定价： 260元 / 折扣价： 221 元 加购物车

定价： 689元 / 折扣价： 586 元 加购物车

定价： 481元 / 折扣价： 409 元 加购物车

定价： 481元 / 折扣价： 409 元 加购物车

定价： 260元 / 折扣价： 221 元

定价： 0元 / 折扣价： 0 元 加购物车

定价： 689元 / 折扣价： 586 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

This practice is intended for guidance and instruction of the aircraft and unmanned aircraft systems industries when addressing the requirements of Part 21.1.1 In this practice, certification procedures are provided for Unmanned Aircraft Systems (UAS) in the Light UAS Class and in the Remotely Operated Aircraft (ROA) UAS Classes. Unmanned Aircraft Systems in the Mini UAS and Micro UAS Classes are not considered in this practice, since they do not undergo airworthiness certification.1.2 Citations of Federal Aviation RegulationsWhen citing U.S. Federal Aviation Regulations in this practice, the citation references are based on the following Federal Aviation Regulation structure:1.2.1 The Code of Federal Regulations, Title 14 (14 CFR) comprises Aeronautics and Space Regulations. Chapter 1 of 14 CFR contains the regulations of the Federal Aviation Administration and is subdivided into subchapters and parts:The Parts are further subdivided into Subparts and sections.1.2.2 This practice uses Part 21 as a template. Within the text of the practice:14 CFR Chapter 1 means the whole of Chapter 1 of 14 CFR; andSubchapter C means all of the Parts of Subchapter C of 14 CFR.1.2.3 In compact notation, citation of section 1309 of Part 23, for example, may be designated as "section 23.1309."1.3 Unmanned Aircraft SystemsAn Unmanned Aircraft System (UAS) comprises an unmanned air vehicle, the remote control ground station that provides for the mission management and piloting of the air vehicle, data-links for the exchange of control and sensor payload data and all related interfaces. Any part of the overall system that could affect the airworthiness and safety of the aircraft is subject to the requirements of Part 21.1.4 &inch-pound-units;1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety 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 the standard for iron-chromium-nickel, high-alloy tubes made by the centrifugal casting process intended for use under pressure at high temperatures. The tubing shall be supplied in the as cast condition or as cast with machining on the outside or inside surfaces. The material shall conform to the required chemical composition in carbon, manganese, silicon, chromium, nickel, phosphorus, sulfur, and molybdenum. Tension test shall be performed in the tubing at elevated temperature and shall conform to the required values in tensile strength and elongation. Tubing shall meet several tests such as; pressure test, flattening test, and mechanical test.1.1 This specification covers iron-chromium-nickel, high-alloy tubes made by the centrifugal casting process intended for use under pressure at high temperatures.1.2 The grades of high alloys detailed in Table 1 are intended for applications requiring strength and resistance to corrosion and scaling at high temperatures.1.3 Optional Supplementary Requirements S1 to S11 are provided; these call for additional tests to be made if desired.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.4.1 Within the text, the SI units are shown in brackets.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 元 加购物车

This specification covers carbon steel castings for general applications. The grades of steels covered here are: Grade N-1, Grade N-2, Grade U-60-30 [415-205], Grade 60-30 [415-205], Grade 65-35 [450-240], Grade 70-36 [485-250] and Grade 70-40 [485-275]. Except for Grades N-1 and U-60-30, all steel castings shall be heat-treated by full annealing, normalizing, normalizing and tempering, or quenching and tempering. Heat treatments shall be performed after castings have been allowed to cool. Heat and product analyses shall be performed wherein specimens shall conform to required chemical composition of carbon, manganese, silicon, sulfur and phosphorus. Except for Grades N-1 and N-2, all steels shall undergo tension test, and shall conform to the following mechanical requirements: tensile strength, yield point, elongation, and reduction of area.1.1 This specification covers carbon steel castings for general applications that require up to 70 ksi (485 MPa) minimum tensile strength.NOTE 1: The grades covered by this specification represent materials that are suitable for assembly with other steel castings or wrought steel parts by fusion welding. It is not intended to imply that all these grades possess the same degree of weldability or that the same welding techniques can be used on all castings. It is the responsibility of the purchaser to establish for himself a suitable welding technique.1.2 Several grades and two classes of steel castings are covered, as indicated below. The grade and class desired shall be specified by the purchaser.1.2.1 Grade N-1—Chemical analysis only.1.2.2 Grade N-2—Heat treated but not mechanically tested.1.2.3 Grade U-60-30 [415-205]—Mechanically tested but not heat treated.1.2.4 Grades 60-30  [415-205], 65-35 [450-240], 70-36 [485-250], and 70-40 [485-275]—Heat treated and mechanically tested.1.2.5 Class 1 and Class 2 steel castings shall be specified in accordance with 9.2.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.4 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 元 加购物车

