LPG System Suppliers

LPG systems cover the cargo containment, cargo handling, refrigeration, and fuel supply equipment that marine LPG carriers and LPG-fueled vessels rely on. LPG (Liquefied Petroleum Gas) consists primarily of propane (C3H8) and butane (C4H10), stored either fully refrigerated at -42°C or under semi-pressure at 5-7 bar in dedicated cargo tanks. The LPG system suppliers listed on Records Marine cover the OEM and authorised distributor channels for cargo carriers (VLGC, LGC, MGC) and the emerging fleet of LPG-fueled vessels with ME-LGIP propulsion.

The procurement decision spans containment type selection (Type A fully refrigerated, Type C semi-pressure), cargo handling capacity (compressors, deepwell pumps, booster pumps), reliquefaction plant configuration, vapor management arrangements, and the integration with main engine and auxiliary systems. Picking the right LPG system suppliers means matching equipment specification to vessel class, cargo trade pattern, and the IGC Code compliance scope required by class society approval.

What LPG Systems Cover Onboard

Marine LPG systems break across several integrated equipment groups:

• LPG cargo containment - Type A prismatic tanks (fully refrigerated at -42°C), Type B less common on LPG, Type C pressure vessels (semi-pressure 5-20 bar). Tank material typically 9% nickel steel for fully refrigerated or carbon steel for pressure tanks.
• Cargo handling equipment - multi-stage piston cargo compressors, deepwell cargo pumps mounted inside the tank, booster pumps for cargo discharge, manifold and transfer piping.
• Refrigeration and reliquefaction - direct-cycle or cascade reliquefaction plants that re-condense boil-off vapor and maintain cargo temperature during loaded voyage.
• Vapor management - PV valves, vent risers, vapor return manifolds, inert gas dilution for cargo loading and discharge.
• Cargo heaters and conditioning - heating cargo to discharge temperature where receiving terminal requirements call for it.
• LPG fuel supply systems (FSS) - on LPG-fueled vessels with ME-LGIP dual-fuel engines, the fuel supply system handles bunker storage, gas valve unit (GVU), and fuel preparation for combustion.
• Cargo monitoring and gas detection - fixed gas detection in cargo holds, machinery spaces, and crew accommodation gas-safe zones.

The IGC Code (International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk) governs the design and construction standards for all marine LPG equipment.

LPG Cargo Containment Types

LPG cargo containment follows the IGC Code Chapter 4 tank type classification:

• Type A tanks (prismatic, fully refrigerated) - flat-walled or prismatic tanks built into the vessel hull, holding LPG at atmospheric pressure and cargo temperature (-42°C for propane). Requires complete secondary barrier under the IGC Code. Common on Very Large Gas Carriers (VLGC) and Large Gas Carriers (LGC).
• Type B tanks (independent, partial secondary barrier) - less common on LPG carriers but used on some specialised tonnage. Self-supporting with partial secondary barrier.
• Type C tanks (pressure vessels) - cylindrical or bilobe pressure vessels rated 5-20 bar working pressure. Holding LPG semi-pressurised at -10°C to -20°C. Dominant on Medium Gas Carriers (MGC), small LPG carriers, and LPG-fueled vessels storing fuel onboard.
• Pressure tank arrangements on small carriers - some smaller LPG vessels use multiple Type C pressure tanks arranged longitudinally, allowing different cargo grades per tank.

Containment selection drives the entire LPG system architecture - fully refrigerated arrangements require larger reliquefaction capacity but lower tank pressure, while pressure systems eliminate reliquefaction need but require thicker-walled tanks.

LPG Cargo Handling Equipment

The cargo handling system controls loading, voyage maintenance, and discharge operations:

• Cargo compressors - multi-stage piston compressors handle cargo vapor during loading, reliquefaction during voyage, and cargo discharge operations. Burckhardt Compression, Sauer Compressors, Cryostar, and Wartsila Hamworthy dominate the OEM landscape.
• Deepwell cargo pumps - submersible pumps mounted inside the cargo tank with motor on deck driving through a long shaft. Svanehoj (now Alfa Laval), Frank Mohn (Framo), and MAN ES supply the main brands.
• Booster pumps - high-head pumps used at discharge to overcome shore-side pressure requirements.
• Cargo heaters - shell-and-tube or plate heat exchangers used where cargo discharge temperature must be raised (e.g. delivery to non-refrigerated shore tanks).
• Reliquefaction plants - direct-cycle (LPG vapor compressed and condensed) or cascade-cycle (using refrigerant loop) systems that re-condense boil-off vapor. Cargo Care Solutions, Cryostar, and Wartsila Hamworthy supply the major plant designs.

LPG Fuel Systems and ME-LGIP Propulsion

LPG-fueled propulsion is the fastest-growing application for LPG system suppliers outside of traditional cargo carriers. MAN Energy Solutions ME-LGIP (Liquid Gas Injection - Propane) engines run on LPG as primary fuel with diesel pilot, on vessels including LPG carriers themselves (using cargo as fuel) and newbuild ammonia/methanol-ready vessels using LPG as transitional fuel.

