UT D Substation Design A Brownfield Approach

Transcription

1 UT D Substation Design A Brownfield Approach Greg Nightingale SA Power Networks, South Australia. Learning Objectives Learn how to design in 3D with the intention to combine with existing substation drawings Learn how to configure Inventor drawings with existing CAD files Learn how to manage the BOM and parts lists ready for exporting to multiple Microsoft Excel sheets Learn how to design with reference data such as 2D CAD files, point clouds, and AutoCAD Civil 3D surfaces Description With Inventor software and the Substation Design Suite from AutomationForce, Inc., you can utilize existing CAD files to complete projects in 3D. Quite often it isn t financially viable to model an entire existing site, but you can still design your project in 3D and produce revised substation drawings, making parts of an existing station intelligent. Combining a new 3D model with existing 2D drawings enables utilities to benefit from the power of 3D design while saving time and money by eliminating the need to reverse engineer from site visits, redlines, and other information that is needed to piece together the current as-constructed state of a substation. This session will cover possible workflows and use cases for brownfield design, which include setting up new 3D models and drawings with legacy 2D data as well as managing an existing bill of materials to add, change, or delete items based on a project. Your AU Expert Greg Nightingale is a Primary Plant Design Team Leader for South Australia s electrical distribution company, SA Power Networks. He has been using Autodesk Inventor for nearly ten years and more recently the Substation Design Suite from AutomationForce. In 2014 Greg was assigned the task to manage his team through a 3D pilot which trialled the Substation Design Suite with Autodesk Inventor and Vault Professional.

2 Design in 3D with the intention to combine with existing substation drawings. Setting up the substation assembly. One of the first steps to designing a new 3D model within a brownfield site is setting up your model in a way that the old and new are referenced accurately to each other. In other words you want your 3D model to be in a precise position when creating the final drawings because the final drawings will be a revision to existing drawings. Modelling Guide Loading one or multiple existing drawings into the 3D substation assembly will create your reference or guide that can be used throughout the entire design. This can be either one or all construction drawings such as an equipment drawing, footings drawing etc. It needs to be noted that this drawing which is loaded into the substation assembly will not appear on the final Inventor drawing these steps are discussed in a later section. Firstly, attach the existing drawing file into an individual.ipt file by using the layout attach tool within the Substation Design Suite (Figure 1). This will require an existing empty.ipt file to exist within the substation assembly. The.ipt file is then placed into the substation assembly and can be constrained into position. FIGURE 1: LAYOUT IMPORT TOOL When constraining, use a feature that is common to all drawings such as datum lines or bus centre lines This will vary so it is managed on a case by case basis. The.ipt files containing the existing drawing can be turned on and off as required and also projected and constrained to. FIGURE 2: CAD FILE CONSTRAINED IN THE SUBSTATION ASSEMBLY 2

3 TIPS 1. Reduce the information in the drawing before importing to help computer performance. It is only for modelling purposes so less information is ok. For Example, no text or dimensions, just critical information. 2. You may only require one drawing For SA Power Networks it would be the Footings & Ducts drawing as it contains enough datum information. 3. Keep the.ipt file turned off as much as possible to increase performance. Level of Detail (LoD) At SA Power Networks the four main sets of construction drawings are the Equipment, Footings & Ducts, Earth Grid & Riser, and Earthing Connections. It is important to be able to turn various 3D components on and off depending on what drawing they need to be displayed. A method to do this is using Level of Detail. You can have a set of preconfigured Levels of Detail in a standard substation assembly file. Within the Substation Design Suite (SDS) settings, you can configure the tool to open a specific standard assembly file which is only for substation assemblies Refer to the next section Folder Structure (XML File). New Substation Project Opens a substation assembly Substation assembly with predefined Level of Details FIGURE 3: PREDEFINED LEVEL OF DETAIL 3

4 Folder Structure (XML File) For housekeeping and ease of set up you can program the AssyTree.xml file so that the new substation assembly file has a set of pre-named folders within the browser. As the designer adds to the model they can drag and drop into a suitable folder. These folders keep the model in a user friendly condition but more importantly when you set up a LoD you can right click on an entire folder and suppress it. It is this XML file which points to the Substation.iam file mentioned earlier. The file location is shown below; C:\Program Files\Automation Force\Substation Designer\AssyTree.xml LoD in Substation.iam Empty.ipt and.iam for later design Folders for housekeeping FIGURE 4: ASSYTREE.XML FILE 4

