Q/BQB 302-2023 English PDF (QBQB302-2020, QBQB302-2018)

Q/BQB 302-2023 BQB ENTERPRISE STANDARD OF BAOSHAN IRON AND STEEL CO., LTD. Replacing Q/BQB 302-2020 Continuously Hot-Rolled Steel Sheet and Strip for Cold Forming ISSUED ON: APRIL 9, 2023 IMPLEMENTED ON: JULY 1, 2023 Issued by: Baoshan Iron and Steel Co., Ltd. Table of Contents Foreword ... 3 1 Scope ... 4 2 Normative References ... 4 3 Terms and Definitions ... 5 4 Classification and Code ... 5 5 Information Required for Ordering ... 6 6 Size, Shape, Weight and Tolerance ... 6 7 Technical Requirements ... 7 8 Inspection and Test ... 10 9 Packaging, Marking and Inspection Documents ... 12 10 Numerical Rounding Rules ... 12 11 Appendix... 12 Appendix A (Informative) References of Mechanical Properties ... 13 Appendix B (Informative) Comparison Table between this Document and Similar Designations in Relevant Standards ... 14 Continuously Hot-Rolled Steel Sheet and Strip for Cold Forming 1 Scope This Document specifies the size, shape, technical requirements, inspection and testing, packaging, marking and inspection documents of continuously hot-rolled steel sheet and strip for cold forming. This Document applies to the hot-rolled steel strip for cold forming produced by Baoshan Iron and Steel Co., Ltd., as well as the steel sheet cut horizontally and the steel strip cut longitudinally, hereinafter referred to as steel sheet and strip. 2 Normative References The provisions in following documents become the essential provisions of this Document through reference in this Document. For the dated documents, only the versions with the dates indicated are applicable to this Document; for the undated documents, only the latest version (including all the amendments) is applicable to this Document. GB/T 222-2006 Permissible Tolerances for Chemical Composition of Steel Products GB/T 223 Chemical Analysis Method of Iron, Steel and Alloy (Applicable Parts) GB/T 228.1-2021 Metallic materials - Tensile testing - Part 1: Method of test at room temperature GB/T 232 Metallic materials – Bend test GB/T 2975 Steel and steel products – Location and preparation of samples and 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 8170 Rules of rounding off for numerical values and expression and judgment of limiting values GB/T 20066 Steel and Iron - Sampling and Preparation of Samples for the Determination of Chemical Composition GB/T 20123 Steel and iron - Determination of total carbon and sulfur content - Infrared 5 Information Required for Ordering 5.1 Users need to provide the following information when ordering: a) This Document number; b) Product category; c) Designation, surface treatment method and surface quality level; d) Specifications and dimensional accuracy (thickness, width, unevenness); e) Edge state; f) Usage; g) Type of verification file. 5.2 Omissions in the ordering contract 5.2.1 If the surface treatment method is not specified, except for designations BRC1, BRC2 and BRC3, which are delivered by pickled surfaces, other designations are delivered by rolled surfaces. 5.2.2 For hot-rolled steel sheets and strips, if the dimensional accuracy is not specified, they will be delivered with ordinary accuracy; if the edge condition is not specified, the steel strips will be delivered in an untrimmed state, and the steel plates will be delivered in a trimmed state. 5.2.3 For hot-rolled pickled steel sheets and strips, if the dimensional accuracy is not specified, the thickness shall be delivered with higher thickness accuracy and other dimensions shall be delivered with ordinary accuracy. If the edge condition, surface quality level and whether it is oiled or not is not specified, it shall be delivered by trimmed state, higher level surface and oiled state. If the inner diameter of the steel coil is not specified, it shall be delivered with the inner diameter of the steel coil 610mm. 6 Size, Shape, Weight and Tolerance The size, shape, weight and tolerance of steel sheet and strips shall comply with the provisions of Q/BQB 301. The tolerance of thickness shall comply with the provisions of Table 2 in Q/BQB 301. The allowable value of unevenness shall not exceed the specified minimum yield strength of 300MPa. If the customer has higher requirements for thickness accuracy, the advanced precision PT.C with a specified yield strength less than 360MPa given in Table 4 of Q/BQB 301 can be selected when ordering. transportation, loading and unloading and storage conditions, the supplier shall ensure that the surfaces of the steel sheets and strips shall not rust within 3 months since the completion date of manufacturing. After negotiation between the supplier and the purchaser, and indicating in the contract, the hot-rolled pickled surface can also be supplied without oiling. NOTE: For non-oiled products required by the purchaser, rust may occur; and the surface may be slightly scratched during transportation, loading, unloading, storage and use processes. 7.5 Mechanical and process properties 7.5.1 The performance guarantee period of steel sheets and strips shall comply with the provisions of the corresponding Tables 3, 4 and 5. The performance guarantee period of steel sheets and strips is calculated from the date of completion of product manufacturing. NOTE: Due to the aging nature of steel, it is recommended that users use it as soon as possible. 7.5.2 The mechanical and process properties of steel sheets and strips during the performance guarantee period shall comply with the provisions of the corresponding Tables 3, 4 and 5. When used as raw material for cold rolling, the supplier does not need to conduct the test if the supplier can ensure that the mechanical test is qualified. 7.5.3 After the bend test, there shall be no visible cracks on the outer surface of the specimen. If the supplier can ensure that the bend test is qualified, the test may not be performed. 7.5.4 The mechanical properties of steel sheets and strips with designations of IF HR1, IF HR2 and IF HR3 are referenced in the informative Appendix A, but they are not regarded as guaranteed conditions. 8.6 Reinspection 8.6.1 If a certain test result does not meet the standard requirements, double the number of specimens will be taken from the same batch for reinspecting of the unqualified item. 8.6.2 If the reinspection results (including all indicators required for the test of the project) are qualified, the entire batch will be qualified. If even one index of the reinspection results (including all indicators required for the test of the project) fails, the reinspection shall be unqualified. 8.6.3 If the reinspection is unqualified, the individual pieces that have been tested and have unsatisfactory test results cannot be accepted, but the single pieces of the batch of materials that have not been tested can be resubmitted for testing and acceptance one by one. 9 Packaging, Marking and Inspection Documents The packaging, marking and inspection documents of steel sheets and strips shall comply with the provisions of Q/BQB 300. 10 Numerical Rounding Rules The numerical judgment adopts the rounding and comparison method, and the numerical rounding shall comply with the provisions of GB/T 8170. 11 Appendix The comparison table between this Document and similar designations in relevant standards is shown in Appendix B (informative). ......

