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

4.1 This test method indicates approximate change in properties of asphalt during conventional hot-mixing at about 302 °F (150 °C) as indicated by viscosity and other rheological measurements. It yields a residue which approximates the asphalt condition as incorporated in the pavement. If the mixing temperature differs appreciably from the 302 °F (150 °C) level, more or less effect on properties will occur. This test method can also be used to determine mass change, which is a measure of asphalt volatility.NOTE 1: The quality of results produced by this standard is dependent on the competence of the personnel performing the procedure and the capability, 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 guidance provides a means of evaluating and controlling some of those factors.1.1 This test method is intended to measure the effect of heat and air on a moving film of semi-solid asphaltic materials. The effects of this treatment are determined from measurements of the selected properties of the asphalt before and after the test.1.2 The values stated in inch-pound units are to be regarded as the standard.1.3 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.1.4 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: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

5.1 This guide is intended as a guideline for fluid analysis programs and serves as an initial justification for selecting fluid tests and sampling frequencies. Plant operating experience along with the review and benchmarking of similar applications is required to ensure that lessons learned are implemented.5.2 Selection of proper fluid tests for assessing in-service component condition may have both safety and economic implications. Some failure modes may cause component disintegration, increasing the safety hazard. Thus, any fluid test that can predict such conditions should be included in the condition-monitoring program. Conversely, to maintain a sustainable and successful fluid-monitoring program, the scope of the fluid tests and their frequency should be carefully balanced between the associated risks versus expected program cost savings and benefits.5.3 The failure modes monitored may be similar from one application to the next, but the risk and consequences of failure may differ.5.4 This analysis can be used to determine which in-service lubricant analysis tests would be of highest value and which would be ineffective for the failure modes of interest. This information can also be used to determine the best monitoring strategy for a suite of failure modes and how often assessment is needed to manage the risk of failure.1.1 This guide describes a methodology to select tests to be used for in-service lubricant analysis. The selection of fluid tests for monitoring failure mode progression in industrial applications applies the principles of failure mode and effect analysis (FMEA).1.2 Although typical FMEA addresses all possible product failure modes, the focus of this guide is not intended to address failures that have a very high probability of unsafe operation as these should immediately be addressed by other means.1.3 This guide is limited to components selected for condition-monitoring programs by providing a methodology to choose fluid tests associated with specific failure modes for the purpose of identifying their earliest developing stage and monitoring fault progression. The scope of this guide is also focused on those failure modes and their consequences that can effectively be detected and monitored by fluid analysis techniques.1.4 This guide pertains to a process to be used to ensure an appropriate amount of condition monitoring is performed with the objective of improving equipment reliability, reducing maintenance costs, and enhancing fluid analysis monitoring of industrial machinery. This guide can also be used to select the monitoring frequencies needed to make the failure determinations and provide an assessment of the strengths and weaknesses of a current condition-monitoring program.1.5 This guide does not eliminate the programmatic requirements for appropriate assembly, operational, and maintenance practices.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 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

