Material -...
Transcript of Material -...
![Page 1: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/1.jpg)
![Page 2: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/2.jpg)
Material
Function of welds
Static, dynamic(cyclically) loaded structure
Loading conditions
Fully loaded welds?
Working environment
Precision of the part - Distortion, inner tension
Productivity, Costs
On site, jobshop welding
On following figures answer
![Page 3: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/3.jpg)
![Page 4: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/4.jpg)
![Page 5: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/5.jpg)
![Page 6: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/6.jpg)
Function of welds - Static, dynamic loaded structure
Loading conditions
Working environment
Precision of the part
Productivity, Costs
Accessibility for welding-On site, jobshop welding
Welding process to be used
Material type
Code Requirements
Cost
To consider for design of Welded structure
![Page 7: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/7.jpg)
No weld is best
Smaller better than big
Humidity, atmosphere is welders enemy
Think how the stress pass through structure
Simple rules for design of Welded structure
![Page 8: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/8.jpg)
Load Failure mode Calculation
Static load Plastic deformation, Fracture, SCC
Ductile SHEAR failure
Re - Static safety coef. ,
Transition curves, SCC
Static, Dynamic,
Impact load
Fracture brittle
|Brittle TENSILE failure
Re –safety coef., CTOD,
Transition curves
Dynamic,
cyclical load
Fatigue – low, high cycle S-N (Wohler), Smith diagram
Thermodynamic
load
Creep Deformation -Time diagram
Wear
Corrosion SCC
![Page 9: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/9.jpg)
1. calculation not needed
◦ Static load
◦ Full penetration butt weld: s=t
◦ Recommended size of fillet weld: a=0,7*t
◦ Well weldable material – S235
◦ Weld quality check done
2. Existing stress compared with stress limit
◦ Static, dynamic
3. Calculation acc. Codes, standards – EN
1993, AISI
4. FEM simulations
![Page 10: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/10.jpg)
P/S=P/(2a*l)Double side weld
𝜏 = 𝐹/(𝑙 ∗ ℎ) 𝜏 = 𝐹/(𝑙 ∗ 𝑎)
σ 𝑟 =𝑀
𝐽∗r σ 𝑟 =
𝑀
𝐽∗r
𝜏 𝑟 =𝑀
𝐽∗ 𝑟
![Page 11: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/11.jpg)
Combined stress state - Theory of plasticity
Τmax HMH theory
𝜎𝑟𝑒𝑑2 = 𝜎𝑐𝑜𝑚𝑏
2 + 4𝜏𝑐𝑜𝑚𝑏2 𝜎𝑟𝑒𝑑
2 = 𝜎𝑐𝑜𝑚𝑏2 + 3𝜏𝑐𝑜𝑚𝑏
2
Stress limit ◦ Based on Re reduced by safety factor (e.g. 1,5 - 3),
◦ MOST OFTEN allowable stress = Re/1.5
◦ or calculated from tensile strength
![Page 12: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/12.jpg)
![Page 13: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/13.jpg)
Tensile stress in notched specimenEqual tensile stress
𝜎𝑚𝑎𝑥 = 𝜎 ∗ 𝛼𝜎 = 𝐹/𝑆
![Page 14: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/14.jpg)
Welds are non-homogenity in structure, welds
differ from WM in mictrostructure and stress
Possible is also presence of weld defects
![Page 15: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/15.jpg)
Even if reaction of welded structure on outer force is
same as for non-welded structure, inner stress state
is significantly different
![Page 16: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/16.jpg)
Good force transfer
High load capacity
Dynamic loading – full penetration weld
Difficult edge preparation
![Page 17: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/17.jpg)
![Page 18: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/18.jpg)
Load carrying in bending
Easy execution
a increase difficult
Risk of weld quench
![Page 19: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/19.jpg)
![Page 20: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/20.jpg)
![Page 21: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/21.jpg)
Different strength of pipe branches for pressure vessels
A-risk of material delamination, easiest
C-the strongest, demands neck forming
![Page 22: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/22.jpg)
Localized heating – uneven temperatures – heat cycle
Change of volume and mechanical properties with temperature
Lauwarmumformung von Stahl -
Mathias Liewald, Christian
Mletzko, Thorben Schieman
![Page 23: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/23.jpg)
![Page 24: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/24.jpg)
Localized heating
Thermal expansion
Decrease of mech properties
Material upsetting
Cooling
Thermal shinking
Increase of mechanical properties
Fixed Fixed
![Page 25: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/25.jpg)
Distortion
Transversal
Longitudinal
Angular
![Page 26: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/26.jpg)
Influence on distortion, stress
Weld size, length
Material – steel, stainless, Al
Weldment rigidity
Fixtures rigidity
Welding steps
Machining allowances
Heat treatment
![Page 27: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/27.jpg)
Figure 29.11 Residual stresses developed during welding of a butt joint. Source:
American Welding Society.
![Page 28: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/28.jpg)
![Page 29: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/29.jpg)
Continuous welds - sealing
Intermittent welds – less distortion
Dynamic loading – root quality, ceramic
Rigidity x flexibility
![Page 30: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/30.jpg)
ISO 13920 specifies 4 tolerance classes - A-D
linear, angular, and E-H for straightness, flatness,
parallelism
The tolerance class is indicated as ISO 13920-BE
Other tolerances can be indicated as well
![Page 31: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/31.jpg)
![Page 32: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/32.jpg)
![Page 33: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/33.jpg)
![Page 34: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/34.jpg)
![Page 35: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/35.jpg)
![Page 36: Material - u12133.fsid.cvut.czu12133.fsid.cvut.cz/assets/subject/files/137/TJC-Lecture-08-Design-of...Function of welds - Static, dynamic loaded structure Loading conditions Working](https://reader030.fdocuments.us/reader030/viewer/2022041222/5e0b88240e3aaa6222460e20/html5/thumbnails/36.jpg)