountered in such service as grate bars, stoker links, stoker parts, oil still furnace parts, firebox parts, ingot molds, glass molds, caustic pots, and metal melting pots. Note 1: This specification is general, covering cast irons normally used for the above types of service, at temperatures as high as 1400 °F (760 °C). It is not intended to imply that all three classes are suitable throughout this entire temperature range without regard to actual service stresses. Some are suitable for long service at the lower temperatures only, unless low stresses are involved. 1.2 The three classes of gray iron covered by this specification are as follows: 1.2.1 Class I, possessing superior resistance to thermal shock, 1.2.2 Class II, possessing average resistance to thermal shock and a moderately good tensile strength (tensile strengths above 30 000 psi (207 MPa) may be expected), and 1.2.3 Class III, possessing a higher tensile strength than either Class I or II (tensile strengths as high as 40 000 psi (276 MPa) may be expected). 1.3 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. 1.4 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 Because there are a number of choices in this test method that depend on different applications and system configurations, it is the responsibility of the user of this test method to specify the details and protocol of an individual system power measurement prior to the beginning of a measurement.5.2 Unlike device-level measurements that report performance at a fixed device temperature of 25 °C, such as Test Methods E1036, this test method uses regression to a reference ambient air temperature.5.2.1 System power values calculated using this test method are therefore much more indicative of the power a system actually produces compared with reporting performance at a relatively cold device temperature such as 25 °C.5.2.2 Using ambient temperature reduces the complexity of the data acquisition and analysis by avoiding the issues associated with defining and measuring the device temperature of an entire photovoltaic system.5.2.3 The user of this test method must select the time period over which system data are collected, and the averaging interval for the data collection within the constraints of 8.3.5.2.4 It is assumed that the system performance does not degrade or change during the data collection time period. This assumption influences the selection of the data collection period because system performance can have seasonal variations.5.3 The irradiance shall be measured in the plane of the modules under test. If multiple planes exist (particularly in the case of rolling terrain), then the plane or planes in which irradiance measurement will occur must be reported with the test results. In the case where this test method is to be used for acceptance testing of a photovoltaic system or reporting of photovoltaic system performance for contractual purposes, the plane or planes in which irradiance measurement will occur must be agreed upon by the parties to the test prior to the start of the test.NOTE 1: In general, the irradiance measurement should occur in the plane in which the majority of modules are oriented. Placing the measurement device in a plane with a larger tilt than the majority will cause apparent under-performance in the winter and over-performance in the summer.5.3.1 The linear regression results will be most reliable when the measured irradiance, ambient temperature, and wind speed data during the data collection period are distributed around the reporting conditions. When this is not the case, the reported power will be an extrapolation to the reporting conditions.5.4 Accumulation of dirt (soiling) on the photovoltaic modules can have a significant impact on the system rating. The user of this test may want to eliminate or quantify the level of soiling on the modules prior to conducting the test.5.5 Repeated regression calculations on the same system to the same RC and using the same type of irradiance measurement device over successive data collection periods can be used to monitor performance changes as a function of time.5.6 Capacity determinations are power measurements and are adequate to demonstrate system completeness. However, a single capacity measurement does not provide sufficient information to project the energy generation potential of the system over time. Factors that may affect energy generation over time include: module power degradation, inverter clipping and overloading, shading, backtracking, extreme orientations, and filtering criteria.1.1 This test method provides measurement and analysis procedures for determining the capacity of a specific photovoltaic system built in a particular place and in operation under natural sunlight.1.2 This test method is used for the following purposes:1.2.1 Acceptance testing of newly installed photovoltaic systems,1.2.2 Reporting of dc or ac system performance, and1.2.3 Monitoring of photovoltaic system performance.1.3 This test method should not be used for:1.3.1 Testing of individual photovoltaic modules for comparison to nameplate power ratings,1.3.2 Testing of individual photovoltaic modules or systems for comparison to other photovoltaic modules or systems, and1.3.3 Testing of photovoltaic systems for the purpose of comparing the performance of photovoltaic systems located in different places.1.4 In this test method, photovoltaic system power is reported with respect to a set of reporting conditions (RC) including solar irradiance in the plane of the modules, ambient temperature, and wind speed (see Section 6). Measurements under a variety of reporting conditions are allowed to facilitate testing and comparison of results.1.5 This test method assumes that the solar cell temperature is directly influenced by ambient temperature and wind speed; if not the regression results may be less meaningful.1.6 The capacity measured according to this test method should not be used to make representations about the energy generation capabilities of the system.1.7 This test method is not applicable to concentrator photovoltaic systems; as an alternative, Test Method E2527 should be considered for such systems.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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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