Slow train coming: load cells and axle weights
This week has seen the biggest shake-up of train timetables in a generation. According to rail operators Govia Thameslink (GTR) :
“It will be running 3,600 trains across its network which includes Southern rail, Gatwick Express, Thameslink and Great Northern – this is 400 additional trains.” The changes would also “Create space for an extra 50,000 morning peak-time passengers travelling into London.”
That’s a lot of extra trains running on the rails, and a lot more weight too in the morning rush hour. Needless to say, load cells will be doing their part to monitor axle weights for safety and a smoother ride to work!
Load cells in train depots
Just like trucks, rail operators need to check for unbalance of wheel loads to ensure the safe operation of the train and a smooth, comfortable ride for passengers.
In a depot workshop, the wheel load is measured using under-rail load cell systems. These are usually set in a pit below track level, with rails set on a weighing base comprising a top section and a bottom section. The load cells are set in between, like the filling in a sandwich.
The train simply rolls over the weighing track, stops whilst the load cells record the data, and then rolls off again. Data can be used from such system to check individual axle loads, bogey loads, or the weight of an entire carriage or locomotive.
Putting the brakes on
Train brakes need to apply an even pressure to each train wheel to ensure it stops safely and efficiently. Load cells can be used to test either disk brakes or block brakes by replacing the actual disk or block and measuring the force applied when the train is static. The data can be relayed wirelessly to a handheld unit to identify any maintenance requirements quickly and easily, and improve operational safety as a result.
Keep ‘em rolling: WIM (weighing in motion) solutions
Weighing in motion solutions are ideal for operators who ned to check weights but don’t want rolling stock holed up in a shed for hours. In an interesting paper, Denis M. Senyanskiy of the Moscow State Aviation Institute describes the particular challenges of getting accurate readings from WIM systems in the challenging environment of the Russian rail network.
“We built a carriage identification algorithm that determines how many carriages are being weighed at the moment. The carriage and locomotive fleet of the railways of The Russian Federation consists of more than 300 carriages and more than 30 locomotives. All of them have different axle arrangements (there are 4-, 6- and 8-axle carriages and locomotives available), different lengths and different carriage- and bogie-bases. This makes identification more complicated.”
Portable Train Weighers
The latest generation of train weighing devices are portable, enabling them to be attached to any existing length of outside track or depot workshop rails. The system consists of adjustable rods which stretch between the tracks, with adjustable entry and exit ramps for the train wheels and their flange.
“The base work lifts the wheel tyre but keeps the flange within the rail head allowing the simultaneous weighing of the wheel flange through a signal from the load cells.”
The beauty of this portable system is that it can be taken to the train, for use on any rail system including trams, metro trains, and on-track plant machinery.
Load cells for trains, planes and automobiles
If you need a load cell system for any transportation use, give us a call. We have a vast range of load cells in stock, and can also deign and manufacture to your specific requirements. Just give us a call to discuss your next project.
