Global rail maintenance leader LORAM explains what rail grinding is, why we need to do it – and how its machines and technologies are ahead of the curve.

When people think about rail grinding, they might picture a huge machine rolling down the tracks at night, throwing out a shower of sparks.

It looks dramatic, but what is actually happening when a rail grinder is at work? Why do we even need to grind rail?

We spoke to the team at railroad maintenance equipment and services provider LORAM to find out the answers to these questions and more.

Why do we need to grind rail?

In 2000, a train derailed between Welham Green and Hatfield in the United Kingdom, killing four people and injuring over 70.

Investigators found the cause of the derailment was a fracture in the rail, which was due to the presence of multiple pre-existing fatigue cracks.

The report published by the Office of Rail Regulation said these cracks were the result of a failure to effectively manage the inspection and maintenance of the rail at the site of the accident.

“They hadn’t been keeping up with their maintenance and inspection regime, of which grinding is a key part for managing Rolling Contract Fatigue or RCF,” said Nigel Slater, Head of Business Development at LORAM. “This tells you that from a rail health perspective, grinding is a critical process. If you don’t do it, your rail will fail.”

Grinding rail is critical not just for safety reasons, but it also makes economic sense.

“Without an effective grinding strategy, some operators are seeing rail require replacement much earlier than expected,” said Slater.

“Putting new rail in is very expensive, you really want to avoid that situation.

“You might think you’re saving money by not performing critical maintenance like grinding, but it is a false economy.”

What does grinding actually do?

In simple terms, rail grinding is about controlling the shape and condition of the railhead – the top surface and profile of the rail that the train wheels run along.

“Rail gets degraded by trains running over it,” explained Slater. “Different rail networks place different types of stress on the rail. Heavy haul operations, like the mining railways in the Pilbara, create very different wear patterns to metro systems, where high-frequency passenger services generate their own unique demands on the track.

“Over time, trains will start to harden the head of the rail and can denature it from when it was first made.”

LORAM’s job as a grinder is to maintain or restore the profile of the rail to ensure trains travel safely and comfortably over the tracks and extend the life of the rail.

Grinding is far from guesswork – Slater said LORAM considers itself a physics-based company at heart.

“We’re dealing with the physics of a certain shape or rail profile, a wheel profile and tonnage, in a particular operating environment, on a certain type of steel, reacting dynamically over time.

“You need to have a different approach for low rail and high rail, on tight curves and longer curves.”

The sweet spot

Slater said that with heavy trains rolling over the rails, Rolling Contact Fatigue starts to occur.

This results in cracks and defects that can develop into larger cracks if not addressed, potentially leading to fractures in the rail.

“LORAM’s systems and people will recognise when these defects start to appear, and that’s when we’ve got to take a different approach,” said Slater.

“At that stage, it’s not about just maintaining rail profile, it’s about removing early defects or managing those defects if they are significant enough that they can’t be removed.”

He said having a defect that can’t be removed isn’t a bad thing – it just means that you need a process or program to manage it.

“You’ll need to decide whether you remove the defect, which means you are taking metal off the rail,” he said.

“The best solution is for us to take off just enough metal that the defect doesn’t get worse, but not so much that we are artificially shortening the life of the rail.

“It’s a fine balancing act – and our systems and experience allow us to hit the sweet spot.”

Precision and productivity

LORAM’s rail grinders combine high power, flexible grinding modules and unique control systems to deliver industry-leading precision and productivity.

With 30-horsepower motors, they can apply more grind power, allowing them to complete work faster.

“This is of huge value to the customer, because the faster we can get a good job done, the faster we can get our machines off the tracks and out of their way,” Slater highlighted.

“We always strive to hit the gold standard of completing quality grinding, both quickly and safely.”

The global maintenance provider also prides itself on the reliability of its machines.

“If your machines are constantly breaking down, the customer is not going to be happy.

“When they have coal trains, passenger trains or iron ore trains, for example, that aren’t able to run, that’s costing them a lot of money and frustration.

“We have 250 grinding machines worldwide, with machine reliability above 98 per cent.”

This reliability is supported by continuous improvement to the machines, drawing on the combined expertise of teams around the world.

Slater pointed out: “We’ve run our machines in basically every different type of environment on the planet.

“The learnings we get from doing that become a really important part of our tribal knowledge, which is then fed back into our engineering and manufacturing processes.”

LORAM’s rail grinders also boast adjustable grindstones for the highest precision.

“Each grinding machine could have a range of grindstones between eight and 120, based on how large the machine is.

“We can individually control the grindstones and use different grit sizes from fine to medium and large, depending on how much metal needs to be removed and the finish required.

“We can also align the grindstones to get better coverage over the rail head.”

LORAM’s operators also have many years of experience, which have given them a deep understanding of effective grinding.

“Our team has been doing this for so long, they’ve almost got a sixth sense about the best approach or when something is wrong.

“That human element is really important.”

Where technology comes in

Slater said LORAM is at the forefront of rail technology with tools such as Virtual Rail, which helps track engineering teams to decide on the best maintenance strategies to extend track life, find and prevent defects, and save money.

Using data from a customer’s network, as well as from LORAM’s machines, it can create a virtual twin.

“This then creates an economic model, looking years into the future,” said Slater.

“That way, rather than having a short-term approach to maintenance, we can help our customer to develop a plan to extend the life of their rail for 15 to 25 more years.”

Currently, LORAM uses a rail inspection vehicle (RIV) equipped with lasers, cameras and other sensors to measure rail profiles, detect and classify defects, and capture images and other data. This information is then communicated to the grinding crew.

Slater said the RIV currently plays a critical role in collecting the detailed data needed to plan and optimise grinding activities, while new technologies are creating opportunities to capture and analyse rail condition data in different ways.

LORAM recently partnered with British company One Big Circle, the creators of Automated Intelligent Video Review (AIVR) technology.

AIVR uses automated data capture, intelligent analysis, and streamlined reporting to enable engineers to detect issues faster, improve safety and maintain the reliability of rail networks.

AIVR has cameras, including thermal imaging, that go on the front of the train and under the locomotive and take high-definition, high-speed images of the rail line, the sleepers, and vegetation around the tracks. Engineers can click on any section of track and instantly see images, measurements, and historical changes.

“Using artificial intelligence, AIVR monitors the network over time and alerts teams when something moves, bends, or degrades, rather than relying on people to go out all the time and physically inspect the track,” explained Slater.

“That’s going to be a game changer for us and our customers as it means safer operations, better visibility of the network, and more informed maintenance planning.”

“This is where LORAM rail maintenance is heading: smarter, more connected, and increasingly predictive.”