TB/T Translated English of Chinese Standard: TB/T

Transcription

1 Translated English of Chinese Standard: TB/T TB RAILWAY INDUSTRY STANDARD OF THE PEOPLE S REPUBLIC OF CHINA ICS S 05 TB/T Replacing TB/T Atmospheric corrosion resisting steel for railway rolling stock 铁路车辆用耐大气腐蚀钢 Issued on: September 26, 2014 Implemented on: March 1, 2015 Issued by: State Railway Administration Page 1 of 13

2 Table of Contents Foreword Scope Normative references Dimension, shape, weight and allowable deviation Representation method of steel grades Technical requirements Inspection methods Inspection rules Packaging, marking and quality certificate Annex A (informative) Comparison table of atmospheric corrosion resisting steel grades in old- and new- version standards Page 2 of 13

3 Foreword This Standard is drafted according to the rules given in GB/T This Standard replaces TB/T Ordering technical conditions of atmospheric corrosion resisting steel for railway rolling stock ; compared with TB/T , main technical changes are as follows: - ADD the representation method of atmospheric corrosion resisting steel grades (see Clause 4); - The naming of atmospheric corrosion resistant steel grades is changed from the naming by the main chemical composition in steel TO the naming by the lower yield limit of steel (see of this Standard, of 2003 version); - ADD the high-strength atmospheric corrosion resisting steel (see Table 1); - MERGE the cold-rolled 05CuPCrNi steel and cold-rolled 09CuPCrNi-A in the original standard (see Table 1); - ADD the requirements for the control sample Q345B of corrosion resistance test (see Table 6); - MODIFY the batch weight of atmospheric corrosion resisting steel (see 7.2 of this Standard, 6.3 of 2003 version); - ADD the requirements for the corrosion resistance test frequency (see 7.2); - ADD the comparison table of atmospheric corrosion resisting steel grades in newand old-version standards (see Annex A). This Standard is proposed by and under the jurisdiction of Institute of Standards and Metrology of Ministry of Railways. Drafting organizations of this Standard: Institute of Standards and Metrology of Ministry of Railways, Institute of Metals and Chemistry of Institute of Intercalary Railway, Baoshan Iron and Steel Co., Ltd. Main drafters of this Standard: Zhu Mei, Gao Junli, Zhang Bin, Yang Songbai, Qu Zhaoxia. The previous version of the standards replaced by this Standard are as follows: - TB/T , TB/T Page 3 of 13

4 Atmospheric corrosion resisting steel for railway rolling stock 1 Scope This Standard specifies the dimension, shape, weight and allowable deviation, representation method of steel grades, technical requirements, inspection methods, inspection rules, packaging, marking and quality certificates of atmospheric corrosion resisting steel for railway rolling stock. This Standard applies hot-rolled and cold-rolled steel sheet, plate and strip and structural steel of atmospheric corrosion resisting steel for railway rolling stock. 2 Normative references The following documents are indispensable for the application of this document. For dated references, only the dated edition applies to this document. For undated references, the latest edition (including all amendments) applies to this document. GB/T 222 Permissible tolerances for chemical composition of steel products GB/T 223 Methods for chemical analysis of iron, steel and alloy GB/T Metallic materials - Tensile testing - Part 1: Method of test at room temperature GB/T 229 Metallic materials - Charpy pendulum impact test method GB/T 232 Metallic materials - Bend test GB/T 247 General rule of package mark and certification for steel plates (sheets) and strips GB/T 706 Hot rolled section steel GB/T 708 Dimension shape weight and tolerance for cold-rolled steel plates and sheets GB/T 709 Dimension, shape, weight and tolerances for hot-rolled steel plates and sheets Page 4 of 13

