轴式吊耳及尾吊强度计算



AX型轴式吊耳的计算

项目号 ITEM NO.

Calculation of Type AX Trunnion Lug

文件号 DOC. NO.

本计算书是参照HG/T21574-2018编制的。

说明:

This calculation sheet is prepared referring to HG/T 21574-2018.

1. 本计算书是参照HG/T21574-2018编制的，主要不同之处是增加了管轴与壳体连接焊缝的强度校核。（垫板与筒体连接焊缝应力值比管轴处低，故略去） 2. 黄色单元格内的数据是需要输入的。 3. 管轴与壳体连接焊缝根部宽度a的输入值应为焊缝根部的名义宽度减去负偏差，举例来说，如果图纸上标注的焊缝宽度为10±1mm, 则a的输入值应为9mm。 4. 设计者应根据轴式吊耳作用在垫板和壳体上的力和力矩（即本计算书中的Fv、Fh、M和M1），采用SW6或PV Elite的局部应力计算程序，对垫板及壳体中的局部应力进行校核。 应注意: 设备起吊时吊耳在垫板和壳体中引起的局部应力属于一次应力, 因此校核时局部薄膜应力和最大表面应力均不应超过1.5倍的材料许用应力。

1

输入数据 Input Data

设备起吊重量 Equipment lifting weight

Q =

70000

kg

轴式吊耳的数量 Trunnion number

n =

2

管轴材料 Material of trunnion

20

管轴的许用拉伸和弯曲应力Allowable tensile and compressive stress of trunnion material

[σ]=

150

MPa

管轴的许用剪应力 Allowable shear stress of trunnion

[τ]=

90

MPa

管轴外径 Diameter of trunnion

DO =

426

mm

管轴有效厚度 Effective thickness of trunnion

S =

18

mm

管轴长度 Length of trunnion

L =

248

mm

垫板厚度 Thickness of pad

S'=

16

mm

壳体材料 Shell material

Q345

管轴与壳体连接焊缝根部的宽度  Bottom width of groove

a =

18

mm

Weld attaching trunnion to shell

焊缝系数 weld coefficient

Φ=

0.7

钢丝绳与垂直面的夹角 Angle of sling

α =

15

°

动载系数 Dynamic factor

c =

1.65

A

t

5~10

5~10

5~20

10~25

DN

150

180

200

250

S =

10

12

14

14

L =

120

130

140

150

2

管轴强度校核 Checking strength of trunnion:

垂直力 Vertical force

Fv =Q / n×9.81×c=

566527.5

N

水平力 Horizontal force

Fh =Fv×tanα=

151800.59

N

纵向弯矩 Longitudinal bending moment

M =Fv×L=

1.40E+08

N·mm

管轴横截面积 Cross-sectional area of trunnnion

A =π×(DO-S)×S=

23071.86

mm2

管轴内外径比值 Ratio of inside diametr to outside diameter

α=(DO-2S)/DO=

0.92

管轴的惯性矩 Moment of inertia

J =π×DO4×(1-α4)/64=

4.81E+08

mm4

管轴的断面模数 Section modulus

W =J / (0.5DO)=

2.26E+06

mm3

2258279.8

拉伸应力 Tensile stress

σLt =Fh / A=

6.58

MPa

弯曲应力 Bending stress

σLb =M / W=

62.21

MPa

组合应力 Combined stress

σL =|σLt| + σLb=

68.79

MPa

σL ≤ [σ] , 管轴组合应力校核合格，the combined stress in trunnion is satisfactory.

剪切应力 Shear stress

τ =Fv / A=

24.55

MPa

组合应力 Combined stress

σC=sqrt(σL 2+τ2)=

73.05

σC ≤ [σ] , 组合应力合格，it is satisfactory.

3

耳轴与端板连接角焊缝强度校核 Checking strength of weld of trunnion to end plate:

剪切应力 Shear stress

τh =Fh / 1.76SDO=

11.25

MPa

τh

≤

0.7[τ]

合格,It is safe

4

轴耳与筒节连接角焊缝强度校核 Checking strength of welds of trunnion to shell

焊缝底部的外径 Outside diameter of root of weld

DO1=DO+2a=

462

mm

焊缝根部的内外径比值Ratio of inside to outside diameter of weld root

α1=DO/DO1=

0.92

焊缝根部的截面积 Sectional area of weld root

A1=π×(DO1-a)×a=

25107.61

mm2

焊缝根部的惯性矩 Moment of inertia of weld root

J1=π×DO14×(1-α14)/64=

6.20E+08

mm4

焊缝根部的断面模数 Section modulus of weld root

W1=J1/(0.5DO1)=

2.68E+06

mm3

弯矩 Bending moment

M1=Fv×(L+S')=

1.50E+08

N.mm

焊缝的拉伸应力 Tensile stress of weld

σwt=Fh/A1=

6.05

Mpa

焊缝的弯曲应力 Bending stress of weld

σwb=M1/W1

55.75

Mpa

焊缝的组合应力 Combined stress in weld

σw=σwt+σwb=

61.80

Mpa

σw

≤

[σ]

合格,It is safe

焊缝的剪切应力 Shear stress of weld

τw =Fv/A1=

22.56

MPa

组合应力 Combined stress

σwc=sqrt(σw+τw)=

65.79

MPa

σwc

≤

[σ]

合格,It is safe