微信公众号随时随地查标准

QQ交流1群(已满)

QQ群标准在线咨询2

QQ交流2群

购买标准后,可去我的标准下载或阅读

5.1 Significance of Thermal Resistance Measurements—Knowledge of the thermal resistance of new buildings is important to determine whether the quality of construction satisfies criteria set by the designer, by the owner, or by a regulatory agency. Differences in quality of materials or workmanship may cause building components not to achieve design performance.5.1.1 For Existing Buildings—Knowledge of thermal resistance is important to the owners of older buildings to determine whether the buildings should receive insulation or other energy-conserving improvements. Inadequate knowledge of the thermal properties of materials or heat flow paths within the construction or degradation of materials may cause inaccurate assumptions in calculations that use published data.5.2 Advantage of In-Situ Data—This practice provides information about thermal performance that is based on measured data. This may determine the quality of new construction for acceptance by the owner or occupant or it may provide justification for an energy conservation investment that could not be made based on calculations using published design data.5.3 Heat Flow Paths—This practice assumes that net heat flow is perpendicular to the surface of the building envelope component within a given subsection. Knowledge of surface temperature in the area subject to measurement is required for placing sensors appropriately. Appropriate use of infrared thermography is often used to obtain such information. Thermography reveals nonuniform surface temperatures caused by structural members, convection currents, air leakage, and moisture in insulation. Practices C1060 and C1153 detail the appropriate use of infrared thermography. Note that thermography as a basis for extrapolating the results obtained at a measurement site to other similar parts of the same building is beyond the scope of this practice.5.4 User Knowledge Required—This practice requires that the user have knowledge that the data employed represent an adequate sample of locations to describe the thermal performance of the construction. Sources for this knowledge include the referenced literature in Practice C1046 and related works listed in Appendix X2. The accuracy of the calculation is strongly dependent on the history of the temperature differences across the envelope component. The sensing and data collection apparatuses shall have been used properly. Factors such as convection and moisture migration affect interpretation of the field data.5.5 Indoor-Outdoor Temperature Difference—The speed of convergence of the summation technique described in this practice improves with the size of the average indoor-outdoor temperature difference across the building envelope. The sum of least squares technique is insensitive to indoor-outdoor temperature difference, to small and drifting temperature differences, and to small accumulated heat fluxes.5.6 Time-Varying Thermal Conditions—The field data represent varying thermal conditions. Therefore, obtain time-series data at least five times more frequently than the most frequent cyclical heat input, such as a furnace cycle. Obtain the data for a long enough period such that two sets of data that end a user-chosen time period apart do not cause the calculation of thermal resistance to be different by more than 10 %, as discussed in 6.4.5.6.1 Gather the data over an adequate range of thermal conditions to represent the thermal resistance under the conditions to be characterized.NOTE 2: The construction of some building components includes materials whose thermal performance is dependent on the direction of heat flow, for example, switching modes between convection and stable stratification in horizontal air spaces.5.7 Lateral Heat Flow—Avoid areas with significant lateral heat flow. Report the location of each source of temperature and heat flux data. Identify possible sources of lateral heat flow, including a highly conductive surface, thermal bridges beneath the surface, convection cells, etc., that may violate the assumption of heat flow perpendicular to the building envelope component.NOTE 3: Appropriate choice of heat flow sensors and placement of those sensors can sometimes provide meaningful results in the presence of lateral