4.1 This guide is intended for use by those undertaking the development of fire hazard assessments for upholstered seating furniture in health care occupancies.4.2 As a guide this document provides information on an approach to development of a fire hazard assessment, but fixed procedures are not established. Section 1.7 describes some cautions to be taken into account.4.3 A fire hazard assessment developed following this guide should specify all steps required to determine fire hazard measures for which safety thresholds or pass/fail criteria can be meaningfully set by responsible officials using the standard.4.4 A fire hazard assessment developed as a result of using this guide should be able to assess a new item of upholstered seating furniture being considered for use in a certain health care facility, and reach one of the conclusions in 4.4.1 – 4.4.4.4.4.1 The new upholstered seating furniture item is safer, in terms of predicted fire performance, than the one in established use. Then, the new product would be desirable, from the point of view of fire safety.4.4.2 There is no difference between the predicted fire safety of the new item and the one in established use. Then, there would be neither advantage nor disadvantage in using the new product, from the point of view of fire safety.4.4.3 The new upholstered seating furniture item is predicted to be less safe, in terms of fire performance, than the one in established use. Then, the new item would be less desirable, from the point of view of fire safety than the one in established use.4.4.3.1 If the new upholstered furniture item is predicted to be less safe, in terms of fire performance, than the one in established use, a direct substitution of the products would provide a lower level of safety and the new product should not be used, without other compensatory changes being made. A new upholstered furniture product can, however, be made acceptable if, and only if, it is part of a complete, comprehensive, fire safety design for the patient room. Such a patient room redesign should include one or more of the following features: use of an alternative layout (albeit one that cannot be altered by the patient room users) or increased use of automatic fire protection systems or changes in other furnishings or contents. In such cases, a more in-depth fire hazard assessment should be conducted to ensure that all of the changes together have demonstrated a predicted level of fire safety for the new design which is at least equal to that for the design in established use, in order to permit the use of the new upholstered seating furniture item.4.4.3.2 Alternatively, the new design may still be acceptable if the predicted level of fire safety is commensurate with new stated fire safety objectives developed in advance.4.4.4 The new upholstered seating furniture item offers some safety advantages and some safety disadvantages over the item in established use. An example of this outcome could be increased smoke obscuration with decreased heat release. Then, a more in depth fire hazard assessment would have to be conducted to balance the advantages and disadvantages.4.5 If the patient room does not contain an upholstered seating furniture item, then the fire hazard assessment implications of the introduction of an upholstered seating furniture item should be analyzed in the same way as in 4.4. The fire safety should then be compared with that achieved in the room in established use (which has no upholstered seating furniture). The same analysis would also apply if an additional upholstered furniture item is being considered for introduction in a patient room: the fire hazard assessment should compare the fire safety implications of the addition.4.5.1 An additional upholstered furniture item adds to the fuel load of a room. Thus, an analysis such as that in 4.4 would offer options 4.4.2 through 4.4.4 only.4.6 Following the analysis described in 4.4, a fire hazard assessment developed following the procedures in this guide would reach a conclusion regarding the desirability of the furniture product studied.4.7 An alternative to the analysis based on the anticipated fire performance of the materials or products contained in the patient room is the use of active fire protection measures, such as fire suppression sprinklers. Active fire protection involves measures such as automatic sprinklers and alarm systems, while passive fire protection involves using materials that are difficult to burn and give off low heat and smoke if they do burn. Traditional prescriptive requirements are based exclusively on passive fire protection, with the common approach being to describe the fire tests to be met for every property. The opposite extreme is based entirely on active fire protection, which assumes that active fire protection measures (mostly sprinklers) ensure fire safety. The fire safety record of sprinklers is excellent, but not flawless. Moreover, neither approach gives the type of flexibility that is the inherent advantage of fire hazard and fire risk assessments.4.7.1 Note that the activation of automatic fire suppression sprinklers does not ensure a safe level of smoke obscuration.4.8 This guide provides information on a different type of fire hazard assessment than Guide E2061. While Guide E2061 considers an entire occupancy, namely a rail transportation vehicle, this guide addresses a specific product, namely upholstered furniture.1.1 This is a guide to developing fire hazard assessments for upholstered seating furniture, within patient rooms of health care occupancies. As such, it provides methods and contemporary fire safety engineering techniques to develop a fire hazard assessment for use in specifications for upholstered seating furniture in such occupancies.1.2 Hazard assessment is an estimation of the potential severity of the fires that can develop with certain products in defined scenarios, once the incidents have occurred. Hazard assessment does not address the likelihood of a fire occurring, but is based on the premise that an ignition has occurred.1.3 Because it is a guide, this document cannot be used for regulation, nor does it give definitive instructions on how to conduct a fire hazard assessment.1.4 This guide is intended to provide assistance to those interested in mitigating the potential damage from fires associated with upholstered furniture in patient rooms in health care occupancies.1.5 Thus, this guide can be used to help assess the fire hazard of materials, assemblies, or systems intended for use in upholstered furniture, by providing a standard basis for studying the level of fire safety associated with certain design choices. It can also aid those interested in designing features appropriate to health care occupancies. Finally, it may be useful to safety personnel in health care occupancies.1.6 This guide is a focused application of Guide E1546, which offers help in reference to fire scenarios that are specific to upholstered furniture in health care occupancies, and includes an extensive bibliography. It differs from Guide E1546 in that it offers guidance that is specific to the issue of upholstered furniture in patient rooms of health care facilities, rather than general guidance. Appendix X11 includes some statistics on the magnitude of the potential problem in the U.S.1.7 A fire hazard assessment conducted in accordance with this guide is strongly dependent on the limitations in the factors described in 1.7.1 – 1.7.4.1.7.1 Input data (including their precision or accuracy).1.7.2 Appropriate test procedures.1.7.3 Fire models or calculation procedures that are simultaneously relevant, accurate and appropriate.1.7.4 Advancement of scientific knowledge.1.8 This guide addresses specific fire scenarios which begin inside or outside of the patient room. However, the upholstered furniture under consideration is inside the patient room.1.9 The fire scenarios used for this hazard assessment guide are described in 9.2. They involve the upholstered furniture item within the patient room as the first or second item ignited, in terms of the room of fire origin. Additionally, consideration should be given to the effect of the patient room upholstered furniture item on the tenability of occupants of rooms other than the room of fire origin, and on that of potential rescuers.1.10 This guide does not claim to address all fires that can occur in patient rooms in health care occupancies. In particular, fires with more severe initiating conditions than those assumed in the analysis may pose more severe fire hazard than that calculated using this guide (see also 9.5).1.11 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.12 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.1.13 This fire standard cannot be used to provide quantitative measures.1.14 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: 843元 / 折扣价: 717 加购物车