5.1 Polyethylene piping has been used instead of steel alloys in the petrochemical, power, water, gas distribution, and mining industries due to its resistance to corrosion and erosion and reliability. Recently, polyethylene pipe has also been used for nuclear safety related cooling water applications.5.2 MW examination is useful for detecting various flaws that are known to occur in polyethylene electrofused joints.1.1 This practice covers microwave (MW) examination of electrofusion joints made entirely of polyethylene for the purpose of joining polyethylene piping.NOTE 1: The notes in this practice are for information only and shall not be considered part of this practice.NOTE 2: This practice references HDPE and MDPE for pipe applications as defined by Specification D3350.1.2 The electrofusion joining process can be subject to a variety of flaws including, but not limited to, lack of fusion, particulate contamination, inclusions, and voids.1.3 The practice is intended to be used on joint thicknesses of 0.5 in. to 4 in. (12 mm to 100 mm) and diameters 4 in. (100 mm) and greater. Greater and lesser thicknesses and lesser diameters may be tested using this standard practice if the technique can be demonstrated to provide adequate detection on mockups of the same wall thickness and geometry.1.4 This practice can be applied to post assembly inspection of polyethylene electrofusion joints.1.5 This practice does not specify acceptance criteria.1.6 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.1.7 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 元 加购物车

This specification covers the design, manufacturing, and testing of packed slip-type expansion joints used in pipelines for accommodating axial thermal growth or contraction from the pipeline carrying fluid. The expansion joints shall be of the following types, styles, classes, and forms: Type I; Styles I and II; Classes I and II; and Forms I, II, and III. As specified in this specification and as required, the expansion joint shall be provided with flanged or welded end connections, limit stops, stuffing boxes with integral guides, base, drain connection, service connection, slip protectors, and adjustment rods. The internal and external surfaces of the expansion joint shall be cleaned of dirt, oil, grease, and other foreign material using a suitable cleaning solvent. Extreme care shall be used to ensure the interior is free of any slag, steel chips, or other similar materials that could lodge between the slip and the body and score the slip surface.1.1 This specification covers the design, manufacturing, and testing of packed slip-type expansion joints used in pipelines for accommodating axial thermal growth or contraction from the pipeline carrying fluid.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 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 Asphalt-based, solvent-type, fibered or nonfibered, aluminum-pigmented roof coatings are used as a protective coating for solar reflection to prolong the life of roofing materials or where decorative qualities are desired.3.2 Suitable application of aluminum-pigmented asphalt roof coatings is an important factor in achieving a successful long-term coating. Suitable application is, in part, dependent upon appropriate specifications to guide the work. This guide can be useful in facilitating development of an appropriate specification for surface preparation and application of the roof coating.3.3 Designers/specifiers of coatings may use this guide in preparing the application portion of their specification. Contractors working directly for the building owner may also use this guide.3.4 This guide is not all-inclusive. Manufacturer's application instructions should be consulted and geographical “area practices” considered. Consult membrane manufacturer and coating manufacturer for acceptability of procedures and products.1.1 This guide covers the application methods for Specification D2824/D2824M Aluminum-Pigmented Asphalt Roof Coatings, Nonfibered, and Fibered without Asbestos, for application on asphalt built-up roof membranes, modified bitumen roof membranes, bituminous base flashings, concrete surfaces, metal surfaces, emulsion coatings, and solvent-based coatings. This guide does not apply to the selection of a specific aluminum-pigmented asphalt roof coating type for use on specific projects. The fibered version of these coatings excludes the use of asbestos fibers.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 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 4.1.4 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

1.1 The purpose of this terminology standard is to establish uniformity in terms used in the field of agricultural chemical application. Terms are adopted from related fields and where applicable from Terminology E609.1.2 The terms are appropriate to any agricultural chemical application. Units in parenthesis following a definition are meant as typical and are not exhaustive of all units available for the term.1.3 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