heat flow in building components. Metal surfaces and certain concrete or masonry components may create severe difficulties for measurement due to lateral heat flow.5.8 Light- to Medium-Weight Construction—This practice is limited to light- to medium-weight construction that has an indoor temperature that varies by less than 3 K. The heaviest construction to which this practice applies would weigh 440 kg/m2, assuming that the massive elements in building construction all have a specific heat of about 0.9 kJ/kg K. Examples of the heaviest construction include: (1) a 390-kg/m2 wall with a brick veneer, a layer of insulation, and concrete blocks on the inside layer or (2) a 76-mm concrete slab with insulated built-up roofing of 240 kg/m2. Insufficient knowledge and experience exists to extend the practice to heavier construction.5.9 Heat Flow Modes—The mode of heat flow is a significant factor determining R-value in construction that contains air spaces. In horizontal construction, air stratifies or convects, depending on whether heat flow is downwards or upwards. In vertical construction, such as walls with cavities, convection cells affect determination of R-value significantly. In these configurations, apparent R-value is a function of mean temperature, temperature difference, and location along the height of the convection cell. Measurements on a construction whose performance is changing with conditions is beyond the scope of this practice.1.1 This practice covers how to obtain and use data from in-situ measurement of temperatures and heat fluxes on building envelopes to compute thermal resistance. Thermal resistance is defined in Terminology C168 in terms of steady-state conditions only. This practice provides an estimate of that value for the range of temperatures encountered during the measurement of temperatures and heat flux.1.2 This practice presents two specific techniques, the summation technique and the sum of least squares technique, and permits the use of other techniques that have been properly validated. This practice provides a means for estimating the mean temperature of the building component for estimating the dependence of measured R-value on temperature for the summation technique. The sum of least squares technique produces a calculation of thermal resistance which is a function of mean temperature.1.3 Each thermal resistance calculation applies to a subsection of the building envelope component that was instrumented. Each calculation applies to temperature conditions similar to those of the measurement. The calculation of thermal resistance from in-situ data represents in-service conditions. However, field measurements of temperature and heat flux may not achieve the accuracy obtainable in laboratory apparatuses.1.4 This practice permits calculation of thermal resistance on portions of a building envelope that have been properly instrumented with temperature and heat flux sensing instruments. The size of sensors and construction of the building component determine how many sensors shall be used and where they should be placed. Because of the variety of possible construction types, sensor placement and subsequent data analysis require the demonstrated good judgement of the user.1.5 Each calculation pertains only to a defined subsection of the building envelope. Combining results from different subsections to characterize overall thermal resistance is beyond the scope of this practice.1.6 This practice sets criteria for the data-collection techniques necessary for the calculation of thermal properties (see Note 1). Any valid technique may provide the data for this practice, but the results of this practice shall not be considered to be from an ASTM standard, unless the instrumentation technique itself is an ASTM standard.NOTE 1: Currently only Practice C1046 can provide the data for this practice. It also offers guidance on how to place sensors in a manner representative of more than just the instrumented portions of the building components.1.7 This practice pertains to light-through medium-weight construction as defined by example in 5.8. The calculations apply to the range of indoor and outdoor temperatures observed.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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