在线阅读 收 藏

4.1 The intent of this test method is to determine properties of direct-applied SFRM that may be used to provide an indication of serviceability. Satisfactory performance of fire-resistive material applied to structural members and assemblies depends upon its ability while in place to withstand the various influences that may occur during the life of the structure, as well as upon its satisfactory performance under fire tests.4.2 This test method measures the behavior of SFRM when subjected to deflection and evaluates such phenomena as spalling and delamination under bending stress. It is an indication of the ability of SFRM to remain in place and resist removal during anticipated service conditions.1.1 This test method covers a procedure for determining the effect of deflection on sprayed fire-resistive material (SFRM) applied to steel deck. These materials include sprayed fibrous and cementitious materials applied directly in contact with the structural members. The test method is applicable only to laboratory procedures.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 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.1.3 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

4.1 The intent of this test method is to determine a property of SFRM that may be used to provide an indication of its in-place serviceability. Satisfactory performance of SFRM applied to structural members and assemblies depends upon its ability to withstand the various influences that may occur during construction and during the life of the structure, as well as upon its satisfactory performance under fire conditions.4.2 The test method measures the behavior of SFRM when the floor construction to which it is applied is subjected to shock loading and evaluates adhesion and resistance to spalling, cracking, and delamination. It is an indication of the ability of SFRM to remain in place and resist removal during anticipated service conditions.1.1 This test method covers a procedure for determining the effect of impact loading on the bonding of sprayed fire-resistive material (SFRM) applied to the underside of steel floor deck. These materials include sprayed fibrous and cementitious materials applied directly in contact with the structural members. The test method is applicable only to laboratory procedures.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 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.1.3 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 Most coatings are designed for a specific baking time and temperature. For a variety of reasons (line stoppages, rerouting back through ovens, oven overheating, etc.) the prescribed time or temperature, or both, of the bake is often exceeded. This practice has been found to be useful in evaluating the effects of overbakes on coatings.1.1 This practice covers the determination of the time-temperature effect of overbaking on the physical and chemical properties of organic coatings.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 whoever uses this standard to consult and establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 7.1.4 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 is of significance in making a final determination of the acceptability of fine aggregates with respect to the requirements of Specification C33/C33M concerning organic impurities.5.2 This test method is applicable to those samples which, when tested in accordance with Test MethodC40/C40M, have produced a supernatant liquid with a color darker than the standard listed in Table 1 of C40/C40M (Organic plate No. 3, Gardner Color Standard No. 14, Circular Disk No. 14 or prepared color solution).5.3 Many specifications provide for the acceptance of fine aggregate producing a darker color in the Test Method C40/C40M test, if testing by this test method indicates the strength of the mortar cubes prepared with the unwashed fine aggregate is comparable to the strength of mortar cubes made with the washed fine aggregate.1.1 This test method covers the determination of the effect on mortar strength of the organic impurities in fine aggregate, whose presence is indicated using Test Method C40/C40M. Comparison is made between compressive strengths of mortar made with washed and unwashed fine aggregate.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. Some values have only SI units because the inch-pound equivalents are not used in the practice.NOTE 1: Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for information only and does not represent a different standard sieve size1.3 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.(Warning—Fresh hydraulic cementitous mixtures are caustic and may cause chemical burns to exposed skin and tissue upon prolonged exposure.)21.4 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 Siliceous alkaline substrates are subject to water damage that may result in deterioration. Water repellents can provide protection of siliceous alkaline substrates exposed to water. This test method is used to evaluate the efficacy of clear water repellents on alkaline substrates.1.1 This test method evaluates the effectiveness of clear water repellents on hydraulic cement mortar specimens based on water absorption after a water soak.1.2 The values stated in SI units are to be regarded as the standard. The values 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
ASTM D794-93 Practice for Determining Permanent Effect of Heat on Plastics (Withdrawn 1998) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

