Guide · Plant 3D
Getting a Plant 3D piping MTO when you only have the NWD
Short answer: without the Plant 3D project you cannot run its reports or isometrics. But an NWD exported from Plant 3D usually still carries the part data an estimator needs — class, port sizes, pipe length, spec, line number, descriptions and the isometric symbol key. A take-off built from those properties, grouped by line and counted once per object, is enough to price from — as long as you also write down what the model did not tell you.
Why you only have the NWD
The designer keeps the Plant 3D project. What reaches the contractor at tender is the coordination model: a Navisworks NWD, often a federation with structure, building services and equipment appended alongside the pipework. Plant 3D’s own MTO routes — Report Creator, the Data Manager export, the bill of materials on an isometric — all need the project and its drawings. Asking for them takes time you rarely have inside a tender window, and sometimes the answer is simply no.
The good news is that Plant 3D is generous with properties. Select a pipe in Navisworks, open the Properties window, and you will usually find a tab full of the same fields the Plant 3D reports would have used.
What survives into the NWD
These are the fields worth looking for. Names are as Plant 3D publishes them; whether each one is filled in depends on the catalogue and on the designer.
| Property | What it gives you | Watch for |
|---|---|---|
| Class | Item type: Pipe, Elbow, Tee, Reducer, Flange, Valve, Olet, Coupling | Instruments and supports sit in the same tree — decide scope |
| Port1/2/3 NominalDiameter | Every end size, so both sizes on reducing items | Size alone may only give the larger end |
| Length | Pipe length on pipe segments | Must be mapped before Quantification shows it |
| Line Number | The line each part belongs to | Blank, or a placeholder value |
| Spec | Piping class | A fair fallback grouping when lines are missing |
| ShortDescription, Long Description, PartSizeLongDesc | Sub-type: valve type, flange type, pressure rating | Can be empty on perfectly good parts |
| ContentIsoSymbolDefinition | Isometric TYPE= and SKEY= codes | Sometimes the only place the flange type is written |
| Material Code, Plant Material | Material split for procurement | Short codes such as “SS” or a DIN material number |
Gaskets and bolt sets travel inside the connector objects between flanges rather than as parts of their own. Their descriptions usually carry the nominal size (“Gasket, Flat, 50 ND”), so they can be counted by size if your client wants them in scope.
What does not come across
Anything Plant 3D produces when it runs the isometrics — weld numbers, spool numbers, cut-piece lists, the iso bill of materials — is not a property of the 3D parts, so do not expect to find it in the NWD. If the bid needs those, either price them separately or ask the designer for the isos. A take-off from the NWD is a component MTO: metres of pipe and counts of everything else.
Building the MTO line by line
- Check the properties before anything else. Click a pipe, an elbow, a reducing tee and a flange. If those fields are there, you have a take-off. If the objects are plain geometry with no class or size, no tool can count them reliably — say so early rather than estimating.
- Choose the line key. Use Line Number where it is real. Where it is blank or a placeholder, fall back to Spec, then to the source drawing — and write on the take-off which one you used.
- Count each object once. Plant 3D parts carry a GUID. In a federation the same pipework can be appended twice; counting by GUID stops it doubling. Our note on duplicate pipes in federated models covers this in detail.
- Pipe in metres.Sum Length per line and per nominal size, and convert from the model’s units. If a run reads zero, the property is not mapped — see why Navisworks shows zero-length pipes.
- Fittings each, sized from the ports. A tee or reducer whose ports differ is reducing and needs both sizes on the row. Decide that from the port diameters, not the name — catalogue abbreviations vary, including in case.
- Flanges by type. Read weld neck, slip-on or lapped from the description; when the description is empty, the SKEY in the isometric symbol field usually still says it.
- Valves by type and size. The long description gives the type and pressure rating; the ports give the size.
- Material where the model says it. Map the material code to carbon or stainless. Where nothing is published, leave it unknown — do not assume from the spec name.
- List what you could not classify. The parts left over are as important as the totals. They are where the pricing risk sits.
Doing it in Navisworks, or with Metriq
Navisworks Quantification can do this from the same properties: map Length and the size fields, build search sets on Class, and export to Excel. Our guide to piping take-off in Navisworks walks through where that set-up time goes.
Metriq MTO is one alternative. You upload the NWD — up to 300 MB — choose which source models belong in the bid, and download a line-based MTO in your client’s Excel schema, with an evidence report. Pipe is reported in metres, fittings and valves in each, duplicates across the federation are counted once, and anything the model cannot evidence is listed rather than invented. On a Plant 3D export the line column is read from Line Number; where that is blank, rows are grouped by spec or by source file and the workbook’s Method sheet says which. A single file costs £100, or £200 a month on subscription, both excluding VAT. If the take-off then needs to go into an estimating system, see moving an MTO into Trimble estimating.
Questions estimators ask
Can I run the Plant 3D MTO report or isometrics from an NWD?
No. Report Creator, the Data Manager and isometric production all work on the Plant 3D project and its drawings. An NWD is a Navisworks file: it carries the part properties, not the project. You build the take-off from those properties instead.
Which Plant 3D properties come through into Navisworks?
Usually the class, size and port nominal diameters, pipe length, spec, line number, short and long descriptions, material code and the isometric symbol key (SKEY). Which of them are actually filled in depends on the catalogue and on how carefully the model was kept.
What if the Line Number field is blank?
Group by Spec instead, or by source drawing, and say so on the take-off. A blank line number, or a placeholder such as 12345, is not a line — treating it as one produces lines with a single part on them.
Why do my Plant 3D pipe lengths read zero in Navisworks Quantification?
Quantification does not measure geometry; it reads properties. Plant 3D publishes the pipe length as a Length property, and until that property is mapped to the take-off field the row reads zero.
Only got the NWD? Upload it, tick the source models in scope, and get a line-based piping MTO with everything it could not measure listed beside it.