This specification covers minimum material requirements, and safety precautions in application, for adhesives to bond thermal insulation duct liner on the interior surfaces of sheet metal air conditioning ducts; and for coating exposed edges and joints of duct liner thermal insulation to minimize erosion of insulation fibers by air movement. Adhesives shall be classified as follows: Type I; Type II; Type III; and Type IV. The following test methods shall be performed: bonding strength; bond retention after heat aging; flame spread and smoke developed; edge-burning test; storage stability; and precision and bias.1.1 This specification covers minimum material requirements, and safety precautions in application, for adhesives to bond thermal insulation duct liner on the interior surfaces of sheet metal air conditioning ducts; and for coating exposed edges and joints of duct liner thermal insulation to minimize erosion of insulation fibers by air movement.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. For specific precautionary statements, see Sections 7 and 9.1.4 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.

定价: 515元 / 折扣价: 438 加购物车

在线阅读 收 藏

5.1 Solid lubricant coatings are applied to surfaces that are exposed to heat and cold to such a degree that in many cases liquid lubricants are not practical. Adherence under these conditions is mandatory to preserve the bearing surfaces during sliding motion.1.1 This test method covers the measurement of the resistance of dry solid film lubricants to deterioration when subjected to temperature extremes.1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.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.

定价: 515元 / 折扣价: 438 加购物车

在线阅读 收 藏

5.1 Different combinations of varnishes and film-insulated magnet wire behave differently when exposed to elevated temperatures. This includes different varnishes tested with the same film-insulated magnet wire and a single varnish tested with different film-insulated magnet wire.5.2 This test method is used to determine the effect on the electrical properties of a varnish applied to film-insulated magnet wire when the combination is exposed to prescribed elevated temperatures.1.1 This test method covers the determination of the thermal endurance characteristics of electrical insulating varnishes and film-insulated magnet wire in combination.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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.NOTE 1: This test method is equivalent to IEC 60172.1.4 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.

定价: 515元 / 折扣价: 438 加购物车

在线阅读 收 藏

5.1 This test method provides a means to evaluate the resistance to particle shedding of a thermal spray coating. Such particle shedding might occur during surgical insertion of an implant or as the result of micromotion of the implant after insertion.5.2 This abrasion test method may be useful for quality control analysis of a coating, and it can be used to evaluate the effects of processing variables, such as substrate preparation before coating, surface texture, coating technique variables, or postcoating treatments, any of which may influence the susceptibility of the coating to particle shedding.5.3 This abrasion test method is for flat plate-shaped specimens of a size sufficient that the wheels of the abrader do not leave the surface of the specimen. It is not recommended for devices with other shapes or sizes.1.1 This test method quantifies the abrasion resistance of metallic coatings produced by thermal spray processes on flat metallic surfaces. It is intended as a means of characterizing coatings used on surgical implants.1.2 This test uses the Taber Abraser,2 which generates a combination of rolling and rubbing to cause wear to the coating surface. Wear is quantified as cumulative weight loss.1.3 This test method is limited to flat, rigid specimens that do not react significantly with water and do not undergo a phase transformation or chemical reaction between room temperature and 100 °C in air.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 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

5.1 This test method may be used for the acceptance testing of commercial shipments of yarns and cords. Caution is advised because yarn and cord may contract in length over a period of time due to room temperature retraction. Thermal shrinkage values are reduced proportionately by the amount of room temperature retraction.NOTE 1: Experience, especially with nylon, shows that yarn retraction, which may be observed directly as shortening of length (or indirectly as denier increase), will occur in unrestrained yarn or cord that is not at equilibrium (equilibrium in this case being defined as essentially zero thermal shrinkage yarn or fully relaxed yarn). Normally, retractive forces are present in most wound packages of yarn and cord; thus, unrestrained yarn near the surface is likely, with time, to undergo some retraction. After retraction, such yarns exhibit lower thermal shrinkage values than yarn or cord deeper within the package. The opposite condition of yarn on the surface exists with yarn or cord wound against or near a rigid package core, such as a metal or hardwood wind-up spool. Such core yarn or cord cannot move against this restraint, and thus, will exhibit thermal shrinkage values even several weeks later near to those which were measured immediately from the surface of the freshly wound package. Elevated humidity will accelerate retraction of unrestrained yarn, but moisture content in itself will have little influence on thermal shrinkage. Exposure of untensioned skeins of yarn or cord to 95 to 100 % relative humidity at room temperature for two days and reconditioning under standard laboratory conditions will cause most of the room temperature retraction that is possible within a sample to occur.5.1.1 In case of differences of practical significance in reported test results from two or more laboratories conduct comparative tests to determine if there is a statistical bias between them. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of material of the type in question. The test specimens then should be assigned randomly in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and a probability level chosen by the parties before the testing is begun. If a bias is found, either its cause must be found and corrected, or future test results must be adjusted in consideration of the known bias.5.2 Thermal shrinkage of nylon, polyester, and other fibers is related to the polymer of origin and its manipulation in processing. Thermal shrinkage measurement can be used to control product uniformity.5.3 The level of thermal shrinkage is critical in the user's subsequent operations. For example it can affect the drumset (original length of cord) required in tire building to produce a finished, final tire of a particular size.5.4 Thermal shrinkage is critical to final shape and size of fiber reinforced articles. For example, thermal shrinkage affects final size of V-belts and their ability to maintain tension while running.5.5 This test method is similar to the procedures of Test Methods D885/D885M for the determination of thermal shrinkage of yarns and cords. Shrinkage is measured while the specimen is within an oven and tensioned as specified in Test Methods D885/D885M; however, there are enough vagaries among different units of apparatus for measurement of thermal shrinkage that numerical equivalence between units of different design should not be assumed, even under the same nominal conditions.1.1 This test method covers the measurement of shrinkage of yarns and cords when exposed in a thermal shrinkage oven.1.2 This test method is applicable to yarns and cords made of nylon, polyester, and other polymers not detrimentally affected by the temperature used and with linear densities in the range from 20 to 700 tex [180 to 6300 denier].1.2.1 Yarns or cords for testing may be taken from yarn or cord packages or from fabrics.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. 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. Referee decisions are to use SI units.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. Specific hazard statements are given in Section 8.1.5 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