5 GB/T 2101 General requirement of acceptance packaging marking and certification for section steel GB/T 2975 Steel and steel products - Location and preparation of test pieces for mechanical testing GB/T 4336 Carbon and low-alloy steel - Determination of multi-element contents - Spark discharge atomic emission spectrometric method (routine method) GB/T 6394 Metal - Methods for estimating the average grain size GB/T Steel - Determination of content of nonmetallic inclusions - Micrographic method using standards diagrams GB/T Steel and steel products - General technical delivery requirements GB/T Steel and iron - Sampling and preparation of samples for the determination of chemical composition GB/T Low-alloy steel - Determination of multi-element contents - Inductively coupled plasma atomic emission spectrometric method TB/T 2375 Test method for cyclic wetting corrosion of weathering steels for railway applications 3 Dimension, shape, weight and allowable deviation 3.1 The dimension, shape, weight and allowable deviation of steel plates, sheets and strips shall comply with the relevant specifications of GB/T 709, GB/T The dimension, shape, weight and allowable deviation of hot-rolled steels shall comply with the relevant specifications of GB/T 706; the dimension, shape, weight and allowable deviation of cold-formed steels shall comply with the corresponding product specifications. 4 Representation method of steel grades The steel grade consists of the lower yield strength code, lower yield strength limit value, atmospheric corrosion resisting steel code, delivery state code and steel category, the specific structure is as follows: Page 5 of 13

6 Q400NQR ~ 3.50 Q450NQR ~ Q450EWR Q500NQR ~ Q550NQR ~ Q265NQL ~ 0.40 Q310NQL ~ 0.75 Q310NQL ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Ti ~ ~ 0.25 ~ ~ NOTE: See Annex A for the comparison of atmospheric corrosion resisting steel grades in newand old-version standards. a RE value is the rare-earth content in the finished steel: when S 0.01%, it can guarantee a certain amount of rare earth residues In order to improve the properties of steels, for Category 1 and Category 2 steels, it may add trace alloying elements such as V, Nb, Ti, however, the sum of these alloys shall not exceed 0.22% The allowable upper deviation between the chemical composition of rare-earth elements in the finished steel and the specified value in Table 1 is 0, and the allowable lower deviation is %. The allowable deviation between other chemical compositions in the finished steel and the specified in Table 1 shall comply with the specifications of GB/T Smelting method The steel is smelted by the oxygen converter or electric furnace, to become the killed steel. 5.3 Delivery state Hot-rolled steels shall be delivered in hot-rolled or hot-rolled annealed condition; cold-rolled steel plates, sheets and strips shall be delivered in annealed flat condition. Through the negotiation between the supply and demand parties, hot-rolled steel plates, sheets and strips can be delivered after being pickled When delivered in flat plate, the four sides of the steel plate shall be neat and at Page 7 of 13

7 NOTE: D in the table is the diameter of the bend, α is the nominal thickness of steel. a When the yield phenomenon is not obvious, use ReL The V-notch impact test results shall comply with the specifications in Table 3. The impact test results are the average of the three test samples, one of which shall be allowed to have a single value lower than the specified value in Table 3, but not lower than 70% of the specified value. When the thickness of steel is less than 6 mm, the impact test is not carried out. When using small dimension (5 mm x 10 mm x 55 mm, 7.5 mm x 10 mm x 55 mm) samples for impact test, the impact absorption energy shall not be less than 50%, 75% of the specified value, respectively. Steel grade Q295NQR2 Q295NQR3 Q345NQR2 Q345NQR3 Q345NQR4 Q350EWRI Q400NQR1 Q450NQR1 Q450EWm Q500NQR1 Q550NQR1 Table 3 Impact properties Thickness Impact absorption energy KV2 (-40 C) mm J Grain size The grain size shall not be less than Grade Nonmetallic inclusions The Category A and Category C inclusions of the coarse and fine series in the steel shall not be more than Grade 2.5, and the Category B, Category D and Category DS inclusions shall not be more than Grade Corrosion resistance The corrosion resistance of steel shall comply with the specifications in Table 4. Page 9 of 13