5 Bill of Materials (BOM) The last of the main requirements when setting up the substation assembly is managing the BOM. This can be a very difficult task, as you will be combining a new 3D designed BOM with an existing BOM. There is a dedicated learning objective based entirely on managing the BOM. Configuring Autodesk Inventor drawings with existing CAD files. Configuring Drawings The aim is to import an existing CAD file into an Inventor drawing with minimal computer performance issues and as little impact on the designer s efficiencies. Various Inventor drawing file types have unique benefits, plus there are multiple methods to which the existing file can be imported. But, some methods create significant problems later in the design process causing rework resulting in lost time. Below are some tips that will help save your computer s performance and give you the added ability to draft using AutoCAD. Inventor.idw or.dwg? When it comes to the drawing, the question is what file format -.idw or.dwg? To find the answer, you need to review the different methods that are available for importing the existing CAD files. Each of the importing methods have disadvantages including scale mismatch between the Inventor view and imported drawing, reduced intelligence between the Inventor view and imported drawing, and difficulty editing the imported drawing once imported into Inventor. A possible solution is to import the CAD file into an.ipt file and then place it into the substation model similar to the steps for setting up the substation assembly. You are then able to use the Get Model Sketches feature in the drawing to display the sketch from the.ipt file. FIGURE 5: RIGHT-CLICK, GET MODEL SKETCHES FROM AN.IPT FILE WITHIN AN INVENTOR DRAWING. 5

6 This fixes scale issues and allows snapping between the Inventor view and imported drawing but it introduces the biggest problem of all It causes the computer to melt down! If you are required to edit the existing imported drawing, for example move some text or delete some information, the.ipt file that is holding the CAD file (in a sketch) has to be edited. When you edit the sketch the computer will have difficulty as it tries to process all the information most likely you will give up waiting for it to perform simple drafting steps or the computer will simply fail to operate. The key benefit with an Inventor.dwg is it allows you to import an AutoCAD block plus you can synchronise between Inventor and AutoCAD to modify your existing CAD file. There is a significant performance benefit to using an Inventor.dwg with AutoCAD blocks therefore the best solution is to use an Inventor.dwg. AutoCAD Blocks Inventor can manage an imported AutoCAD block extremely well with very little impact on computer performance. Every construction drawing that needs revising as part of the project will be opened in AutoCAD and converted to a block. For other users like Microstation, the drawing files need to be saveas into a.dwg format first. The block is to contain all the required information including text, dimensions and item balloons, which are to appear on the final drawing. In other words, the block should look identical to the previous revision of the drawing. There is no need to include the existing drawing border and border text, as this information will exist in the Inventor drawing sheet. It is possible to edit the block in AutoCAD at a later date and changes will update within the Inventor drawing next time it is opened (Figure 9). Placing Inventor Views with Level of Detail Now the existing CAD file is ready to go in the form of an ACAD Block, you need to start putting the drawing together. The first step is to place the view of the 3D model. This is a basic Inventor operation; just place the top view of the substation assembly. During the process you select the required Level of Detail for whatever drawing you re creating. For example, if you re creating a footings drawing, select the footings Level of Detail that you created earlier during the design. 6

7 FIGURE 6: LEVEL OF DETAIL It can take a few moments to process this step but when the view is placed there shouldn t be any problems with performance. Placing AutoCAD Blocks When the Inventor view is in an approximate position on the drawing, the AutoCAD block can be placed. Use the Import AutoCAD Block option by right clicking on the AutoCAD Blocks folder in the model browser (Figure 7). Once you ve browsed to your block, select the required scale followed by placing it on the drawing sheet in an approximate position for now. You should find that this is surprisingly quick and Inventor can handle it very well. FIGURE 7: RIGHT-CLICK ON AUTOCAD BLOCKS FOLDER THEN IMPORT AUTOCAD BLOCK. 7

8 Drawing which contains the block. Required block and scale FIGURE 8: BROWSE TO YOUR BLOCK FILE AND SELECT SCALE. You will be faced with the problem of getting the Inventor view to line up precisely with the block. Because we chose to use an Inventor.dwg, we have the option to Open in AutoCAD where it is very easy to use the snaps in AutoCAD to position the block correctly. When you right click the AutoCAD block in the model browser and select Open in AutoCAD, Inventor will save then automatically open AutoCAD. When you have positioned the block accurately in AutoCAD, save and reopen in Inventor. 8

9 FIGURE 9: RIGHT-CLICK, OPEN IN AUTOCAD TO EDIT AUTOCAD BLOCK. If you need to edit the existing drawing such as removing information, repositioning text or dimensions, follow the same steps to open in AutoCAD and then edit the block. You now have the benefits of the more powerful drafting tools that are within AutoCAD to manage the existing drawing. Locking Views There is the slight risk that you accidently move the view or block causing them to no longer be aligned. AutomationForce have developed a small but handy tool, which remembers the location of the block. If you find you have accidently moved the block then you are able to reposition it back by selecting Update in the Annotate tab. FIGURE 10: LOCKING AUTOCAD BLOCK INTO POSITION 9