定价: 0元 / 折扣价: 0

在线阅读 收 藏

1.1 This test method covers an accelerated procedure for predicting the effect of weathering on adhesion, surface cracking and peeling, deep bead cracking, oil exudation, and wrinkling of face glazing or bedding compounds, or both, intended for exterior use on steel, aluminum, or other metal sash.1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.1.3 The committee with jurisdiction over this standard is not aware of any equivalent standard published by other ASTM committees, ISO or any other standards organizations.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 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 Surface grinding can cause a significant decrease4 in the flexure strength of advanced ceramic materials. The magnitude of the loss in strength is determined by the grinding conditions and the response of the material. This test method can be used to obtain a detailed characterization of the relationship between grinding conditions and flexure strength for an advanced ceramic material. The effect on flexure strength of varying a single grinding parameter or several grinding parameters can be measured. The method may also be used to compare and rank different materials according to their response to one or more different grinding conditions. Results obtained by this method can be used to develop an optimum grinding process with respect to maximizing material removal rate for a specified flexure strength requirement. The test method can assist in the development of improved grinding-damage-tolerant ceramic materials. It may also be used for quality control purposes to monitor and assure the consistency of a grinding process in the fabrication of parts from advanced ceramic materials. The test method is applicable to grinding methods that generate a planar surface and is not directly applicable to grinding methods that produce non-planar surfaces such as cylindrical and centerless grinding.1.1 This test method covers the determination of the effect of surface grinding on the flexure strength of advanced ceramics. Surface grinding of an advanced ceramic material can introduce microcracks and other changes in the near surface layer, generally referred to as damage (see Fig. 1 and Ref. (1)).2 Such damage can result in a change—most often a decrease—in flexure strength of the material. The degree of change in flexure strength is determined by both the grinding process and the response characteristics of the specific ceramic material. This method compares the flexure strength of an advanced ceramic material after application of a user-specified surface grinding process with the baseline flexure strength of the same material. The baseline flexure strength is obtained after application of a surface grinding process specified in this standard. The baseline flexure strength is expected to approximate closely the inherent strength of the material. The flexure strength is measured by means of ASTM flexure test methods.FIG. 1 Microcracks Associated with Grinding (Ref. (1))21.2 Flexure test methods used to determine the effect of surface grinding are C1161 Test Method for Flexure Strength of Advanced Ceramics at Ambient Temperatures and C1211 Test Method for Flexure Strength of Advanced Ceramics at Elevated Temperatures.1.3 Materials covered in this standard are those advanced ceramics that meet criteria specified in flexure testing standards C1161 and C1211.1.4 The flexure test methods supporting this standard (C1161 and C1211) require test specimens that have a rectangular cross section, flat surfaces, and that are fabricated with specific dimensions and tolerances. Only grinding processes that are capable of generating the specified flat surfaces, that is, planar grinding modes, are suitable for evaluation by this method. Among the applicable machine types are horizontal and vertical spindle reciprocating surface grinders, horizontal and vertical spindle rotary surface grinders, double disk grinders, and tool-and-cutter grinders. Incremental cross-feed, plunge, and creep-feed grinding methods may be used.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 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: 646元 / 折扣价: 550 加购物车

