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ASTM A49-2019 pdf free download

ASTM A49-2019 pdf free download.Standard Specification for Heat-Treated Carbon Steel Joint Bars, Microalloyed Joint Bars, and Forged Carbon Steel Compromise Joint Bars
1. Scope
1.1 This specification covers heat-treated carbon steel joint bars, microalloyed joint bars, and forged compromise joint bars for general use in standard railroad track. 1.2 The joint bars may be used for the production of insulated joints. 1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Ordering Information
3.1 Orders for joint bars under this specification shall include the following information as appropriate: 3.1.1 Quantity—number of pairs of bars, 3.1.2 Type—design or type bar along with section designa- tion and weight of rails being joined, 3.1.3 Dimension—overall length, 3.1.4 Punching—type (elliptical, oval, round, or combinations), size, number, location, spacing and elevation of punched holes, with dimensional drawing if necessary, 3.1.5 Head Easement—if required, and 3.1.6 Certification and Test Report Requirements (see 12.1).
4. Manufacture
4.1 The steel shall be made by one or both of the following processes: basic-oxygen or electric-furnace. 4.1.1 The steel may be cast by a continuous process, or in ingots. 4.2 Heating and Quenching—Quenched carbon-steel joint bars and forged compromise joint bars shall be uniformly heated for punching, slotting, shaping, and forging and subse- quently quenched. Maximum depth of decarburized layer of forged bars shall not exceed 0.040 in. 4.3 Microalloyed joint bars shall be produced from hot rolled steel sections. Bars shall be sheared or sawed cold, and holes shall be drilled. No reheating and quenching is required.
5. Chemical Requirements
5.1 The chemical composition of the quenched carbon-steel joint bars and forged compromise joint bars determined as prescribed in 5.3 shall be within the limits shown in Table 1. 5.2 The chemical composition ofthe microalloyed joint bars shall be agreed upon by the purchaser and the manufacturer. Microalloying shall be accomplished with columbium, vanadium, and nitrogen, or combinations thereof. 5.3 Heat or Cast Analysis—Separate analysis shall be made from test samples representing one of the first three and one of the last three ingots or continuously cast blooms preferably taken during the pouring of the heat. Determinations may be made chemically or spectrographically. Any portion ofthe heat meeting the chemical analysis requirements of Table 1 may be applied. The first heat analysis shall be recorded as the official heat analysis, but the purchaser shall have access to all ladle analyses. Additionally, any material meeting the product analy- sis limits shown in Table 2 may be applied after testing such material in accordance with Specification A29/A29M. 5.4 Product Analysis—When ladle tests are not available, finished material representing the heat may be product tested. The product analysis allowance beyond the limits of the specified ladle analysis shall be within the limits for product analyses specified in Table 2. 5.4.1 An analysis may be made by the purchaser from a sample taken from a finished joint bar representing each heat or cast. The chemical composition thus determined shall conform to the requirements in Table 2.
6. Tensile Requirements
6.1 Properties: 6.1.1 The material as represented by a tension test specimen shall conform to the tensile properties prescribed in Table 3. 6.1.2 The yield point prescribed in Table 3 may be deter- mined by the drop ofthe beam or halt ofthe gage ofthe testing machine, or by use of dividers. Where a definite yield point is not exhibited, the yield strength method defined in 6.1.3 shall be used. 6.1.3 The yield strength prescribed in Table 3 shall be determined by a strain gage or extensometer reading to 0.0002 in. (0.005 mm). Yield strength may be defined as the stress at 0.5 % total strain under load or as the stress at 0.2 % offset. The method described in Test Methods and Definitions A370 shall be followed. After the yield point has been passed, the extensometer may then be removed and the test continued to determine the tensile strength.

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