5.1 Manufacturers of carpet need to monitor emissions of VOCs to assess the environmental impact of their products indoors. These results are also used to demonstrate compliance with VOC emission limits for individual VOCs.5.2 These data are also used to understand which VOCs are emitted from a product or material and to measure the magnitude of those emissions.5.3 Emission data may be used to compare different lots of carpet of the same materials of construction, or carpets composed of different materials of construction, in order to develop products with lower emissions and lower potential environmental impact.5.4 This test method should be used in conjunction with practices/guidelines for emissions testing such as Guide D5116, Practice D7143, Practice D7706, ISO 16000-9, and ISO 16000-10. These detail how to select and prepare samples and how and when to carry out emissions tests such that the concentration and profile of vapors in the exhaust air of the emission chamber/cell are representative of the product under test. This test method covers the sampling and analysis of volatile organic compounds in the exhaust gas from the chamber/cell using thermal desorption—compatible sorbent tubes and will provide the necessary analytical consistency to ensure that reproducible data is obtained for the analysis of identical vapor samples by different laboratories.1.1 This test method describes an analytical procedure for identifying and quantifying the masses of individual volatile organic compounds (individual VOCs or IVOCs) that are emitted into a flow of air from carpet specimens and collected on sorbent sampling tubes during emissions testing.1.2 This test method will be used in conjunction with a standard practice for sampling and preparing carpet specimens for emissions testing. If a specific chamber practice is not available for the carpet specimens, this test method should be used in conjunction with approved standard practices for emissions testing and sample preparation.1.3 When used in conjunction with standard practices for carpet specimen preparation and collection of vapor-phase emissions , this test method will provide a standardized means of determining the levels of IVOC in the exhaust stream of the emissions test chamber/cell. If this test method is used with a reliable practice for emissions testing, these IVOC levels can be used to determine the emission rate from a unit quantity (usually surface area) of the sample material under test.1.4 VOCs in the exhaust stream of an emissions test device are collected on thermal desorption tubes packed with a specific combination of sorbents using active (pumped) sampling. (See Practice D6196 for a more general description of vapor collection using pumped sampling onto sorbent tubes.) The samples are analyzed by thermal desorption (TD) with gas chromatography and mass spectrometry detection (GC/MS) and/or flame ionization detection (FID) depending upon the requirements of the specific materials emissions testing/certification protocol.1.5 This test method can be used for the measurement of most GC-compatible organic vapors ranging from the approximate volatility from n-hexane to n-hexadecane (that is, compounds with vapor pressures ranging from 16 kPa to 4 × 10-4 kPa at 25°C). Properties other than a compound’s vapor pressure such as affinity for the sorbent may need to be taken into account. Compounds with vapor pressures outside this range may or may not be quantifiable by this test method. However, qualitative data concerning the identity of a compound(s), outside the stated volatility range for quantitation, may still be useful to the user. This test method can be applied to analytes over a wide concentration range—typically 1 μg/m3 to 1 mg/m3 concentration of vapor in the exhaust air from the emission cell or chamber.1.6 This test method is not capable of quantifying all compounds which are emitted from carpets. See the appropriate test practices/methods for determining other compounds that are not amenable to analysis by gas chromatography (that is, Test Method D5197 for the determination of aldehydes).1.7 Units—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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