10 Manage the BOM and parts lists ready for exporting to multiple Excel sheets. The Bill of Materials (BOM) As mentioned earlier, this can be a very difficult aspect to modelling in a brownfield site. All Utilities will have varying degrees of difficulties with regard to managing the BOM. The following problems are related to SA Power Networks and may not be similar to other companies. At the very least it may give the users some ideas to solve other issues. SA Power Networks problems in this area are based around three factors; 1. The BOM is split into individual Excel material lists based on the Equipment, Footings, Earth Grid or Earthing Connections drawings. These material lists are then used for procurement and construction. Each material list starts from item number 1 therefore the Inventor BOM needs to have multiple Item 1s. For example, an item 1 for footings, an item 1 for equipment etc. 2. Being Brownfield, there is an existing Excel material list, which has item numbers that are already used. Therefore new 3D items either need to continue from the next available number or match an existing item number. For example, 100mm conduit could already exist in the yard at say item number 12; therefore any new 3D 100mm conduit needs to be item Exporting the BOM back into the existing Excel material list with minimal user manipulation. BOM Management To manage the duplicate item numbers, each item needs to be renumbered in the Inventor BOM. Renumbering items in the BOM is very easy but you may need to filter the BOM so that you have all the common components together such as footings. This will simplify the process so you can bulk renumber (Figure 12). Therefore creating a custom iproperty called BOM_Category will assist with filtering the BOM. SA Power Networks has four predefined BOM_Category values being Equipment, Footings, Earthing and Earthing Connections. These coincide with the four main drawings that we produce as mentioned earlier. All 3D parts and assemblies need to have the BOM_Category assigned to them (Figure 11). 10

11 FIGURE 11: CUSTOM IPROPERTY BOM_CATEGORY This then allows the designer to filter the BOM and then easily select all the Footings for example and renumber just those starting from the required number. FIGURE 12: FILTERED BOM & RENUMBER 11

12 Existing BOMs As mentioned earlier, a problem is managing items that already exist in the yard (EG the 100mm conduit). Therefore a new tool has been developed which allows the designer to import an Excel material list into Inventor, which in turn creates Virtual Components for each item. These Virtual Components create what could be considered a place hold for that item and item number. If the iproperties for the new and old 100mm conduit are identical (Part Number is most important), then Inventor will automatically manage the item numbers and quantities. FIGURE 13: BOM IMPORT TOOL 12

13 During the import process you can assign iproperties to columns that exist in the Excel sheet making the import tool quite powerful. For example, the Excel material list may have a column for stock numbers which can now be mapped to the Inventor iproperty Stock Number. Existing Excel data. Selecting an iproperty to assign to an Excel column. FIGURE 14: ASSIGNING IPROPERTIES Finally, now that the BOM includes all the existing items as well as the new 3D items, all in the correct numerical position, it can then be exported into a company s Excel material list template with no manipulation. 13

14 Design with reference data such as 2D CAD files, point clouds, and AutoCAD Civil3D surfaces Point Clouds There are two high level uses for having a point cloud file. 1. You can use it to convert point cloud into solid and reverse engineer the entire site This is time consuming. 2. You use the point cloud as reference information only. Based on the theme of keeping brownfield designs financially viable, the best approach is not to reverse engineer but instead load the point cloud into Inventor and design within and around it. The benefits to having a site scanned are great, including as-built validation, visual clash detection and safety clearance checking. The convenience of bringing reality to your computer can save a lot of time, money and guesswork. TIP Ensure the point cloud is registered with a local datum point. If the point cloud datum is many kilometres away EG the Australian Height Datum, then Inventor cannot not manage it visually. As-Built Validation Site scans help verify as-built data so a designer can cross check between the scan and the last construction release of a drawing. It is common to find things in the yard that were never designed or are in a slightly different location especially for very old sites. Small examples can be additional pits are installed, different fence positions or even unknown concrete spoon drains. Some problems don t seem significant but identifying the problem during design prevents unforeseen additional site works and unwanted phone calls. The example shown below in Figure 15 is a switching cubicle that has been constructed out of position and 180 degrees around the wrong way. No official site mark ups were sent back to the design office but this allowed the designer to update drawings accordingly. 14

15 Construction Drawing Laser Scan As built FIGURE 15: AS-BUILT VALIDATION Safety Checks Figure 16 shows the ability to measure between your proposed 3D model and the onsite plant reducing the chance of clearance breaches and additional rework during construction. It can also assist during the construction planning where machinery clearances are required or, for example, determining a suitable crane to clear overhead wires (Figure 17). 15

