plate bending in ANSYS 11 3

[aniket79]

Hi every one.......

I am facing problem with thin plate bending using ANSYS 11.0. Plate dimensions are as 180X120X0.7 mm(LxWxt). I want to bend this plate in 90 deg at length 30 mm from both ends to make c section and radius of bend should be 3mm. I tried it by using shell93 and shell181 but I got only 15 to 20 deg deflection approximately.

If anyone could help me I'd appreciated.

here is the code that I used for ansys analysis
finish
/clear
/prep7
/title, bending


!key points

k,1,0,0,0
k,2,50e-3,0,0
k,3,90e-3,0,0
k,4,120e-3,0,0
k,5,120e-3,0.7e-3,0
k,6,90e-3,0.7e-3,0
k,7,30e-3,0.7e-3,0
k,8,0,0.7e-3,0

! lines
l,1,2
l,2,3
l,3,4
l,4,5
l,5,6
l,6,7
l,7,8
l,8,1

!key point for circle
k,9,30e-3,3.7e-3,0

circle,9,3e-3,,,360

al,1,2,3,4,5,6,7,8
al,9,10,11,12

lesize,1,0,,10,1.0

et,1,shell93
r,1,0.7e-3
mp,ex,1,210e3
mp,prxy,1,0.3

esize,,0.1e-3
amesh,all


dl,2,1,uy,0
dl,2,1,roty,0
dl,3,1,uy,0
dl,3,1,roty,0
dl,4,1,uy,0
dl,4,1,roty,0
dl,5,1,uy,0
dl,5,1,roty,0
dl,6,1,uy,0
dl,6,1,roty,0

dk,2,uy,0
dk,2,roty,o
dk,7,uy,0
dk,7,roty,0
da,2,all

sfl,1,pres,10e3


/solu
antype static

solve
finish
/post1
plnsol,s,x

thank you

Aniket

 

[TERIO]

Here are a fer comments to think about:

- I there any reason you chose sfl,1,press,103e6 as the right load to deform it how you want?
- Saying you want it to bend 90 deg with a 3mm bend radius seems like a metal forming problem but it looks like you have only specified elastic properties (mp,ex,1,210e3; mp,prxy,1,0.3).

 

[Drej]

In addition, a few more points to think about:

1) Your analysis is linear elastic - this is not correct
2) You need to obtain elastic/plastic properties for this material and include as a true stress/strain table
3) You will need to enable nonlin geom
4) You will need to increment (time step) the solution appropriately
5) You will need to think about providing a release step at the end of the analysis to enable elastic springback


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[aniket79]

hi Terio and Drej...

thanks a lot

regards
aniket

 

[aniket79]

Hi everyone....

Finally, I managed to bend plate into 90 degrees using Ansys non-linear analysis. But problem is shell material is penetrating into roller (see figure).
how can I overcome form this problem? and other thing how can I calculate yield strength at the corners?????

(Its a cold metal forming problem)

Thank you
Aniket

 

[rb1957]

contact ?