The Niigata HX Series represents a complete lineup of modern, medium-speed diesel engines designed for marine and industrial applications. These 4-stroke engines feature a best design with a highly rigid monoblock cylinder block, integrating lubrication and cooling passages for compactness and reliability. Known for their fuel efficiency, HX engines incorporate advanced technologies like non-cooled turbochargers and direct-mounted air coolers to optimize performance.
Their simplified maintenance design, including easily removable cylinder units, makes them a practical choice for vessel operators seeking durability and operational cost savings.The Niigata HX Series is a range of medium-speed 4-stroke diesel engines developed for modern shipbuilding requirements. Designed for reliability, fuel efficiency, and long service life, these engines are suitable for a wide variety of commercial and industrial marine applications, including tugs, ferries, offshore support vessels, cargo vessels, and workboats.
As an OEM-authorised partner, Neptunus supports shipyards, vessel owners, and marine consultants with engine selection, project planning, technical coordination, commissioning support, and genuine Niigata solutions throughout the vessel lifecycle.| Parameter | HX Series | Remarks |
|---|---|---|
| Models | 6MG19HX, 6MG22HX, 6MG25HX, 6MG28HX, 8MG28HX, 6MG34HX, 8MG34HX, 6MG41HX | Configurations: Inline 6–16 cylinders |
| Bore × Stroke (mm) | 190×260 – 410×550 | Larger bore = higher power |
| Displacement (L/cyl) | 9.29L–11.63L | 6MG41HX: Largest displacement |
| Dry Weight (tons) | 7.0–64.0 | 6MG41HX: Heaviest (64 tons) |
| Compression Ratio | 16:1 | Optimized for Marine Diesel Oil (ISO 8217) |
| Aspiration | Turbocharged (ABB TPS) | High-efficiency turbocharger |
| Parameter | HX Series | Remarks |
|---|---|---|
| Max Power (kW/PS) | 761–5,890 kW / 1,035–8,810 PS | 6MG41HX: Highest power (5,890 kW) |
| RPM Range | 520–1,650 RPM | 6MG25HX/28HX: 750 RPM (high torque) |
| BMEP (Bar) | 10–12 | High BMEP = improved efficiency |
| Fuel Consumption (g/kWh) | 195–210 | Competitive for medium-speed engines |
| Emissions Compliance | Tier II (SCR-ready for Tier III) | Meets IMO NOx regulations |
| Parameter | HX Series | Remarks |
|---|---|---|
| Cylinder Block | Monoblock nodular cast iron | Integrated cooling pipes, high rigidity |
| Turbocharger | ABB TPS (non-cooled) | Corrosion-resistant, high-pressure ratio |
| Fuel Injection | Mechanical | Reliable, low maintenance |
| Cooling System | Jacket water + air | Air cooler directly mounted on block |
| Gauge Board | “Grafico” digital display | LED bar graphs for real-time monitoring |
| Parameter | HX Series | Remarks |
|---|---|---|
| Overhaul Interval (hrs) | 8,000–10,000 | Dependable for long-term use |
| Key Wear Parts | Liners, pistons, bearings | Replaceable cylinder liners |
| Lube Oil Interval | 700 hrs | Standard maintenance cycle |
| Parameter | HX Series | Remarks |
|---|---|---|
| Best Suited Vessels | Offshore supply vessels, Tugs, Ferries, General cargo ships | Versatile for medium power needs |
| Installation Flexibility | Compact V-design | Fits tight engine rooms |
| Noise/Vibration | Moderate (dampened) | Balanced for crew comfort |
As an OEM-authorised Niigata partner, Neptunus provides comprehensive lifecycle support for Niigata marine engines, from new engine supply for shipbuilding projects to commissioning, maintenance, overhaul, and genuine spare parts support. Backed by over 30 years of industry experience and more than two decades of expertise with Niigata engines, we help shipyards, vessel owners, and operators maximise engine performance and operational reliability throughout the engine’s service life.
Our capabilities begin with the supply of new Niigata marine engines for newbuild vessels, including technical consultation, installation guidance, and commissioning support to ensure seamless integration and optimal performance from day one. Throughout the operational lifecycle, we deliver expert repair, maintenance, and overhaul services designed to minimise downtime, extend engine life, and maintain peak efficiency.
To support long-term reliability, Neptunus also offers a comprehensive range of genuine Niigata spare parts, ensuring full compliance with OEM specifications and performance standards. By combining technical expertise, responsive service, and authentic components, we provide end-to-end solutions that support safe, efficient, and sustainable vessel operations.Fill in Details for a Quote
