
HMT Tank Systems BV
About us
Since our founding in 1978, HMT has been a leader in aboveground storage tank technology and environmental solutions for the energy industry. Our global team partners with customers to solve complex storage challenges, helping reduce emissions, optimize tank capacity, recover stranded inventory, improve safety, reduce downtime, and extend maintenance intervals.
HMT offers a comprehensive portfolio of products, including internal and external seal systems, floating suction and drain systems, aluminum dome and floating roofs, seamless composite roofs, and emissions reduction devices. Our design, construction, maintenance, inspection, and repair services help optimize tank safety, efficiency, and performance.
We operate across the globe, serving industries including oil and gas, chemical, petrochemical, pipelines, refining, terminals, mining, water and wastewater, food processing, and renewables.
Products & services

ALUMINUM GEODESIC DOME ROOF
The HMT Aluminum Dome features a clear-span, all-aluminum, lightweight, corrosion-resistant structure which sets a new standard for performance in aluminum domes. HMT’s unique clamped-panel design and attention to detail at critical locations result in a cost-effective solution that provides superior protection of your stored product.

ALLENTECH HC FULL CONTACT FLOATING ROOF
The Allentech HC Full Contact IFR is a premium Honeycomb Full Contact Aluminum IFR. The Allentech HC is designed in accordance to API650 and EN14015 with a minimum buoyancy ratio of 2x against the roof dead load plus friction force exerted by perimeter seals using a drag coefficient of no less than 3 lbs/ft. The roof is capable of staying afloat while having two adjacent flotation compartments flooded. The roof buoyancy is based on a Specific Gravity of 0.7 or the stored product, whichever is less. The panel modules are 5ft x 10ft x 1.5in deep (1524mm x 3048mm x 38.1mm). Rim modules are designed to match the tank shell radius. Each sandwich-module consists of a top and bottom layer of .050in aluminum sheet with an internal honeycomb structure to provide stiffness. A high quality aluminum extrusion forms a frame around the sheet and honeycomb, and this is completely seal welded into a fully enclosed buoyant compartment. Each module contains a resealable vapor detection port for pressure testing in our factory, and also for future testing during out-of-service maintenance. Damaged panels that are installed can be easily replaced during future maintenance. Every module is fully inspected and pressure tested with helium leak detection equipment prior to shipment. The Hook and Pin design of the modules allows for quick installation and forms an high strength bolted seam with extremely low seam emission losses.

DECKMASTER GRP FLOATING ROOF
The Deckmaster GRP Advanced Composite Floating Roof is a seamless, nonmetallic full-contact floating roof. Its gastight polypropylene honeycomb core is “sandwiched” between multiple layers of fiberglass utilizing modern high-grade vinyl ester resins designed to be resistant to most hydrocarbons. The result is a smooth, seamless, and virtually indestructible full-contact floating roof that is also corrosion free, thus necessitating little or no maintenance. The Deckmaster remains in full contact with the stored product, preventing evaporative losses. The low-profile cross section of the roof maximizes the storage capacity of the tank. Designed to accommodate both a mechanical shoe primary seal and a secondary seal, the Deckmaster is fully gastight, leak proof, and virtually unsinkable. The robust design also enables it to withstand operational stresses such as pigging and butter washing. From diameters as large as a football stadium to large-scale external floating roof applications, this technology represents the absolute premium in floating roof performance with best-in-class emissions, corrosion resistance, ability to handle dynamic loads, buoyancy ratio, walkability, and longevity.

SEALMASTER® PRIMARY & SECONDARY
The Sealmaster floating roof seal system was developed over 35 years ago, with the goal of making a seal that adjusts to the irregularities of tanks while remaining gas-tight and virtually maintenance-free. The solution is the Sealmaster seal system. The Sealmaster is comprised of fully hardened compression plates, extending from the floating roof rim to the tank shell and down into the stored product, thereby providing a non-combustible protective sheath over a fully-heat-welded vapor barrier encapsulating the entire vapor space.

SEAL KING SECONDARY SEAL
Low-Profile Secondary Seal The Seal King low-profile secondary seal was specifically designed to give storage tank owners the ability to maximize tank working capacity. With its extremely low profile, the Seal King increases the working capacity of a floating roof tank, allowing tank owners to increase competitiveness and profitability. The Seal King also has unsurpassed vapor-sealing ability and exceptional water-shedding capability.

FLEX-A-SEAL
Rim-mounted Compression Plate Type Wiper Seal The HMT Flex-A-Seal Secondary Seal is one of the most economical and effective types of secondary seals available. Easily installed and maintained, the HMT Flex-A-Seal’s ability to meet or exceed stringent gap specifications for secondary seals has earned its approval from governmental regulatory agencies throughout the U.S. and European markets.

FOAMDAM STAINLESS STEEL
Foamdam Stainless Steel compliant NFPA 11 2024 Edition

GUIDE POLE SLEEVE SEAL
The Enviro-Sleeve Gauge Pole Seal was designed as a zero-emissions, reliable, durable, and maintenance-free guide pole sleeve that has the capability to be retrofitted without any modifications to the EFR. For a vapor-tight guide pole sleeve that can be installed easily, quickly, and as a custom-fit solution with no maintenance, while lasting the life of your tank, choose the Enviro-Sleeve.

PIVOT MASTER® Floating Roof Drain System

SUMPMASTER SUMP VALVES
The SumpMaster is a sturdy sump valve designed to prevent product flow onto external floating roofs from drain system failures. The SumpMaster addresses several problems with traditional check valves, including more effective sealing at the potentially lower pressures encountered during a drain system failure, and not restricting drain flow rates calculated during the design of the floating roof.

GASDIFFUSOR
Gasdiffusors FEM analyzed to your operational window

ENDURANCE SS FC INTERNAL FLOATING ROOF
HMT’s ENDURANCE stainless steel full contact heavy duty internal floating roof was developed in response to market demand for a high quality, durable, corrosion resistant full contact IFR’s for demanding conditions that can readily accommodate a liquid mounted gas tight compression plate seal. The HMT ENDURANCE is fully compliant with API 650 Appendix H and the EN 14015. A pinnacle of durability, corrosion resistance, and unmatched performance for storage tanks., choose the HMT ENDURANCE full contact IFR.
Job ads

Project Manager at HMT
Join our team as a Project Manager at HMT! Based in the Netherlands, you'll be the key link between HMT and our customers, driving successful project planning and execution. In this vital role, you'll oversee project coordination, ensuring goals are met on time and within budget. As the central point of contact, you'll manage all technical and commercial aspects of the project, ensuring seamless communication and smooth operations. Your leadership will make a real impact – are you ready to lead the way?

Technical Advisor at HMT
Are you excited about joining a highly diverse international team and the prospect of contributing to an industry-leader in emissions-mitigation equipment for aboveground storage tanks? We will be excited to receive your CV and motivation letter. About HMT HMT is the world leader in emissions-mitigation equipment for aboveground storage tanks. Our agile team enables owners and operators to help them meet a full range of storage and environmental challenges, including emissions reduction, tank capacity optimization, and inventory utilization. We engineer tank systems that exceed safety standards, reduce downtime, extend maintenance intervals and, most importantly, protect the environment.