When it comes to heavy-duty applications such as keeping industrial-grade generators running north of the Arctic Circle or mining for copper 15,000 feet above sea level, reliability isn’t optional—it’s the core of customer trust.
At L&M Radiator, the manufacturer of genuine MESABI® radiators, testing isn’t just a box to check. It’s a culture, a discipline, and a science honed over decades. It’s this commitment to going beyond industry standards that has made MESABI® synonymous with durability around the globe.
In-House Rubber Seal Development and Testing
While L&M did not invent the concept of individually removable tubes mounted in rubber seals, we perfected it. Thousands of testing hours have gone into continually improving the design of MESABI® tubes and rubber seals. This perfected design gives genuine MESABI® heat exchangers an advantage.
A large part of the reason MESABI® rubber seals are so inimitably reliable is because of the vigorous testing they undergo before ever leaving an L&M plant.
Decades ago, L&M learned that relying on standard rubber industry tests wasn’t enough. While most suppliers run tests for 70 to 168 hours (just a few days to a week), L&M runs its own seal testing for a full year—8,760 hours—at extreme conditions.
L&M tests seals for compatibility against a wide variety of oils and coolants and performs other life cycle tests at temperatures ranging from -50°F to 450°F. This helps ensure that machines that work 24 hours, seven days a week in the most frigid and the most scorching parts of the world still run effectively with minimal downtime.
“More than nine million rubber seals per year move through our headquarters facility,” said L&M R&D Engineer Chuck Cedar. “We test the material and physically inspect parts from each shipment before it can reach the customer, ensuring the quality is up to our standards. No one else does that. That’s the level of care we have for our product.”
All tests are completed in-house in a dedicated seal testing lab staffed by full-time employees, and equipped with industry-grade ovens, hardness measurement tools, and precision balances.
The payoff? Problems that most manufacturers wouldn’t discover until equipment failed in the field are identified long before a product leaves Hibbing.
Wind Tunnel Testing: Precision in Motion
While rubber seals are one cornerstone, testing overall airflow and heat transfer is another. Since 1976, L&M has operated its own wind tunnel system, designed and built by the engineering team at L&M Radiator. For context, this is a piece of equipment normally only found at major research universities.
“Most companies rely on theoretical testing information out of a textbook, which is a good place to start, but we take it to the next level,” said L&M Applications Engineering Manager Chris Domogalla.
The wind tunnel allows the company to test radiators under controlled, repeatable conditions and generate precise data on airflow, coolant flow, and heat transfer.
The wind tunnel system has been continually upgraded with modern sensors, frequency drives, and high-accuracy data acquisition tools, ensuring measurements are reliable down to fractions of a degree. Tests can take five to six weeks per core series, with a full-time technician running dozens of coolant and airflow variations to create detailed performance curves.
Engineers also incorporate real-world data they’ve gathered in the field to these curves–a practice that’s won them the reputation of the highest caliber engineers and testing in all of the heavy duty heat exchange industry.
“We are continually trying to achieve the highest accuracy and precision measurements,” said Cedar. “To do that, we use the best equipment available on the market and calibrate on a regular basis.”
Field Testing: Putting it to the Toughest Test of All, the Real World
Lab testing is only half the story. L&M sends engineers into the field—often remote mines, construction sites, and extreme climates—to validate radiator performance under real conditions. According to Domogalla, these “cooling audits” can take up to a week and involve the installation of 60 or more temperature probes on a single machine. Equipment is pushed to its maximum capacity, sometimes even beyond, to ensure performance margins are met.
This practice is part of the reason why Original Equipment Manufacturers (OEMs) trust L&M not only to supply heat exchangers but to lead in testing expertise. In fact, L&M’s testing methods have become so respected that OEMs often adopt them as benchmarks in their own facilities.
This reputation originated in the aftermarket. Early in its history, MESABI® solved reliability problems for equipment owners who were frustrated with conventional radiators. Eventually, customers began insisting that OEMs offer MESABI® as the factory-installed option—a demand strong enough to change industry standards.
“In many cases, the OEM doesn’t know where in the world any given piece of equipment will end up,” said Domogalla. “With field testing, we are able to see what kind of pressure equipment is put under in the real world, then take that data and replicate it in our cooling software for future predictive modeling.”
These field tests aren’t limited to new designs. L&M deploys engineers worldwide—North America, Europe, Australia, Africa—to conduct tests that contribute to L&M’s knowledge base. This closed loop of lab testing and field testing equips L&M with an unmatched understanding of both customer needs over the full lifecycle of a radiator and ensures that MESABI® radiators keep evolving to meet tougher demands.
Raising the Standard
In an industry where many rely on short-term tests, generic materials, or theoretical models, L&M Radiator stands apart. From the meticulous testing of rubber seals, to the high-precision wind tunnel, to boots-on-the-ground audits in mines and deserts, every step reflects a commitment to reliability. It’s why MESABI® radiators have become the trusted choice in environments where failure isn’t an option.
As Cedar summed up: “Nobody cares about your quality more than you do.” At L&M Radiator, a Wabtec company, that belief has built not just a product, but a reputation—built one test at a time.
The MESABI® Difference: Always Raising the Bar
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