Brazil 2014ugm Pre Certification of Rops for Agricultural Tractors

Pre-certification of ROPS for tractors through CAE technology Igor Saveljevas Rodrigues - VirtualCAE

agricultural

Topics • • • • •

Company : VirtualCAE Federal Regulation Norm : ABNT NBR ISO 5700:2009 Agriculture companies Static analysis: – – – – – –

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Simplifications Contact Material Loads and boundary conditions Survival cell Results

Next steps

VirtualCAE

Federal Regulation

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Elaborated by the government Mandatory guidelines Worker health and safety NR-12 – Safety at work on machines and equipments NR-12 - Annex XI – Forest and agricultural machines and implements NR-31 - Safety and health at work on aquaculture, forest extraction, livestock and agriculture.

ROPS – Roll over protective structure Figure 1 – Tractor with or without ROPS ROPS

Reference : Massey Ferguson

Retrieved from : http://www.massey.com.br/produtos/tratores/serie-mf-2600/ (Mar, 2014)

ABNT NBR ISO 5700:2009 • • •

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Federal regulation do not determine norms Either procedures or methods Where? > Technical standards (ISO, ABNT...) ISO 5700:2009 Destructive testing – Static loads – Survivall cell –

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Certification of ROPS in case of tractor roll over

Agriculture companies •

Outsourcing : cabin

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Cabin is used on several types of tractors

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Outsourcing : virtual certification Destructive test

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Simplifications Figure 2 – ROPS test

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Reduce the solving time without changing the results

Reference : Agrital

Retrieved from : http://www.agrital.com/english/tecnicoUK.htm/ (Mar, 2014)

Static analysis : simplifications Figure 3 – Axis and transmission

Reference : ZF

Figure 4 – Rear support

Reference : the Author

Retrieved from : http://www.directindustry.com/prod/zf-maschinenantriebe/powershift-transmission-tractors-16154-653933.html (Mar, 2014)

Static analysis : simplifications Figure 5 – Elastic damper

Figure 6 – Front support

Reference : Brammer

Reference : the Author

Retrieved from : https://brammeronline.de/product/info/397007/name/MEGU_5718228_50NR11_KONUSLAGER_FREUDENBERG (Mar, 2014)

Static analysis : simplifications •

Small radius and holes

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Extraction of middle surface

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Assembly corrections Screws

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Simplification of some geometries

Static analysis : contact Figure 7 – Contact

Reference : the author

Static analysis : material Graphic 1 – AISI 1020 Stress-strain curve

Reference : MatWeb

Retrieved from : http://www.matweb.com/search/DataSheet.aspx?MatGUID=b58ee61a3745453a9232f7864abba74f

(Mar, 2014)

Static analysis : loads Table 1 - ROPS LOADS ID

Load

Criteria

Definition

1

Rear longitudinal

Energy

E = 1,4 x mass

2

Rear crush

Force

F = 20 x mass

3

Side transverse

Energy

E = 1,75 x mass

4

Front crush

Force

F = 20 x mass

ROPS must be approved in each test •The structure must not penetrate the survival cell •

Static analysis : loads Figure 8

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Loads

1°

2°

Rear Longitudinal

Rear Crush Reference : the author

Static analysis : loads Figure 9 – Loads

3°

4°

Side transverse

Front Crush Reference : the author

Static analysis : boundary conditions

Figure 10 – Boundary conditions

Reference : the author

Static analysis : survival cell Figure 11 – Survival cell

Reference : the author

Figure 12 – Standard specification

Reference : ABNT ISO 5700:2009

Static analysis Figure 13 – Final model

Reference : the author

Results Figure 14 – Deformation

Reference : the author

Results Figure 15– Energy probe B

A

A : Energy : rear longitudinal B : Energy : side transverse Reference : the author

Next Steps •

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Comparison between the real test and the virtual simulation Improve the virtual model to reduce the error between the tests Certify someday only by CAE technology

Questions???