5.1 Uranium hexafluoride used to produce nuclear fuel must meet certain criteria for its isotopic composition as described in Specifications C787 and C996.1.1 This method applies to the determination of isotopic composition in hydrolyzed nuclear grade uranium hexafluoride. It covers isotopic abundance of  235U between 0.1 and 5.0 % mass fraction, abundance of  234U between 0.0055 and 0.05 % mass fraction, and abundance of   236U between 0.0003 and 0.5 % mass fraction. This test method may be applicable to other isotopic abundance providing that corresponding standards are available.1.2 This test method can apply to uranyl nitrate solutions. This can be achieved either by transforming the uranyl nitrate solution to a uranyl fluoride solution prior to the deposition on the filaments or directly by depositing the uranyl nitrate solution on the filaments. In the latter case, a calibration with uranyl nitrate standards must be performed.1.3 This test method can also apply to other nuclear grade matrices (for example, uranium oxides) by providing a chemical transformation to uranyl fluoride or uranyl nitrate solution.1.4 Units—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 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.

定价: 515元 / 折扣价: 438 加购物车

在线阅读 收 藏

5.1 Degradation of gear oils by oxidation or thermal breakdown, or both, can result in sludge buildup and render the oil unsuitable for further use as a lubricant.5.2 This is the only test method that employs glassware to measure the amount of sludge produced during oxidation and thermal degradation. This test method is a modification of Test Method D2893 which measures the viscosity increase and precipitation number of the oil stressed at 95 °C, but does not measure the amount of sludge formed.5.3 This test method can be used to evaluate the oxidation/thermal stability of gear oils. However, the test results may not correlate with the performance of gear oils in field service.1.1 This test method covers the determination of the oxidation characteristics of extreme pressure and non-extreme pressure gear oils and includes the quantitative determination of total sludge, viscosity change, and oil loss.NOTE 1: While the round-robin tests used ISO VG 220 extreme pressure gear oils for developing precision data, the test method can be extended to other viscosity grades and to non-extreme pressure gear oils. Refer to Classification D2422 for viscosity grades.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏
ASTM D7340-07(2023) Standard Practice for Thermal Conductivity of Leather Active 发布日期 :  1970-01-01 实施日期 : 

5.1 Part of the function of a shoe is to assist the foot in maintaining body temperature and to guard against large heat changes. The insulating property of a material used in shoe construction is dependent on porosity or the amount of air spaces present. A good insulating material has a low thermal conductivity value, k. The thermal conductivity value increases with an increase in moisture content since the k value for water is high, 0.0014 cal/s cm · °C (0.59 W/m·K).1.1 This practice is intended to determine the thermal conductivity of a sheet material. This practice is not limited to leather, but may be used for any poorly conductive material such as rubber, textile and cork associated with the construction of shoes.1.2 A constant heat source is sandwiched between two identical metal cylinders which are mounted with their axes vertical. A test specimen is placed on the top surface of the upper cylinder and a third identical metal cylinder is placed on top of the test specimen so that all the cylinders and the test specimen are concentrically aligned (see Fig. 1). The heat source is switched on and the temperatures of the three blocks allowed to reach equilibrium. The thermal conductivity of the test specimen is then determined from the steady-state temperatures of the three blocks, the exposed surface areas of the blocks and test specimen and the thickness of the test specimen.FIG. 1 SATRA Lees' Disc Thermal Conductivity Apparatus1.3 This practice does not apply to wet blue.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.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.

