How to Weigh Resin Coming Off a Railcar (and Why It Matters for Your Bottom Line)

When you unload a railcar or truck of resin into your silos, it is easy to assume the amount on the invoice matches what you actually received. The reality is that even small discrepancies can cost your plant a lot of money over the course of a year.

That is why many processors are now installing inline weighing systems with gravimetric hoppers, load cells, and rotary airlocks. These systems give you a straightforward way to check every load before it goes into storage, so you know you are paying for the right amount of material.

How a Railcar Weighing System Works

The concept is simple. Resin is conveyed from the railcar or truck into your silo through either vacuum conveyance or pressure conveyance. By placing gravimetric hoppers on load cells in the line, you can weigh the material as it flows through. A rotary airlock ensures consistent discharge, and depending on your setup, the hoppers tie into either a vacuum pump or a pressure pump.

To size the system correctly, we only need 5 pieces of information:

Whether you use vacuum or pressure conveying
The bulk density of your material
Your flow rate in pounds per hour
Existing conveyance distance from railcar to silo (feet)
Conveying line diameter (inches)

With those details, the rest is straightforward.

Rendering of a railcar unload system from Advanced Blending Solutions (ABS).

The ROI is Too Good to Ignore

Let’s put numbers on it. A typical railcar of polypropylene holds about 180,000 pounds. At $0.75 per pound, that shipment is worth $135,000.

Now imagine the weight is off by just 1 percent. That is 1,800 pounds of material, or $1,350, that you are paying for but not receiving. If you unload 30 railcars a year, that is more than $40,000 lost annually.

What if the error is 2 percent? That is $2,700 on a single railcar, or over $80,000 per year.

The payback on a railcar unload weighing system is often measured in months. In some cases, just catching one short load can cover the entire investment.

And this is not limited to plastics. Powders, chemicals, food ingredients, or any other high-value bulk material delivered by rail or truck can benefit. If it flows into a silo, it can be verified.

A set of Mobihoppers from Advanced Blending Solutions (ABS). These hoppers are outfitted with load cells and integrated into a railcar-to-silo pressure conveying system.

Protect Your Plant and Keep Suppliers Honest

Most resin suppliers do their best, but paperwork errors and loading mistakes happen. By weighing every railcar unload, you have proof of what you received. That protects your margins and strengthens your position in procurement discussions. It also removes uncertainty, giving your team confidence that the numbers in your system are accurate.

Gauge Advisor & Advanced Blending Solutions: We have the Answer

Advanced Blending Solutions (ABS) builds gravimetric hoppers, load cell systems, and material handling equipment in Michigan. Their team understands the unique requirements of plastics plants and has proven solutions for railcar weighing.

Gauge Advisor works directly with ABS and can help you set up the right system. To get started, all we need to know is your convey setup, the bulk density of your material, and your flow rate. Want an in-person audit? We’re happy to arrange an on-site visit!

Advanced Blending Solutions (ABS) is a Michigan-based designer of material handling, blending, desiccant drying, and controls for the plastics industry.

Ready to Verify Every Pound?

If resin or other bulk raw material is one of your largest expenses, this is one of the fastest ROI projects you can take on. The numbers speak for themselves.

Contact us today and let’s review your unloading setup. Gauge Advisor will work with ABS to put together an estimate and show you how quickly this system will pay for itself.