Detail of YB/T 4001.1-2019

Introduction of YB/T 4001.1-2019

Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. YB/T 4001 Steel bar grating and matching parts is consisted of the following three parts: — Part 1: Steel bar gratings — Part 2: Grating platform ball-type guardrails — Part 3: Grating stair treads This is Part 1 of YB/T 4001. This part is developed in accordance with the rules given in GB/T 1.1-2009. This standard replaces YB/T 4001.1-2007 Steel bar grating and matching parts, and the following main technical changes have been made with respect to YB/T 4001.1-2007: — adjustment of the chapter structure that Clause 6 Order content and Clause 8 Calculation of weight and area of steel bar grating are merged into Chapter 10 Order contract, weight, area and delivery settlement (see Clause 10; Clause 6 and Clause 8 of Edition 2007); — amendment of the technical requirements of raw materials for steel bar grating that "bearing bar may be made of Q235-A or B steel of GB/T 700" is changed to "bearing bar is made of carbon structural steels and high strength low alloy structural steels, and meets the requirements of GB/T 700, GB/T 1591 and GB/T 702; adopts austenitic stainless steel and duplex stainless steel materials, and meets the requirements of GB/T 4237 and GB/T 3280" (see 7.1; 9.1 of Edition 2007); — subdivision of the band of steel bar grating that includes trim band and load-carrying band (see 7.2; 9.1.3 of Edition 2007); — addition of inspection requirements and sampling rules (see Clause 9); — deletion of Annex A Stair treads that is merged into Part 3 of this standard: Grating stair treads (Annex A of Edition 2007); — deletion of Annex B Canal cover of steel bar grating (Annex B of Edition 2007); — adjustment of Annex C Test for Load and deflection that is changed to Annex A and modification of static load test of steel bar grating which is used as the specified inspection item of steel bar grating (see Annex A; Annex C of Edition 2007); — addition of Annex B Installation and fixing of steel bar grating (see Annex B); — amalgamation of Annex C Calculation of safe load and deflection of steel bar gratings from Annex D Calculation of imposed load and deflection of steel bar grating and Annex E Calculation of safe load and deflection (see Annex C; Annex D and Annex E of Edition 2007). This part was proposed by China Iron and Steel Association. This part is under the jurisdiction of the National Technical Committee on Iron and Steel of Standardization Administration of China (SAC/TC 183). The previous editions of this part are as follows: — YB 4001-1991, YB/T 4001-1998 and YB/T 4001.1-2007. Steel bar grating and matching parts Part 1: Steel bar gratings 1 Scope This standard specifies the terms and definitions, product structure, model and labeling, allowable deviation in dimension, technical requirements, design for use, test methods and inspection rules, order content, weight, area and delivery settlement, packaging, marking and quality certificate of steel bar grating. This part is applicable to steel bar grating (hereinafter referred to as “steel bar grating") for working platforms, floors, walkways, stair threads and trench covers in industries of petroleum, chemical engineering, metallurgy, light industry, shipbuilding, energy and municipal administration. Other types of steel bar grating and metal grating may also comply with the related requirements of this part. 2 Normative References The following referenced documents are indispensable for the application of this standard. For dated references, only the edition cited applies. For undated reference, the latest edition of the referenced document (including any amendments) applies. GB/T 700 Carbon structural steels GB/T 702 Hot-rolled steel bars — Dimensions, shape, weight and tolerances GB/T 709 Hot-rolled steel bars — Dimensions, shape, weight and tolerances and sheet GB/T 1591 High strength low alloy structural steels GB/T 3280 Cold rolled stainless steel plate, sheet and strip GB/T 4237 Hot rolled stainless steel plate, sheet and strip GB/T 13912 Metallic coatings - Hot dip galvanized coatings on fabricated iron and steel articles — Specifications and test methods GB 50009 Load code for the design of building structures GB 50017 3 Terms and Definitions For the purposes of this standard, the following terms and definitions apply. 3.1 steel bar grating plate steel member with open through hole fixed by orthogonal combination of bearing bar and cross bar according to certain length which may be divided into pressure welding steel grid and pressure locking steel grid according to different manufacture methods 3.2 bearing bar flat steel bearing load in steel bar grating 3.3 cross bar twisted square steel, round steel or flat steel fixed on bearing bar 3.4 clear opening maximum inscribed circle diameter of open through hole of steel bar grating 3.5 bearing bar centers distance between centers of two adjacent bearing bar 3.6 cross bar centers distance between centers of two adjacent cross bar 3.7 pressure resistance weld method of welding named pressure resistance welding, or pressure welding, which utilizes the resistance heat generated by the current passing through the contact surface of the joint and its adjacent areas where the pressure is applied through the electrode after the workpiece is assembled 3.8 band flat steel, angle steel, C-type steel, cross bar or other materials used as end bar for fixing at the ends, sides or the edges of other openings and notches of bearing bar of steel bar grating 3.9 trim band band of steel bar grating for changing appearance, not bearing and transmitting the load of bearing bar 3.10 load-carrying band band of steel bar grating that located at the special part of the platform where the bearing bar has no support and requires the end bar to bear and transfer the load of bearing bar 3.11 toe plate protective baffle fixed around a platform or in a steel bar grating with the edge of the opening or notch higher than that of the bearing bar 3.12 length maximum size of steel bar grating parallel to the direction of bearing bar 3.13 width maximum size of steel bar grating perpendicular to the direction of bearing bar 3.14 depth thickness of steel bar grating which equals to the width of bearing bar 3.15 span clearance of steel bar grating supporting frame parallel to the direction of bearing bar 3.16 grating design value of load load value of steel bar grating obtained by calculation based on the design value of bending strength of steel 3.17 design value of concentrated load at mid-span design value of concentrated load acting on the middle line of steel bar grating span 3.18 design value of uniform load at full-span design value of uniformly distributed load acting on the plane area of steel bar grating 3.19 allow of maximum deflection under load maximum allowable deflection in mid-span of steel bar grating under external load 4 Product structure 4.1 Pressure welding steel bar grating Steel bar grating fixed by pressure resistance weld at each intersection of bearing bar and cross bar are called pressure welding steel bar grating. Twisted square steel or round steel is usually used as the cross bar of pressure welding steel bar grating. As shown in Figure 1. Figure 1 Pressure welding steel bar grating Note: 1 — bearing bar 2 — cross bar 4.2 Pressure locking steel bar grating At each intersection of the bearing bar and the cross bar, the cross bar is pressed into the bearing bar with pre-grooved by pressure through the assembling method of interference fit, or deformed and fixed by bulging, forging and pressing and other methods. And the steel bar grating fixed by this way is called pressure locking steel bar grating which is shown in Figure 2.

Contents of YB/T 4001.1-2019

Foreword i 1 Scope 2 Normative References 3 Terms and Definitions 4 Product structure 5 Model and labeling 6 Allowable deviation in dimension 7 Technical requirements 8 Design for use 9 Test methods and inspection rules 10 Order contents, weight, area and delivery settlement Annex A (Normative) Static load inspection of steel bar grating Annex B (Informative) Installation and fixation of steel bar grating Annex C (Informative) Calculation of applied load and deflection of steel bar grating