定价： 345元 / 折扣价： 294 元

定价： 345元 / 折扣价： 294 元

定价： 481元 / 折扣价： 409 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

定价： 260元 / 折扣价： 221 元

定价： 481元 / 折扣价： 409 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

4.1 This practice shall be used to provide a representative sample of the material for the purpose of testing various properties. The procedures used in sampling shall include the use of every precaution that will assist in obtaining samples that are truly representative of the nature and condition of the CLSM.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/ and the like. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors. Practice D3740 provides a means of evaluating some of these factors.1.1 This practice explains the procedure for obtaining a representative sample of freshly mixed controlled low-strength material (CLSM) as delivered to the project site on which tests are to be performed to determine compliance with quality requirements of the specifications under which the CLSM is furnished (Note 1). This practice includes sampling from revolving-drum truck mixers and from agitating equipment used to transport central-mixed CLSM. This Practice is based on Practice C172 for concrete.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: Composite samples are required by this practice unless specifically excepted by procedures governing the tests to be performed, such as tests to determine uniformity of consistency and mixer efficiency. Procedures used to select the specific test batches are not described in this practice. It is recommended that random sampling be used to determine overall specification compliance.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. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.2)1.4 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgement. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a projects many unique aspects. The word “standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers hot-mixed, hot-laid asphalt, tar, emulsified asphalt, and recycled bituminous paving mixtures for base, binder, leveling, and surface courses. The aggregates, mineral fillers, bitumen (asphalt cement, tar cement, or emulsified asphalt as appropriate), and bituminous paving mixtures shall be in accordance to specified consistency and compositions. Products shall be sampled, and undergo sieve analysis and other forms of test methods as appropriate for extracting bitumen content, specific gravity, plasticity index, percentage of coated particles, recovery of extracted asphalt, penetration of recovery asphalt, air voids, and absolute viscosity.1.1 This specification covers hot-mixed, hot-laid asphalt, tar, emulsified asphalt, and recycled bituminous paving mixtures for base, binder, leveling, and surface courses.1.2 The values stated in SI units are to be regarded as the standard. Combining values from the two systems may result in nonconformance 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 and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

This specification covers natural or manufactured aggregate for use in job-mixed base and finish-coat full thickness Portland cement, Portland cement-lime and modified Portland cement plasters. Aggregate subjected to five cycles of the soundness test shall show a loss, when weighed in accordance with the grading of a sampling complying with the limitations set forth. The fineness modulus, friable particles, light constituents, organic impurities, material soundness, and sieve analysis of the aggregate shall be tested to meet the requirements prescribed.1.1 This specification covers natural or manufactured aggregate for use in job-mixed base and finish-coat full thickness portland cement-based plasters.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 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the specification.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 元 加购物车

3.1 These test methods are mainly intended for referee purposes but may be used for quality control of rubber production. They may also be used in research and development work and for comparison of different samples in a standard test formula.3.2 These test methods may also be used to obtain values for customer acceptance of rubber.1.1 These test methods specify the standard materials, test formula, mixing procedures, and test methods for the evaluation of acrylonitrile-butadiene rubber (NBR) mixed with carbon black.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： 590元 / 折扣价： 502 元 加购物车

4.1 Preservation of a conducting surface on electrical contact is vital to the continued functioning of such contacts. Contamination of the surface with insulating layers formed by corrosion processes is one potential hazard. Laboratory testing of contacts in MFG tests is used to assess the effectiveness of design features and materials.4.2 MFG tests are used in development studies of processes and materials for contacts. For example, coupon specimens may be exposed to MFG tests to evaluate new contact materials, layers of new coating materials on a supporting substrate, reduced coating thicknesses, or protective surface treatments.4.3 MFG tests are also employed to test the durability of a finished product with respect to atmospheric corrosion. For example, finished connectors may be exposed to a MFG test and their performances compared against each other or against a set of fixed requirements. Relays or switch contacts may be exposed in the operated and non-operated conditions to compare performance.4.4 MFG tests are useful for determining the effectiveness of connector housings and shrouds as barriers to ingress of atmospheric corrodants to the contact surfaces. These tests can also be used to assess the screening of the metal-to-metal contact areas of mated connectors.4.5 MFG tests are employed as qualification tests to determine connector failure rates in application environments for which correlation between test and application has previously been established.4.6 This guide provides test conditions which are to be applied in conjunction with Practice B827 which defines the required test operation and certification procedures, tolerances, and reporting requirements. Where the test specifier requires certifications or tolerances different than those provided in Practice B827, the required certifications or tolerances shall be part of the test specification. Differences from the specifications in Practice B827 shall be reported in the test report provided by the test operator to the test specifier. Specification of one of the test conditions defined in this document in the form of a statement such as, “Parts shall be tested in accordance with ASTM B845 Method Z,” implicitly requires test condition, Z, applied according to Practice B827.1.1 The techniques described in this guide pertain to mixed flowing gas (MFG) tests containing species that are applied to evaluate devices containing electrical contacts such as slip rings, separable connectors, electromechanical relays or switch contacts. These techniques may be relevant to other devices, but it is the responsibility of the user to determine suitability prior to testing.1.2 The MFG tests described in this guide are designed to accelerate corrosive degradation processes. These accelerations are designed such that the degradation occurs in a much shorter time period than that expected for such processes in the intended application environment of the device being tested. Application environments can vary continuously from benign to aggressively corrosive. Connectors and contacts within closed electronic cabinets may be affected by an environment of different severity than the environment on the outside of such cabinets. In general, indoor environments are different than outdoor environments. The MFG tests described herein, being discrete embodiments of specific corrosive conditions, cannot be representative of all possible application environments. It is the responsibility of the test specifier to assure the pertinence of a given test condition to the specifier's application condition.1.3 The MFG tests described herein are not designed to duplicate the actual intended application environment of the device under test. An extended bibliography that provides information which is useful to test specifiers to assist them in selecting appropriate test methods is included in this guide. The bibliography covers the scope from application condition characterization, single and multiple gas effects, and material and product effects to key application and test variables as well as discussions of atmospheric corrosion processes.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 become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, 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： 646元 / 折扣价： 550 元 加购物车