NB/T 47065.2-2018Vessel support - Part 2: Leg Support (English PDF)

1 Scope

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

APhi - - 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,°C;

t1 - - the thickness of H-section strut web, mm;

t2 - - the thickness of H-section strut flange, mm;

delta1 - - the thickness of angle steel, mm;

delta2 - - the thickness of steel pipe, mm;

deltaa - - the thickness of backing plate, mm;

deltab - - the thickness of base plate, mm;

deltae - - the effective thickness of cylinder at the joint of leg, mm;

deltamin - - the minimum thickness of the cylinder at the joint of the leg without setting a backing plate, mm;

deltan - - the nominal thickness of vessels, mm;

[sigma]te - - the allowable stress of leg material at the design temperature, MPa;

[sigma]tbt - - the allowable tensile stress of anchor bolt material at the design temperature, MPa;

[tau]t - - the allowable shear stress of leg weld at the design temperature, MPa;

[tau]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.