定价: 515元 / 折扣价: 438 加购物车

在线阅读 收 藏

5.1 Coefficients of linear expansion are required for design purposes and are used particularly to determine thermal stresses that can occur when a solid artifact composed of different materials may fail when it is subjected to a temperature excursion(s).5.2 Many new composites are being produced that have very low thermal expansion coefficients for use in applications where very precise and critical alignment of components is necessary. Push rod dilatometry such as Test Methods D696 and E228, and thermomechanical analysis methods such as Test Method E831 are not sufficiently precise for reliable measurements either on such material and systems, or on very short specimens of materials having higher coefficients.5.3 The precision of the absolute method allows for its use to:5.3.1 Measure very small changes in length;5.3.2 Develop reference materials and transfer standards for calibration of other less precise techniques;5.3.3 Measure and compare precisely the differences in coefficient of “matched” materials.5.4 The precise measurement of thermal expansion involves two parameters; change of length and change of temperature. Since precise measurements of the first parameter can be made by this test method, it is essential that great attention is also paid to the second, in order to ensure that calculated expansion coefficients are based on the required temperature difference. Thus in order to ensure the necessary uniformity in temperature of the specimen, it is essential that the uniform temperature zone of the surrounding furnace or environmental chamber shall be made significantly longer than the combined length of specimen and mirrors.5.5 This test method contains essential details of the design principles, specimen configurations, and procedures to provide precise values of thermal expansion. It is not practical in a method of this type to try to establish specific details of design, construction, and procedures to cover all contingencies that might present difficulties to a person not having the technical knowledge relating to the thermal measurements and general testing practice. Standardization of the method is not intended to restrict in any way further development of improved methodology.5.6 The test method can be used for research, development, specification acceptance and quality control and assurance.1.1 This test method covers the determination of linear thermal expansion of rigid solids using either a Michelson or Fizeau interferometer.1.2 For this purpose, a rigid solid is defined as a material which, at test temperature and under the stresses imposed by instrumentation, has a negligible creep, insofar as significantly affecting the precision of thermal length change measurements.1.3 It is recognized that many rigid solids require detailed preconditioning and specific thermal test schedules for correct evaluation of linear thermal expansion behavior for certain material applications. Since a general method of test cannot cover all specific requirements, details of this nature should be discussed in the particular material specifications.1.4 This test method is applicable to the approximate temperature range −150°C to 700°C. The temperature range may be extended depending on the instrumentation and calibration materials used.1.5 The precision of measurement of this absolute method (better than ±40 nm/(m·K)) is significantly higher than that of comparative methods such as push rod dilatometry (for example, Test Methods D696 and E228) and thermomechanical analysis (for example, Test Method E831) techniques. It is applicable to materials having low and either positive or negative coefficients of expansion (below 5 μm/(m·K)) and where only very limited lengths or thickness of other higher expansion coefficient materials are available.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 and health 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

This practice establishes the standard procedures for determining the material and physical properties for jacketing materials applied over thermal insulation on piping and equipment, including materials applied solely for physical protection, and materials applied as vapor retarders. This practice does not cover field applied mastics or barrier coatings and their attendant reinforcements, nor does it cover jackets for buried insulation systems. Jackets covered here are grouped into two types, each of which are subdivided further into grades and classes. Properties to which the jackets should conform to are permeance, tensile strength, puncture resistance, surface burning characteristics, flame resistance permeance, dimensional stability, fungi resistance, elevated temperature and humidity resistance, and thermal integrity.1.1 This practice covers jackets applied over thermal insulation on piping and equipment, including materials applied solely for physical protection, and materials applied as vapor retarders.1.2 This practice provides material and physical requirements, or both, for jackets. Guidance in selecting the proper jacket for a given application can be found in Guide C1423.1.3 This practice does not cover field applied mastics or barrier coatings and their attendant reinforcements, nor does it cover jackets for buried insulation systems.1.4 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.1.5 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 and health practices and determine the applicability of regulatory limitations prior to use.