在线阅读 收 藏

4.1 This test method will distinguish between cooling system chemical solutions that do or do not have a tendency to change the surface appearance when applied to organic finishes used on vehicles. Such changes may be manifested by discoloration, loss of gloss, softening, swelling, or other similar phenomena.1.1 This test method determines the effect of cooling system chemical solutions on organic finishes used on motor vehicles. Cooling system chemicals include: coolants or corrosion inhibitors, or both, cooling system cleaners or flushes, or both, and stop leak additives.NOTE 1: This test method is a modification of Method of Test D1540.1.2 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.1.3 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

3.1 Nearly all electronic devices are susceptible to possible damage or degradation from ESD encountered in their operating environments. The sensitivity of the equipment, the potential consequences of a malfunction, and the expected environmental conditions all impact the level of ESD protection needed.3.2 ESD shielding effectiveness test may be destructive, and units that have been tested should be considered unreliable for future use.1.1 This test method is used to determine the electrostatic discharge (ESD) shielding effectiveness of a membrane switch assembly or printed electronic device. This test method may be used to test a membrane switch or printed electronic device to destruction, that is, to determine its maximum ESD shielding effectiveness, or it may be used to test the ability of a membrane switch or printed electronic device to withstand a predetermined level of exposure.1.2 The values stated in SI units are to be regarded as the standard. The values 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 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 Exposing a specimen to conditions of one-directional environmental cycling can increase its moisture content until a decrease in material properties occurs (at a specific number of cycles). Such a test could be inappropriate due to the number of cycles required to cause a decrease in material properties since product performance issues often arise only after many years of exposure. The use of a preconditioning procedure is not intended to duplicate expected field performance. Rather the purpose is to increase the moisture content of test materials prior to subjecting to them to environmental cycling.5.2 The most important aspect of the preconditioning procedure is non-uniform moisture distribution in the specimen. The heat flow is one directional causing moisture flow towards the cold side resulting in zones of dry material on the warm side and high moisture content on the cold side. (Whether the high moisture content zone is located right at the cold surface of the specimen or at some distance from this surface depends upon temperature oscillation and ability of the cold surface to dry outwards). Because the preconditioning procedure involves thermal gradient, this preconditioning procedure results in a distribution of moisture content that may occur under field exposure conditions. However, the resulting moisture content may differ significantly from that which may be demonstrated in typical product applications.5.3 The preconditioning results in accumulation of moisture in the thermal insulation resulting from the simultaneous exposure to a difference in temperature and water vapor pressure. This test method is not intended to duplicate field exposure. It is intended to provide comparative ratings. As excessive accumulation of moisture in a construction system may adversely affect its performance, the designer should consider the potential for moisture accumulation and the possible effects of this moisture on the system performance.1.1 This test method is applicable to preformed or field manufactured thermal insulation products, such as board stock foams, rigid fibrous and composite materials manufactured with or without protective facings. See Note 1. This test method is not applicable to high temperature, reflective or loose fill insulation.NOTE 1: If the product is manufactured with a facer, test product with facer in place.1.2 This test method involves two stages: preconditioning and environmental cycling. During the first stage, 25 mm (1 in.) thick specimens are used to separate two environments. Each of these environments has a constant but different temperature and humidity level. During the environmental cycling stage, specimens also divide two environments namely constant room temperature/humidity on one side and cycling temperature/ambient relative humidity on the other side.1.3 This test method measures the ability of the product to maintain thermal performance and critical physical attributes after being subjected to standardized exposure conditions. A comparison is made between material properties for reference specimens stored in the laboratory for the test period and specimens subjected to the two-stage test method. To eliminate the effect of moisture from the comparison, the material properties of the latter test specimens are determined after they have been dried to constant weight. The average value determined for each of the two sets of specimens is used for comparison.1.4 Different properties can be measured to assess the effect of environmental factors on thermal insulation. This test method requires that thermal resistance be determined based upon an average for three specimens measured after completing the test. Secondary elements of this test method include visual observations such as cracking, delamination or other surface defects, as well as the change in moisture content after each of the two stages of exposure prescribed by the test method.1.5 Characterization of the tested material is an essential element of this test method. Material properties used for characterization will include either compressive resistance or tensile strength values. The compressive resistance or tensile strength is measured on two sets of specimens, one set conditioned as defined in 1.2 and a set of reference test specimens taken from the same material batch and stored in the laboratory for the whole test period. For comparison, an average value is determined for each of the two sets of specimens.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.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