16 3D Substation Design A Brownfield Approach FIGURE 16: CLEARANCE CHECKING FIGURE 17: CONSTRUCTION CLEARANCE 16

17 AutoCAD Civil3D Surfaces Importing a 3D surface from AutoCAD Civil3D can add a lot of benefits when it comes to determining new footing levels during the design. It also gives the model a much more realistic appearance. On occasions a smaller brownfield project is unlikely to have a budget for civil works. Therefore you may be designing without a designed bench. FIGURE 18: IMPORTED CIVIL3D SURFACE Civil 3D File Some preperation is initially required in AutoCAD Civil3D. There will be existing survey points that can be imported into Inventor such as footings, fences etc. In addition to the survey points, the designer can add user defined points in AutoCAD Civil3D. Ultimately the designer will need a set of points to define the height location of the surface and a set of points to define the rotation of the surface. With that inmind, a possible workflow for a brownfield site would be to use the surveyor s points for an existing flat footing as the height datum. These would generally be the corners of a footing and need to include a Top of Concrete height value which is equal for at least three corners of the chosen footing. The designer can create (if they do not exist) points for the bus centre lines so that the rotation of the 3D surface can be constrained in the substation assembly. 17

18 Footing points & user defined points FIGURE 19: AUTOCAD CIVIL3D SURVEY FILE WITH USER DEFINED POINTS Once you have all required points in the survey file you need to export the Land XML (LANDXMLOUT) which will be imported into Inventor. The export needs to include the points and surface data of your choice. Select points and surface/s to export FIGURE 20: EXPORT LANDXML EXPORT POINTS AND SURFACE DATA. 18

19 Importing 3D Surface When the Land XML has been exported you then use the Import Surface tool in the Substation Design Suite. This tool will require the user to select an existing.ipt file or create a new one to hold the 3D surface. Refer to Figure 4 regarding predefined.ipt files which can be used to contain a 3D surface. During the import there is the option to select points to import which requires the selection of the user defined points. Additionally, there maybe one or multiple surfaces to import but this depends if there is a designed bench or just a natural surface. Multiple surfaces to select User defines points FIGURE 21: IMPORT SURFACE GEOMETRY OPTIONS 19

20 Constraining 3D Surface The.ipt containing the 3D surface needs to be constrained within the model accurately. This requires using the points that were exported from Civil3D. For simplicity the height points from the existing footing should be constrained to the X-Y plane in Inventor. They can be constrained to a dedicated work plane to allow for easy height changes but this can cause confusion. The user points that were defined as the bus and bay centre lines need to be constrained to user work planes or the origin work planes this will depend on how the substation model and 3D surface are positioned relative to the origin planes. 3x user defined height points constrained to the X-Y plane User defined points constrained to work planes for positioning and to stop rotation. FIGURE 22: CONSTRAINING 3D SURFACE 20

21 Footing Levels The last step is to determine the level of the new footings. During the design the designer needs to position footings so that new plant and old plant interface together accurately and as desired. With the 3D surface you are able to check the suitability of a footing and its depth, IE not too deep or not too shallow. This can identify if a standard footing needs to be modified to be site specific. Checking is a simple measurment from the top of the footing to the ground surface which will detail the amount of footing that is above the finished surface level (Figure 23). FIGURE 23: FOOTING DESIGN CHECK FOOTING HEIGHT ABOVE FINISHED SURFACE LEVEL. The final footing levels need to be referenced to a datum point of some type. In this case you chose an existing flat footing with a known level. We constrained the survey points from the Top of Concrete to the X-Y Plane (Figure 22). This makes the X-Y plane our datum. For Example - If the top of the existing footing is (metres above sea level) then the X-Y plane in the model will be the same. Therefore, all new footings need to be measured to the X-Y plane to calculate the final footing level or if done correctly the constraint offset value can be used. For Example, if the datum footing (and X-Y plane) is at and you offset the new footing by 0.08m. Then simple maths will make the new footing level at

22 Footing offset from the X-Y plane by 80mm FIGURE 24: FOOTING LEVEL DESIGN FOOTING OFFSET FROM X-Y PLANE. Summary 3D substation design is not just for the greenfield projects with a large design budget - it is achievable for smaller brownfield work. There is no doubt that designing for an existing site introduces unique complications but most are now manageable if not avoidable. Additionally, as Inventor users are now able to use site data such as laser scans and 3D surveys, 3D substation design is becoming a very accurate and safe approach. Hopefully with the steps that are outlined in this document you are able to address problems early in the design so that no rework is required. Please contact me if you have any questions or comments. greg.nightingale@sapowernetworks.com.au 22