The LPG fuel supply system covers:

• LPG fuel tanks - typically Type C pressure vessels sized for voyage duration and engine consumption
• Fuel supply pumps - cryogenic centrifugal pumps delivering LPG to the engine fuel valve train
• Gas Valve Unit (GVU) - the safety isolation and emergency shutdown assembly between fuel storage and engine
• Fuel preparation - vaporiser, pressure regulation, temperature conditioning
• Engine room fuel piping - double-wall piping under IGF Code requirements

Major LPG System Brands and OEMs

The LPG system market concentrates around several major OEM brands:

• Wartsila Hamworthy - cargo handling, reliquefaction plants, gas systems
• Cryostar - cryogenic equipment, compressors, pumps
• TGE Marine - tank engineering and complete LPG cargo system design
• MAN Energy Solutions - ME-LGIP engines and complete LPG fuel supply systems
• Burckhardt Compression - high-pressure piston compressors
• Sauer Compressors - reciprocating cargo compressors
• Svanehoj (Alfa Laval) and Frank Mohn (Framo) - deepwell cargo pumps and booster pumps
• Mitsubishi Heavy Industries - integrated LPG cargo system delivery on Japanese newbuilds
• Kawasaki Heavy Industries - LPG cargo tank and system fabrication
• Cargo Care Solutions - reliquefaction and cargo systems

Choosing an LPG System Supplier

Picking among LPG system suppliers requires matching equipment specification to vessel class, cargo trading pattern, and the IGC Code compliance scope:

• Vessel type and cargo grade match - VLGC and LGC operating fully refrigerated; MGC and small LPG carriers using semi-pressure Type C; LPG-fueled vessels carrying LPG as fuel storage only. Each scope drives different containment and handling architecture.
• IGC Code compliance documentation - the supplier must provide Material Type Approval certificates, Tank Type Approval, and Class society approval (DNV, ABS, Lloyd's Register, Bureau Veritas, RINA, ClassNK, KR, CCS).
• Containment system manufacturer authorisation - Type C pressure vessel manufacturers carry their own approval scope; the supplier should clarify whether they manufacture, integrate, or distribute the containment system.
• Cargo handling capacity match - compressor and pump sizing matched to cargo loading rate, voyage duration, and discharge rate requirements.
• Spare parts and lifecycle support - LPG cargo systems run for the vessel's full service life (25+ years); supplier should have authorised LPG system spare parts support across the operational years.
• Service network presence - cargo handling equipment requires periodic overhaul; supplier should have service capability at major LPG hubs (Houston, Ras Tanura, Mongstad, Yanbu, Singapore).

Need LNG containment systems (membrane, Moss, IHI SPB) or cryogenic handling equipment instead? See LNG system suppliers for that distinct technical scope.

Frequently Asked Questions

What is the difference between LPG and LNG systems?

LPG (Liquefied Petroleum Gas) is propane and butane stored at -42°C fully refrigerated or under semi-pressure 5-20 bar. LNG (Liquefied Natural Gas) is methane stored at -162°C cryogenic at atmospheric pressure. The containment systems are completely different - LPG uses Type A prismatic or Type C pressure tanks with mid-level insulation, while LNG uses membrane (GTT), Moss spherical, IHI SPB, or Type C cryogenic tanks with heavy vacuum or polyurethane insulation. The handling equipment, brand landscape, and regulatory scope differ accordingly.

What types of LPG carriers exist?

LPG carriers split by size: VLGC (Very Large Gas Carrier) 80,000-90,000 m³ fully refrigerated; LGC (Large Gas Carrier) 30,000-80,000 m³ fully refrigerated; MGC (Medium Gas Carrier) 15,000-30,000 m³ semi-pressure or fully refrigerated; SR (Semi-Refrigerated) 5,000-15,000 m³ semi-pressure; FP (Fully Pressurised) small coastal LPG carriers under 5,000 m³ using Type C pressure tanks at ambient temperature.

What is ME-LGIP propulsion?

ME-LGIP (Man-B&W ME-engine with Liquid Gas Injection - Propane) is MAN Energy Solutions' dual-fuel 2-stroke engine running on LPG as primary fuel with marine diesel pilot. The engine uses high-pressure direct injection of LPG into the combustion chamber. Common on newbuild LPG carriers using cargo as fuel, and on multi-fuel vessels using LPG as a transitional low-carbon option. The companion ME-LGIM engine runs on methanol; ME-GI runs on LNG.

What containment systems does LPG use?

LPG containment under IGC Code Chapter 4 uses three tank types: Type A prismatic tanks (flat-walled, fully refrigerated at -42°C, requiring complete secondary barrier) on VLGC and LGC carriers; Type C pressure vessels (cylindrical or bilobe, rated 5-20 bar, semi-pressure at -10 to -20°C) on MGC, small LPG carriers, and LPG fuel storage onboard LPG-fueled vessels; Type B tanks less common on LPG carriers but used on some specialised tonnage. The containment choice drives reliquefaction capacity, insulation design, and overall LPG system architecture.