定价: 0元 / 折扣价: 0

在线阅读 收 藏

5.1 A major factor affecting the life of insulating materials is thermal degradation. It is possible that other factors, such as moisture and vibration, will cause failures after the material has been weakened by thermal degradation.5.2 Electrical insulation is effective in electrical equipment only as long as it retains its physical and electrical integrity. The following are potential indicators of thermal degradation: weight change, porosity, crazing, and generally a reduction in flexibility. Thermal degradation is usually accompanied by an ultimate reduction in dielectric breakdown.5.3 This test method is useful in determining the thermal endurance of coating powders applied over a copper or aluminum substrate material.1.1 This test method provides a procedure for evaluating thermal endurance of coating powders by determining the length of aging time at selected elevated temperatures required to achieve dielectric breakdown at room temperature at a pre-determined proof voltage. Thermal endurance is expressed in terms of a temperature index.1.2 This test method is applicable to insulating powders used over a substrate material of copper or aluminum.1.3 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 are not necessarily exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems is likely to result in non-conformance with the standard.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. Specific precautionary statements are given in Section 7.1.5 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

3.1 This test method is recommended for quality control, acceptance testing; or it may help to develop or qualify a thermal spray operator's equipment and procedure or to aid in developing thermal spray coatings with improved adhesion and integrity.3.2 This test method is useful for comparing adhesion or cohesion strengths of coatings of similar types of thermal spray materials. The test should not be considered to provide an intrinsic value for direct use in making calculations, such as to determine if a coating will withstand specific environmental stresses. Because of residual stresses in thermal spray coatings, actual strength depends upon the shape of the particular coated part. Also, in use, a coating may be stressed in a more complex manner than is practical for a standard test.1.1 This test method covers the determination of the degree of adhesion (bonding strength) of a coating to a substrate or the cohesion strength of the coating in a tension normal to the surface. The test consists of coating one face of a substrate fixture, bonding this coating to the face of a loading fixture, and subjecting this assembly of coating and fixtures to a tensile load normal to the plane of the coating. It is adapted particularly for testing coatings applied by thermal spray, which is defined to include the combustion flame, plasma arc, two-wire arc, high-velocity oxygen fuel, and detonation processes for spraying feedstock, which may be in the form of, wire, rod, or powder.NOTE 1: Thermal spray coating materials include ceramics, such as metal oxides or carbides, and metals. In some cases, a coating is formed of different spray materials, such as an oxide layer sprayed onto a sprayed metal-bonding layer. The substrate generally is a metal, but may be a ceramic, such as an oxide or graphite.1.2 Usually this test method is performed at ambient temperature. Higher temperature testing is restricted by the need for a suitable adhesive bonding agent. For certain fundamental investigations, it is suggested that very low (cryogenic) temperature be used.1.3 This test method is limited to testing thermal spray coatings that can be applied in thickness greater than 0.015 in. (0.38 mm). The limitation is imposed because an adhesive bonding agent is used in the test. Those bonding agents established so far for this method tend to penetrate thermal spray coatings and may invalidate results unless the coatings are thick enough to prevent penetration through the coating. Further development may establish that thin layers of certain types of especially dense coatings may be tested satisfactorily. Alternatively, new adhesive bonding agents that would allow reduction of the minimum thickness limitation may become available.1.4 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.1.5 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

5.1 A major factor affecting the life of insulating materials is thermal degradation. It is possible that other factors, such as moisture and vibration, will cause failures after the material has been weakened by thermal degradation.5.2 Electrical insulation is effective in electrical equipment only as long as it retains its physical and electrical integrity. The following are potential indicators of thermal degradation: weight change, porosity, crazing, and generally a reduction in flexibility. Thermal degradation is usually accompanied by an ultimate reduction in dielectric breakdown.5.3 This test method is useful in determining the thermal endurance of coating powders applied over a steel substrate material.1.1 This test method provides a procedure for evaluating thermal endurance of coating powders by determining the length of aging time at selected elevated temperatures required to achieve dielectric breakdown at room temperature at a pre-determined proof voltage. Thermal endurance is expressed in terms of a temperature index.1.2 This test method is applicable to insulating powders used over a substrate material of steel.1.3 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 are not necessarily exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems is likely to result in non-conformance with the standard.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. Specific precautionary statements are given in Section 7.1.5 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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏
263 条记录,每页 15 条,当前第 1 / 18 页 第一页 | 上一页 | 下一页 | 最末页  |     转到第   页