Q/BQB 301-2019 English PDF (QBQB301-2019)

This Standard specifies the dimension, shape, weight and tolerance of continuously hot-rolled steel sheet and strip. This Standard is applicable to the continuously hot-rolled steel strip produced by Baoshan Iron and Steel Co., Ltd.; as well as the steel sheet horizontally cut from the steel strip and the longitudinally cut steel strip, hereinafter referred to as steel sheet and strip.

Q/BQB 301-2019
ENTERPRISE STANDARD OF
BAOSHAN IRON AND STEEL CO., LTD
Replacing Q/BQB 301-2018
Dimension, Shape, Weight and Tolerances for
Continuously Hot-Rolled Steel Sheet and Strip
ISSUED ON: FEBRUARY 02, 2019
IMPLEMENTED ON: APRIL 10, 2019
Issued by: Baoshan Iron and Steel Co., Ltd.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative References ... 4
3 Classification and Code ... 4
4 Dimension ... 5
5 Dimension Tolerance ... 6
6 Appearance ... 9
7 Measurement of Dimension and Appearance ... 12
8 Weight ... 13
9 Numerical Rounding-Off Rules ... 13
Appendix A (Normative) Weight Calculation Method by Taking Theoretical
Weight ... 15
Foreword
This Standard was drafted as per the rules specified in GB/T 1.1-2009 Directives for Standardization – Part 1: Structure and Drafting of Standards.
This Standard was formulated by reference of GB/T 709-2018, EN 10051:2010 and ISO 16160:2012, and combined with the actual situation of the Baoshan Iron and Steel Co., Ltd.
This Standard replaced Q/BQB 301-2018.
Compared with Q/BQB 301-2018, this Standard has the major changes as follows: --- Extend the maximum width of the steel sheet to 2130mm in Table 1;
--- For the thickness precision, width precision and unevenness precision, add the provisions that the ordinary precision shall prevail to supply the products, when the precisions are not specified in the product standard and contract;
--- Extend the weight of the hot-rolled pickled steel sheet strip to no less than 28000kg in Table 14.
The Appendix A of this Standard is normative.
This Standard was proposed by the Manufacture and Management Department of Baoshan Iron and Steel Co., Ltd.
This Standard shall be under the jurisdiction of the Manufacture and Management Department of Baoshan Iron and Steel Co., Ltd.
Drafting organization of this Standard: Manufacture and Management Department of Baoshan Iron and Steel Co., Ltd.
Drafting staff of this Standard: Huang Jinhua, and Liu Meihong.
The historical editions replaced by this Standard are as follows: Q/BQB 301-1989, Q/BQB 301-1994, Q/BQB 301-1999, Q/BQB 301-2003, Q/BQB 301-2009, Q/BQB 301- 2014, Q/BQB 301-2018.
Dimension, Shape, Weight and Tolerances for
Continuously Hot-Rolled Steel Sheet and Strip
1 Scope
This Standard specifies the dimension, shape, weight and tolerance of continuously hot-rolled steel sheet and strip.
This Standard is applicable to the continuously hot-rolled steel strip produced by Baoshan Iron and Steel Co., Ltd.; as well as the steel sheet horizontally cut from the steel strip and the longitudinally cut steel strip, hereinafter referred to as steel sheet and strip.
2 Normative References
The following documents are essential to the application of 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) are applicable to this document.
GB/T 8170-2008 Rules of Rounding off for Numerical Values and Expression and Judgement of Limiting Values
3 Classification and Code
3.1 It can be divided as follows according to the edge state:
Trimming EC
Non-trimming EM
3.2 It can be divided as follows according to the thickness precision:
Ordinary thickness precision PT.A
Higher thickness precision PT.B
Advanced thickness precision PT.C
3.3 For the non-trimming steel sheet and strip, it can be divided as follows 1000mm in the longitudinal direction of the area no less than 40mm from the longitudinal edge of the steel strip to measure the maximum distance between the upper surface of the steel strip and the ruler.
7.4 Sickle curvature
The maximum distance BETWEEN the concave side of the steel sheet and strip AND the straight line connecting the two ends of the measurement part, as shown in Figure 2. For the steel sheet with length L < 5000mm, the measurement length of the steel sheet is the actual length. For the steel sheet with length L ≥ 5000mm, the measurement length of the steel sheet is any 5000mm.
7.5 Out-of-squareness (slanting)
The vertical projection of the horizontal edge of the steel sheet on the longitudinal edge (as shown in Figure 3); or one-half of the difference between the diagonals of the steel sheet.
8 Weight
8.1 The steel sheet is delivered according to the theoretical or actual weight; while the steel strip shall be delivered according to the actual weight.
8.2 When the steel sheet is delivered by the theoretical weight, the thickness used in the theoretical weight calculation shall be the average between the allowed maximum and minimum thickness; while the width and length shall take the nominal dimensions. Unless otherwise is specified in the product standard, the density shall be 7.85g/cm3. The theoretical weight calculation method is shown in Appendix A (Normative). 8.3 The weight of different types of products shall meet the provisions of Table 14. 9 Numerical Rounding-Off Rules
The numerical judgment is based on rounding-off comparison method. The numerical rounding-off shall conform to the provisions of GB/T 8170.