Detail of NB/T 47065.2-2018

Introduction of NB/T 47065.2-2018

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. NB/T 47065-2018 consists of the following five parts under the general title Vessel support: ——Part 1: Saddle support (NB/T 47065.1-2018); ——Part 2: Leg support (NB/T 47065.2-2018); ——Part 3: Lug support (NB/T 47065.3-2018); ——Part 4: Bracket support (NB/T 47065.4-2018); ——Part 5: Support lugs with rigid rings (NB/T 47065.5-2018). This is Part 2 of NB/T 47065-2018: Leg support. This part is drafted in accordance with the rules given in GB/T 1.1-2009 Directives for standardization - Part 1: Structure and drafting of standards. This part replaces JB/T 4712.2-2007 Vessel support - Part 2: Leg support. The following main technical changes have been made with respect to JB/T 4712.2-2007: ——The normative references are updated; ——The application scope of leg support, the maximum tangent distance, specification, material and manufacturing technical requirements of shell are added/deleted and revised; ——The Clause "Design" is added, and the requirements for design temperature, corrosion allowance, material, allowable stress, working conditions and load combination are specified; ——Other relevant technical requirements are modified; ——The calculation method of leg supports in Annex A (Informative) is revised by reference to GB/T 50761 Code for seismic design of petrochemical steel facilities. This part was proposed by and is under the jurisdiction of the National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262). This standard is drafted by the Design Branch of National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China. This part is interpreted by the National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262). The previous editions of this part are as follows: ——JB/T 4712-1992; ——JB/T 4712.2-2007. Vessel support - Part 2: Leg support 1 Scope 1.1 This part specifies the structural type, series parameter dimensions, allowable load, material, manufacturing technical requirements and selection method of leg support (hereinafter referred to as "leg") of steel vertical vessel (hereinafter referred to as "vessel"). 1.2 This part is applicable to vessels directly installed on rigid foundation with nominal diameter of DN 300mm~DN 2 000mm. 1.3 This part is not applicable to occasions with pulsating fatigue failure. 1.4 This part does not give considerations to the additional bending moment from external pipelines or other equipment. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 700 Carbon structural steels GB/T 706 Hot rolled section steel GB/T 985.1 Recommended joint preparation for gas welding, manual metal arc welding, gas-shield arc welding and beam welding GB/T 1591 High strength low alloy structural steels GB/T 1804-2000 General tolerances－Tolerances for linear and angular dimensions without individual tolerance indications GB/T 8162 Seamless steel tubes for structural purposes GB/T 50761 Standard for seismic design of petrochemical steel equipment NB/T 47015 Welding specification for pressure vessels NB/T 47018 Technical permission of welding materials for pressure equipment YB/T 3301 The welded steel H-section 3 Symbols AΦ——the width of backing plate, mm; AX——the length of backing plate, mm; B——the side length of base plate of strut, mm; D——the parameters of anchor bolt hole center circle, mm; Db——the diameter of anchor bolt hole center circle (see Figure 1), mm; DN——the nominal diameter of shell, mm; H——the total height of vessel (see Figure 1), mm; H0——the supporting height (see Figure 1), mm; H0max——the maximum supporting height, mm; H1——the distance from the lower surface of the base plate to the top of the strut (see Figure 2), mm; KL——the load combination coefficient, taking 1.25; L——the tangent distance of shell (see Figure 1), mm; L0——the anchor bolt hole distance of strut, mm; LH——the length of strut, mm; Lmax——the maximum tangent distance of shell, mm; Q0——the maximum allowable load of a single leg (at the height of H0max), kN; RteL(Rt p0.2, Rtp1.0)—— the yield strength of material at design temperature (or 0.2%, 1.0% non-proportional extension strength), MPa; W——the height or width of H-section strut, mm; b——the side length of angle steel, mm; d0 ——the outside diameter of steel pipe strut, mm; db——the hole diameter of anchor bolt, mm; hf——the weld length, mm; l——the side length of cover plate, mm; l1——the side length of cover plate, mm; l2——the width of cover plate, mm; ns——the safety factor for determining the allowable stress of materials, ns≥1.5; q0——the design basic wind pressure, Pa; t——the design temperature of leg,℃; t1 ——the thickness of H-section strut web, mm; t2——the thickness of H-section strut flange, mm; δ1——the thickness of angle steel, mm; δ2——the thickness of steel pipe, mm; δa——the thickness of backing plate, mm; δb——the thickness of base plate, mm; δe——the effective thickness of cylinder at the joint of leg, mm; δmin——the minimum thickness of the cylinder at the joint of the leg without setting a backing plate, mm; δn——the nominal thickness of vessels, mm; [σ]te——the allowable stress of leg material at the design temperature, MPa; [σ]tbt——the allowable tensile stress of anchor bolt material at the design temperature, MPa; [τ]t——the allowable shear stress of leg weld at the design temperature, MPa; [τ]tbt——the allowable shear stress of anchor bolt material at the design temperature, MPa. 4 Type characteristics See Table 1 for the type characteristics of leg support.   Table 1 Type characteristics Type Support No. Backing plate Nominal diameter of applicable vessels DN/mm Support dimension Angle steel strut AN 1~6 None 300~1 300 See Table 2, Figure 2 and Figure 3 A Yes Steel pipe strut BN 1~6 None 600~1 600 See Table 3, Figure 4 and Figure 5 B Yes H-section strut CN 1~6 None 1 000~2 000 See Table 4, Figure 6 and Figure 7 C Yes 5 Series parameters and dimensions See Figure 1 for the structure diagram and leg arrangement of the vessel. The structural dimensions of Type AN and Type A leg supports are as specified in Figure 2, Figure 3 and Table 2. The structural dimensions of Type BN and Type B leg supports are as specified in Figure 4, Figure 5 and Table 3. The structural dimensions of Type CN and Type C leg supports are as specified in Figure 6, Figure 7 and Table 4.

Contents of NB/T 47065.2-2018

Foreword i 1 Scope 2 Normative references 3 Symbols 4 Type characteristics 5 Series parameters and dimensions 6 Design 7 Marking 8 Manufacture 9 Selection method Annex A (Informative) Calculation method of leg support