interference fit analysis

Sid_22073

Hello,

Kindly explain how can I make an Interference analysis in SIMLAB or in Hypermesh optistruct

		Toleramces		Tol/class	Final dim
	Dia(mm)	Max	Min		Max	Min
Crank_Pin dia	25	0	-0.009	h5	25	24.991
Hole dia	25	-0.1	-0.135		24.9	24.865
Interference	Min	0.091
	Max	0.135
	Avg	0.113

 

If you have some example problem will be great.

or If you could refer me for some tutorial will also be helpful

 

Kind regards,

SId

Adriano_Koga

Sid_22073 said:

Hi Adriano,

Thanks for the answer.

Currently 

THe physical CAD geometrie are at zero clearance.

For max clearance 

so the interference is 0.135 which I want to use.

Can you please explain is there any other parameter I should specify in PCONT card ?

Do I need to perform a Nlparam ?

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
PCONT	PID	GPAD	STIFF	MU1	MU2	CLEARANCE	SEPARATION
	FRICESL

 

I also want to include a static pressure subcase as combine with this Interference fit. So How can I go do this. Can you please explain

Kind regads

SId

you can include clearance directly in your CONTACT card.

For NL analysis you need NLPARM

Adriano_Koga

interference analysis is performed by just adding contacts between your components.

From these contacts, you could perform interference, 2 ways;

 

#1 you model/mesh having penetration/interference, thus the solver will need to remove this penetration during the NL analysis

#2 you don't need to have actual mesh penetration, but you could add artificial interference by adding 'Clearance' in your contact pair. I.e: defining negative clearance -0.1 will numerically tell the solver that there is a penetration that need to be removed from the contact, even if the nodes are not touching initially.

Sid_22073

Hi Adriano,

Thanks for the answer.

Currently 

THe physical CAD geometrie are at zero clearance.

For max clearance 

so the interference is 0.135 which I want to use.

Can you please explain is there any other parameter I should specify in PCONT card ?

Do I need to perform a Nlparam ?

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
PCONT	PID	GPAD	STIFF	MU1	MU2	CLEARANCE	SEPARATION
	FRICESL

 

I also want to include a static pressure subcase as combine with this Interference fit. So How can I go do this. Can you please explain

Kind regads

SId

Adriano_Koga

Sid_22073 said:

Hi Adriano,

Thanks for the answer.

Currently 

THe physical CAD geometrie are at zero clearance.

For max clearance 

so the interference is 0.135 which I want to use.

Can you please explain is there any other parameter I should specify in PCONT card ?

Do I need to perform a Nlparam ?

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
PCONT	PID	GPAD	STIFF	MU1	MU2	CLEARANCE	SEPARATION
	FRICESL

 

I also want to include a static pressure subcase as combine with this Interference fit. So How can I go do this. Can you please explain

Kind regads

SId

you can include clearance directly in your CONTACT card.

For NL analysis you need NLPARM

Sid_22073

Hi,

THanks I could run the sumulation with your suggestion.

I have run nonlinear static analysis with load case which combine the contact interferece fit at the pin shown below and also the pressure load at other location in the assembly.

How to interpret the contact results. In my simulation I see very high contact pressure at the interference fit contact location.

I want to evaluate only the contact pressure due to interference fit.

so can I take these results as contact pressure.

What does this high pressure results tell, i mean how to interpret ?

Am I running correct with contact and pressure load together in one single subcase ?

 

Sid_22073

Hi,

one more thing I forgot. 

In the displacement results, i can see the pin is moving along the axis direction ( X- Axis).

Do I need to contraint the pin in the simulation.

In the real asembly, the pin is assembled by an interference fit. so bascially it does not move.

Kind regards.

SId

Adriano_Koga

Sid_22073 said:

Hi,

one more thing I forgot. 

In the displacement results, i can see the pin is moving along the axis direction ( X- Axis).

Do I need to contraint the pin in the simulation.

In the real asembly, the pin is assembled by an interference fit. so bascially it does not move.

Kind regards.

SId

if you want to evaluate only interference first, create a 1st step with only contacts, and no loads.

Then add a 2nd loadstep, with the pressure continuing from the 1st one.

Sid_22073

Hi Adriano,

Good Morning !!

After succesfully completing the contact analysis.

next, I want to find the torque required for the slip of the interference fit.

I saw some of your previous post, but could not understand fully.

Could you please provide me any short sample opristruct deck (.fem file).

So I can repeat the same.

THanks for the help.

Looking forward for your reply.