Time increment required is less than the minimum specified

[wieczor]

Hi all,
I need to your advice about solution of my problem in Abaqus.
Now I am making a model to check an influence and interaction beetween steel plate and steel gasket and steel nut. I made thi 3 parts - palte and gasket are a solid type and nut is a shell type. BC are applied to the shorter sides of the plate (displacent U1,U2,U3 = 0), at top of plate trzere is gasket and between those elements there is interaction - surface to surface contact with friction coefficient =0.2 and now when I put presuure to the top of the gasket and go through the job everything is OK but when I assembly the next part - nut- there is an error... I put the nut at the top of the gasket and I applied a contact between gasket and nut in the same way like between plate and gasket BC is the same and load is moving from top of gasket to top of nut... so this is a simulation of pressing nut in gasket and next to plate where plate is blocked for movement...and then where I am trying to submit the job there is an error like in the topic "Time increment required is less than the minimum specified"... The step type is static, general, time period is 1, incrementation is automatic with max number of increments 1000 there initial inc size is 1E-08, min inc size is 1E-09 and max 1... when im changing increment sizes the calculations are longer but the solution is the same... Please help!

 

[IceBreakerSours]

You should search the archives for error/warning messages. The time increment message, in reality, is a symptom, not the cause of your troubles. So, I wouldn't recommend reducing the time increment. Check the .dat/.msg files for clues.

Are you new to this forum? If so, please read these FAQ:

http://www.eng-tips.com/faqs.cfm?fid=376

http://www.eng-tips.com/faqs.cfm?fid=1083

 

[wieczor]

Thanks for answer, after I write a post I had read similar topics on this forum and there is no right solution for my warnigs... In monitor of my job there are that warnigs:

Slave surface assembly__pickedset224_cns_ is a node-based surface used with surface to surface approach. In order to obtain improved stress accuracy with this approach, an element-based surface should be used instead.

Slave surface assembly__pickedset226_cns_ is a node-based surface used with surface to surface approach. In order to obtain improved stress accuracy with this approach, an element-based surface should be used instead.

40 nodes may have incorrect normal definitions. The nodes have been identified in node set WarnNodeIncorrectNormal.

Slave node 5 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 6 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 7 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 8 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 9 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 11 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 13 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 14 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 15 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 16 instance nakretka-1 will not be tied to the master surface assembly__pickedset223_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 5 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 6 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 7 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 8 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 9 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 11 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 13 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 14 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 15 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

Slave node 16 instance nakretka-1-lin-1-2 will not be tied to the master surface assembly__pickedset225_cns_. The distance from the master surface is greater than the position tolerance value.

20 nodes are either missing intersection with their respective master surface or are outside the adjust zone. The nodes have been identified in node set WarnNodeMissMasterIntersect.

14 elements are distorted. Either the isoparametric angles are out of the suggested limits or the triangular or tetrahedral quality measure is bad. The elements have been identified in element set WarnElemDistorted.

Boundary conditions are specified on inactive dof of 100 nodes. The nodes have been identified in node set WarnNodeBCInactiveDof.

There are 2 unconnected regions in the model.

Displacement increment for contact is too big.

Displacement increment for contact is too big.

Excessive distortion at a total of 32 integration points in solid (continuum) elements

Displacement increment for contact is too big.

Displacement increment for contact is too big.

Excessive distortion at a total of 31 integration points in solid (continuum) elements

Displacement increment for contact is too big.

Displacement increment for contact is too big.

Excessive distortion at a total of 30 integration points in solid (continuum) elements

Displacement increment for contact is too big.

Displacement increment for contact is too big.

Excessive distortion at a total of 25 integration points in solid (continuum) elements

Displacement increment for contact is too big.

Displacement increment for contact is too big.

Excessive distortion at a total of 14 integration points in solid (continuum) elements

And I dont know why my model is wrong. I thought that this is a simple task only 3 parts with contact and thats all...