In line components are easy to treat as the afterthought. The pipe is run, the equipment is in, and now you drop a valve here and an instrument there to finish the line off. But these are the parts the plant is actually operated through: the valves your operators isolate on, the instruments they read, […]
In line components are easy to treat as the afterthought. The pipe is run, the equipment is in, and now you drop a valve here and an instrument there to finish the line off.
But these are the parts the plant is actually operated through: the valves your operators isolate on, the instruments they read, the filters and meters they maintain. They are also the parts your records drift from most, because over a plant’s life valves get swapped, instruments get added and lines get isolated, and almost none of it gets drawn up afterwards. In the model, in line components are where the picture meets day to day operation, and where being wrong has the sharpest consequences.
A valve in the wrong place, at the wrong rating, or carrying no data is not a small error. It is an isolation plan your operators cannot trust, a valve schedule that does not match the field, and maintenance ordering the wrong replacement. In the model itself, a component that will not connect leaves a broken line and a bill of materials that is quietly wrong.
If you own the site, that is a valve and instrument register you cannot lean on for isolation, safety or compliance. If you engineer the site, it is you fighting a component that refuses to connect, chasing down a valve’s rating, and explaining why the model does not match what is bolted in out there.
This article is about the valves, meters, instruments and filters that sit in the line. The pipe and its fittings we covered in the piping article. What makes these in line components useful is what makes the rest of the model useful: they are spec driven and they carry data.
Placement is quick once the spec is built. Lift a component from the tool palette, or check the spec viewer to confirm you hold it in the size you need, then drop it onto a line, the end of a line, or a flange or nozzle, and Autodesk Plant 3D adds the right connections. It also sizes the component for you: drop an eight inch ball valve onto a two inch line and, as long as it is in your spec, it matches the line automatically.
Each component then carries its data. Size comes from the line or nozzle it sits on. Rating, material and manufacturer come from the spec, and can be overridden in the properties when you need to. You can add custom properties too, such as flagging whether a valve is on a pump suction or discharge. How far you take that data comes back to what you want the model to do for you.
Components connect when their end type, rating and fasteners match what the spec holds. When one refuses, it is almost always one of three things: you do not hold it in the right size, you are missing its gaskets or bolt sets, or the diameter or pressure class does not match. The spec can insist every component comes from the one spec, though in reality two are sometimes paired, a 300lb strainer on a 150lb line for example, and that can be allowed for.
Two details worth knowing. Each 3D component also holds a 2D symbol that translates onto the isometric, so a custom component needs a symbol key assigned or the isometric will not plot it. And because the model is dimensionally real, you can check that a valve can actually be reached and operated, or a strainer basket pulled clear, before it becomes a problem on site rather than after.
Tagging follows the same hierarchy as the rest of the model: a component takes its line number and carries a unique reference, which is what lets your valves and instruments come through correctly onto your schedules later in the series.
In line components are the clearest case yet for capturing the real plant, because they change more than almost anything else on site. And here a scan has an honest limit worth being straight about. The laser captures what is physically there, the valve bodies, their sizes and their connection types, but it cannot read a valve’s internal rating or material off the outside of the shell. So for an existing site we model the real components from the point cloud, then gather the data the scan cannot see, from nameplates, records and walkdowns, and attach it. The schedule then reflects the valve actually installed, not the one the original drawing said should be there.
This is our work. For existing sites we model the in line components that are really there from the laser scan, and capture the rating and material data the scan cannot see, so your valve lists and instrument schedules are built on the plant as it stands. We place spec correct components that connect cleanly and carry the right data, tagged to your standard, so the model is ready for isolation, maintenance and reporting, not just to look at.
If your valve and instrument records have drifted from the field, the in line components are exactly where that gap does the most damage. It is worth closing.
Next in this series: The Breakdown of Plant 3D Structural Steel.
