Shop Deliverables

Exporting Data Files

The Story so Far;

What are the industry norms and expectations regarding the checking status and quality assurance responsibilities of NC data and DXF files that are issued by steel detailers?

Is it the detailer’s responsibility to check dxf files prior to sending it to the fabricator?
Is it the responsibility of the fabricator to check them against the pdf files on receipt?
Is it the responsibility of the machine operator to check them when fabricating the plate using both the pdf drawings and the dxf files?

These were questions posed to the ACMA board in order to provide some clarity, not only to our members but to the broader steel fabrication industry.

The Issues

Along with the evolution of beamline machines and CNC plate cutting machines came the requirement to program these machines using the data extracted from the 2D detailed drawings. At a similar time, the evolution of planning, tracking, and managing progress started to take off, generally using report data again lifted from 2D detailed drawings. Shops would have teams of people programming these machines or software’s in an effort to automate and streamline fabrication processes. These days with the evolution of 3D modelling packages, Construction Modellers have the ability to export lots of different types of data files which are directly imported into management software’s and machines with little additional manipulation. This includes data files for process management software’s like Fabtrol, Strumis, Power Fab etc. and production automated software’s for cutting, drilling & welding of steel material (DSTV, DSTV+, iDSTV+, NC, DXF, Peddimat, STP & XML files etc.). As technology evolves, the information required by machines and their software is getting more and more, with some machine software’s already directly linking to the 3D modelling packages.

Although data files can be exported from 3D modelling packages, the files themselves often need to be opened in proprietary software for viewing, inspecting or processing. These proprietary software’s make it difficult for parties like the Construction Modeller who may not have access to the specific machines or licences to all the various products, to be able to view and inspect the data within the files. As a result, the responsibility of the data within the files, how they are set-up, exported and viewed must be a shared responsibility between the entities requesting the files (fabricator or machine operator) and the Construction Modeller building the 3D model.

The Response

Here is an industry framework as to how the responsibility is to be shared between Fabricators/Machine Operators and Construction Modellers.

Fabricator / Machine Operator requesting and using the data files

All data files requests and applicable settings are to be provided at the beginning of the project. This will allow the Construction Modeller the best ability to apply the various settings and technics to achieve the requested delivery and accurate outcome. Having to make changes to settings for data exports throughout the project may have significant impacts on schedule and cost as it may inadvertently work to be repeated. Settings include but are not limited to the following:

Management Software’s

The Type of file required
Profile designations
Material designations
Additional Data (attributes) requirements. Sequence, lotting, cost codes etc
Assembly, sub assembly, part data requirements
How data is to be supplied i.e. export is run per submittal or entire model
Any special requirement on how to run or complete the export

Machine Cutting Files (NC or DXF)

Limitations of the machines i.e. size of material, cope depths adjacent to beam flanges, holes sizes in a single member face
Are files to be categized to suit different machines
Internal corner cut requirements
How holes are to be treated i.e. flame cut or drilled
Line types
Pop marking, scribing, etching

Welding Fields

Machine access requirements i.e. angles and clearances
Weld Size or Weld type limitations of the machine

Review the data files within the proprietary software to ensure the outcome matches the 2D detailed drawing or controlled reports. The proprietary software and machine setting can cause files to appear different to the 2D detailed drawings generally as a result of incorrect setting being applied at the beginning of the project.
Any nesting of material is solely the responsibility of the Fabricator / Machine Operator.

Construction Modellers

Implement and test any setting requirements provided by the fabricator or machine operator at the beginning of the project.
Methods of modelling consider the export of data files.
- Optimizing material.
- Material is sufficient for any post processing that is required. E.g. material is not cut too short, or holes are made too big for sat tapping, machining requirements.
Limitations of machines are well known so that these can be applied to the 3D model to the best of their ability within the design parameters.
Data files exported are of the correct pieces and for the correct project.
If possible, some inspections are carried out with generic software’s (there still may difference to the proprietary software being used).
A higher level of care and review for parts like rolled or bent material to ensure the output is correct. The accuracy of holes and cuts in this material should be considered during the modelling process as rolling and bending distort the material.
Material that has a specific side like checker plate, should have consistently appearance with the specified side (i.e., either near or far side but not both).

When it comes to software that requires a direct link to the 3D modelling software package, the responsibilities are very similar to that laid out above however there are some differences.

Ownership of the model
When models are provided and the data within the model at that time
Who is responsible for selecting the pieces to export.

The 2D detailed drawing still has an important role, as the data files can be manipulated either by accessing the code or within the software’s. Also, while the machine abilities are improving with technology there is still often times where material still requires a manual post process to occur e.g., bevelling, machining, tapping, bending. It is for these reasons that the 2D detailed drawings (generally in PDF form) are the controlling document being supplied from the Construction Modeller for the purposes of fabrication. Maybe one day these machines will be so intelligent that 2D drawings won’t be required at all.

Although these data files can be exported from the 3D packages the time to apply the correct steps, test, and the processing for exporting the files all increases the work required by the Construction Modelling Team. This should be acknowledged by the construction industry and if required the compensation be provided to the Construction Modeller for these additional services. Any amount of compensation for this data would be significantly less than the effort it would take to manual program the software’s from the 2D detailed drawings.

Standard Shop Detailer Deliverable Examples

Hard copy only
Hold Down Bolt details & layouts
Marking plans for erection of structural Steel
Fabrication shop detail drawings
Field bolt lists & summaries
Noting of surface treatment requirements
DWF, Excel, PDF & DXF files available
Fitting Sheets drawn to scale
CNC Data files for shafts available in DSTV format
CNC Data files for plates available in DSTV or DXF format
Isometrics Arrangements
Report files such as Material List, Assembly List, Parts List, Assembly Parts List, and Handrail List available in comma delimited or PDF format

Bar-coding on drawings
Report files such as Material List, Assembly List, Parts List, Assembly Parts List, Handrail List available in customisable comma delimited files for import into programs such as Microsoft Access, Excel etc.
3D model available for statusing in proprietary software eg, Tekla Structures, Strucad, Pro-steel etc.
Web viewer model available for project management tool
SDNF file transfers available
CIMsteel
IFC – (3D software integration referencing file)
3D DXF
3D DGN

With the responsibility being shared between the entities requesting the files (fabricator or machine operator) and the Construction Modeller, any errors because of the data should be investigated thoroughly. It should be identified at what stage the error occurred and if all the necessary information was available to prevent the error from occurring in the first place. Construction Modellers can only work with the information available to them and they should not be assumed to be industry experts in every management or machine software involved in the construction industry.

After taking all the above into account, the board has prepared a shop deliverables summary for industry consideration and feedback.

Download the ACMA Shop Deliverables summary

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