8S70ME-LGIM9.6

Designation decoded

{'engine_builder': 'MAN Energy Solutions', 'type_designation': '8S70ME-LGIM9.6', 'fuel_type': 'Methanol (Liquid Gas Injection, Methanol)', 'mark_version': '9.6', 'cylinder_count': 8, 'bore_mm': 700, 'stroke_mm': 2800, 'stroke_type': 'Super-Long-Stroke (S)', 'operating_principle': 'Two-stroke crosshead engine with direct methanol injection', 'configuration': 'In-line engine, 8 cylinders'}

Background

The 8S70ME-LGIM9.6 is a Super-Long-Stroke two-stroke crosshead engine with direct methanol injection at 600–700 bar injection pressure. LGIM technology enables operation with methanol as the main fuel with simultaneous pilot injection of VLSFO/MGO. The 8-cylinder design offers the most favourable mass-balance ratios and the lowest free inertial forces and moments. The S70 series is suitable for medium-sized container ships, tankers and bulk carriers. Methanol has a flash point of only 12 °C, is toxic and attacks conventional sealing materials. BN25 cylinder oil lubrication is required to counter cold-corrosion risks from the combustion products.

Calculated metrics

Inspector checklist

Logbook reference values

Common Failure Modes

Expert tips

• 💡 Always purge all methanol-carrying connections with inert gas after maintenance work and perform a leak test before returning to service – methanol vapours are invisible and toxic (occupational exposure limit 200 ppm)
• 💡 During cylinder liner inspections, pay particular attention to the area below the scavenge ports – the absence of sulfur passivation in methanol operation fundamentally changes the wear pattern compared with HFO operation
• 💡 Regularly perform scrape-down analyses of the cylinder oil to monitor BN consumption and corrosion indicators

Related components

Classification & regulatory

Methanol as a marine fuel is subject to the IGF Code (International Code of Safety for Ships using Gases or other Low-flashpoint Fuels). Classification-society-specific additional requirements must be observed (e.g. DNV Rules for Classification, Part 6 Chapter 2 Section 5). Flag state approvals and special permits for low-flashpoint fuels (flash point 12 °C) must be obtained before entry into service. SOLAS II-2 fire protection requirements apply in extended form.