Factory-Built Substation Shipping Logistics

"The line between disorder and order lies in logistics." – Sun Tzu, philosopher

Factory-built substations (FBS) can save significant time and cost. One of our recent FBS projects reduced total construction time by two to three months and generated an estimated $60,000 to $80,000 in construction labor savings. Multiple steps can happen simultaneously, and prefabrication enables components to show up onsite nearly complete.

But that last bit can be easier said than done. The shipping logistics of transporting an entire pre-assembled substation can impose new (and daunting) considerations and obstacles.

For example, our largest ever FBS project had to traverse small roads and winding hills on its trip from Louisiana to Virginia; at one point, it required external assistance just to make some of the tight turns. For another project, clearances were an issue: the truck driver hit a tree and a section of transfer bus broke.

And we always have to consider how to mount the substations to ship them at all. Since every FBS is at least somewhat different, there’s no one-size-fits-all answer to that question. Further, shipments over certain sizes can require special permits, escorts and sometimes limited travel hours. Altogether, such issues can significantly affect shipping costs.

To create as seamless and cost-efficient a shipping experience as possible, logistics must be planned with painstaking detail – and flexibility is a must.

Practices that help with FBS projects include:

  • Begin with the end in mind. “Since nearly anything is possible from a design perspective,” says Frank Camus, Vice President of Engineering and Design for DIS-TRAN, “it is really important for us to determine what the customer places the most value on. There are trade-offs, and we must balance the impact on transportation cost of shipping larger modules with the field cost impact of shipping smaller   modules.” As a result, it’s standard operating procedure at DIS-TRAN to establish logistical requirements before design begins, as much as possible, and then present the customer with multiple options.
  • Communication is key to balance customer needs and shipping requirements. Shipping requirements and restrictions play a large component in the design process of a FBS. “I stayed in constant communication with the trucking company throughout the design phase of the project,” explains David Perry, a Project Manager for DIS-TRAN. This communication is crucial when ensuring a large pre-assembled substation will be able to ship safely, and legally. Each new engineering and design drawing needs to be sent over to the transporter for review. Trucking companies will then let project managers know, based on the design, if the substation is able to fit on the truck safely and what type of permits are required. “As you ship something this big across different states, everything changes,” explains Perry. For example, the state of Louisiana has a shipping height limit of 13’6”. Some states also require special shipping permits. Watch the video below to hear more from David Perry and how he manages shipping logistics for Factory-Built Substation projects.
  • Ship low. Shipping with low boys helps both to keep the center of gravity low and also to ensure that assemblies can fit within available clearances on the road, e.g. under bridges, street lights and other obstacles. On the project that hit a tree (mentioned above), the project manager David Perry had requested four low-boy trucks, but the trucking company was only able to provide three – the fourth truck ended up being a step deck. “If we had the four low boys, we wouldn’t have had a problem,” he says.
  • Understand the route itself as closely as possible. Awareness of road conditions and clearances can stave off problems before they occur. If we realize the trucks will face special considerations on a given route – like those twisty lanes on the road to Virginia – we can better account for them when mounting assemblies to trucks. It’s equally important to understand legal restrictions, e.g. when and where police escorts might be required or travel hours might be restricted.