4.1 The test method enables strength values for wood and other materials bonded with an adhesive under a range of controlled bonding temperature, time, and pressure conditions to be evaluated. Bond formation and subsequent testing is affected in a coordinated fashion, and this enables transient strength values of sets of similar bond types to be explored with diverse parameters as independent variables. Principal among these variables is the temperature at which bonds are formed and the time that selected temperatures are maintained prior to testing. The use of controlled methods of adhesive application, the rapid attainment of stable bond formation conditions, and the rapid transition to the bond testing mode enables snapshots of bond strength to be attained as bonds progress from limited strength (or initial tack) to maximum strength. Derived data may be used to evaluate and compare the strength development characteristics of diverse types and formulations of adhesive. The method may thus be used to aid in tailoring and matching adhesives to the manufacture of diverse bonded products that involve heating.4.2 The method may also be used to evaluate the co-dependent effect of temperature and time on the degradation of sample bonds. Pressing temperatures up to 265°C (509°F) may be necessary for such investigations of thermal degradation. Specimens are pressed for a range of times and temperatures and very shortly thereafter tested either at elevated temperature or immediately following rapid forced air cooling. Alternatively, thermal damage of pre-formed bond samples may be evaluated by subjecting them to controlled temperature and time sequences prior to testing.4.3 The method may also be used to evaluate the effect of wood type and variability, or of non-wood materials, on bond strength development.4.4 By hermetically sealing the overlap region of sample bonds during their formation, the method may also be used to evaluate the effect of moisture and other resident volatile fluids on bond strength development.4.5 The method may also be used to evaluate the effect that the temperature at which variously formed bonds are tested has on their strength. Controlled rapid forced air cooling immediately after bond formation but before testing is necessary for such investigations. This approach may be employed to explore the thermoplastic characteristic of thermosetting adhesives and also the strength of hot melt adhesives as a function of pressing and testing temperatures.1.1 This test method concerns bonding and testing of wood adhesives and related adhesives using small scale tensile lap-shear samples in a manner that emphasizes transient cohesive strength as a function of bonding time and temperature.1.2 Use of thin adherends enables bondlines to be rapidly heated to elevated temperatures and maintained at those temperatures for a range of times at a controlled pressure before testing.1.3 Optional rapid forced air cooling of bonds after pressing and immediately before testing enables the effect of testing temperature on transient strength to be evaluated.1.4 Bond overlap distance is specified to ensure that failure occurs in the bondline rather than in unbonded portions of adherend strips, and also to minimize the effect of shear stress non-uniformity along the overlap during tensile testing.1.5 Standard wood or alternative non-standard materials must be of specified high quality and uniformity of structure and dimension to minimize variability of bonding and maximize stress transfer into the bonds during testing.1.6 The effect of wood variability and type, or of the properties of alternative non-wood materials, on bond strength development may be explored using the method.1.7 Optional hermetic sealing of bond overlaps during their heated pressing enables the effect of moisture on bonding to be evaluated.1.8 Thermal damage, either of pre-formed bonds or by prolonging bond forming times, may be evaluated as a function of time and elevated temperature using this test method.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 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. Some specific hazards statements are given in Section 10 on Hazards.1.11 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
42 条记录,每页 15 条,当前第 2 / 3 页 第一页 | 上一页 | 下一页 | 最末页  |     转到第   页