Understanding Rail Scales

Vintage railroadPurpose of Rail Scales
Rail scales, as you might guess, are scales installed in train rails to measure the weight of train cars as they travel. Scales can measure if the cars are too heavy and could be dangerous or if the weight has changed throughout the journey. Monitoring the weight of train cars while they travel is critical for the safety of passengers and the cargo. It will also ensure that nothing is added or removed without the train engineer’s knowledge.
These scales can also monitor the behavior of cargo as the train makes its way toward its destination. If a train car holds cargo such as liquid or gas, weighing the car periodically will help see if temperature changes affect the cargo and how to preserve the freight as much as possible.  These scales are also used to insure that the railroad cars aren’t overloaded so as to not damage the rails and become a safety hazard to the public.
How Rail Scales Work
The rail scales are installed with the train tracks and measure several different weights. First the entire car weight is measured and then the “tare weight” or the weight of an empty car is applied and you are able to get the total weight of the freight within the train car. From there you can compare with other data acquired throughout the journey to ensure that the freight and passengers are safe and everything is accounted for.
There are also portable rail scales that you can temporarily install on rails to measure weight and collect data. To install these you must measure the distance between tracks and have the proper amount of shims (washer-like parts to prevent damage) to the rail keys, which will attach the scales to the rails. The scales must be attached to the rails securely and flat so the car can move over them effortlessly. The cables are connected to the rail scales and to the reader so you can measure the weight and collect the data. The cables must be protected so they are not damaged or severed as the train passes.
How Rail Scales Are Used
These scales are used everyday throughout the railroad industry for everything from livestock to grain to industrial parts. Rail scales are incredibly important to ensure the cargo gets to its destination safely and intact. Though many think of railroads as being not as popular as they once were, it’s evident from the tracks all around us that  railroads are still used to move freight and passengers all over the country and are necessary to support our culture and way of life.