Q/BQB 302-2020 BQB ENTERPRISE STANDARD OF BAOSHAN IRON AND STEEL CO., LTD. Continuously Hot Rolled Steel Plates and Strips for Cold Forming Issued on: April 27, 2020 Issued by: Baoshan Iron and Steel Co., Ltd. Self-commitment The content of Q/BQB 302-2020 "Continuously Hot Rolled Steel Plates and Strips for Cold Forming" compiled and published by our company meets the requirements of relevant national laws and regulations, mandatory standards and related industrial policies. It is approved and issued by the corporate representative in accordance with prescribed procedures. The products produced by our company meet the technical requirements specified in this Standard. The standard number is clearly indicated on the corresponding product or product packaging. Our company is responsible for the authenticity, accuracy and legality of the declared information, and assumes full legal responsibility for the consequences of the implementation of this Standard. Baoshan Iron and Steel Co., Ltd. April 27, 2020 Indicator requirement document for technical indicators 1 Main technical indicators and test methods (public declaration) 1 Chemical composition Table 2 2 Mechanical and technological properties Designation Chemical composition a,b (mass fraction) / % a It is selected by the supplier. Special elements can be added. b The contents of residual elements in the steel are: Cu≤0.20%, Cr≤0.15%, Ni≤0.15%. But when the supplier can guarantee, chemical analysis of these elements may not be performed. c When the thickness t>14mm, the upper limit of Mn content can be increased to 0.50%. ......

Q/BQB 302-2018 ENTERPRISE STANDARD OF BAOSTEEL Continuously Hot-Rolled Steel Sheet and Strip for Cold Forming Issued on: February 07, 2018 Issued by: Baoshan Iron & Steel Co., Ltd. Table of Contents Self-Commitment ... 3 Technical Indicator 1 ... 4 Document for Indicator Requirements of Technical Indicator 1 ... 5 Self-Commitment The contents specified in Q/BQB 302-2018 Continuously Hot-Rolled Steel Sheet and Strip for Cold Forming, which is prepared and published by our company, comply with the requirements of relevant national laws and regulations, mandatory standards, and relevant industrial policies; are approved to be published by the legal representative of the enterprise in accordance with the prescribed procedures. The products produced by our company meet the technical requirements stipulated in this Standard; the standard number is clearly indicated on the package of corresponding product. Our company is responsible for the truthfulness, accuracy and legality of the public information in the self-commitment; assumes full legal responsibility for the consequences of the implementation of this Standard. Baoshan Iron & Steel Co., Ltd. February 07, 2018 Document for Indicator Requirements of Technical Indicator 1 1 Size, Shape, Weight and Permissible Deviation The size, shape, weight and permissible deviation of steel sheet and strip shall conform to the provisions of Q/BQB 301; thereof, the permissible deviation of thickness shall conform to the provisions of Table 2 in Q/BQB 301; the allowable value of unevenness shall not conform to the provisions of the minimum yield strength no greater than 300MPa. If the purchaser has higher requirements for the thickness accuracy, the advanced accuracy PT.C with specified yield strength, Re, less than 360MPa given in Table 4 of Q/BQB 301. 2 Technical Requirements Table 2 Designation Chemical composition a, b (mass fraction) / % a it shall be selected by the supplier, and the special elements may be added. b Content of residual elements in steel, such as Cu≤0.20%, Cr≤0.15%, Ni≤0.15%. However, under the guarantee of the supplier, the chemical analysis on these elements may not be conducted. c When thickness t>14mm, the upper limit for content of Mn may be improved to 0.50%. ......