Inspecting a giant aboveground storage tank has traditionally been one of the more miserable and dangerous jobs in the energy business: drain the tank, ventilate it, and send people inside a confined space that recently held volatile hydrocarbons. Houston's Square Robot has spent years replacing that process with autonomous submersible robots — and its newest model can now do it inside tanks hot enough to cook in.
What the SR-3HT Does
The SR-3HT is an autonomous, submersible robot that swims through the product inside a storage tank, mapping the tank floor for corrosion and thinning while the tank stays in service. The headline advance is thermal: it operates across a range of 14°F to 131°F, a big jump from the company's previous envelope of roughly 32°F to 104°F. It gets there using a combination of active and passive cooling that keeps the robot's electronics alive in heat that would otherwise fry them.
Crucially, the SR-3HT earned NEC/CEC Class I Division 2 (C1D2) certification from FM Approvals — meaning it's cleared to operate in hazardous, potentially explosive atmospheres. That certification is what allows on-stream inspection of tanks holding products stored at elevated temperatures, exactly the conditions common in refining and petrochemicals.
Why It Matters
The value proposition is safety and uptime at once. Sending the robot in means no human has to enter a toxic, oxygen-deficient confined space — eliminating one of the highest-risk tasks in the industry. And because the robot inspects the tank on-stream, operators don't have to take the tank out of service, drain it, and clean it just to check its condition. That's a large cost and downtime saving on top of the safety benefit.
The extreme-temperature capability specifically opens up tanks and regions that were previously off-limits to robotic inspection. As the company has noted, elevated process temperatures and hot ambient climates — think the Gulf Coast in August, or the Middle East — frequently pushed conditions beyond older robots' limits. A wider thermal envelope means more of the world's tanks become inspectable without a human entry.
The Houston Connection
Square Robot opened its Houston office in 2019, planting itself in the heart of the world's largest concentration of storage tanks — the Gulf Coast refining and petrochemical complex. That proximity to customers is the same logic that built Houston's subsea-robotics cluster: the hardest inspection problems, and the operators who need them solved, are right here. The company has also moved to scale its fleet through a partnership with Marathon Petroleum, a signal that major operators see robotic tank inspection as a standard tool rather than a novelty.
Square Robot sits alongside a growing set of Houston companies applying robotics to energy-asset inspection — from drone-based methane detection like Aquanta Vision to the broader field on display at the annual Energy Drone & Robotics Summit. The common thread: replacing dangerous, manual inspection work with autonomous machines that do it more safely and more often.
Reporting based on coverage by InnovationMap. Original story: innovationmap.