What is ship to ship transfer of LNG?

Quick summary:

• Ship‑to‑ship (STS) LNG transfer is the cargo exchange between two LNG carriers side by side.
• Pneumatic fenders act like soft air cushions. They absorb energy and keep the ships apart without hard impacts.
• NANHAI, as a marine fender maker, delivers ISO‑compliant pneumatic fenders, customized sizes, and fast support—so your STS operations stay safe, smooth, and reliable.

1. Why Ship‑to‑Ship LNG Transfer Matters

LNG demand is rising fast. Many ports lack LNG terminals, and carriers must transfer cargo at sea or in anchorages. In these cases, two LNG ships meet and exchange liquefied gas. This method saves time, avoids congested terminals, and helps vessels finish faster missions.

STS LNG transfer has become a widely accepted method for flexible gas delivery, especially offshore or during emergencies.

2. What Exactly Is LNG STS?

Railroads have engines and cars. LNG STS has a mother ship (that delivers the LNG) and a daughter ship (that receives it). The two come side by side—either anchored or slowly moving—and run hoses across to transfer LNG.

Cargo flows in a controlled flow rate. Transfers happen under the guidance of trained crew and a Person in Overall Advisory Control (POAC). They follow guidelines from OCIMF, SIGTTO, SOLAS, and ISGOTT.

3. Safety Risks—and Why Fenders Matter

Getting two LNG carriers close at sea carries risk. Wind, waves, and ship motion may cause collisions or damage to pipework, hoses, or emergency systems. LNG is highly flammable. Because of this, OCIMF rules demand careful risk checks, coordinated mooring, and certified fenders.

A tragic example occurred in 2019: a dry LNG transfer in the Kerch Strait led to a fire that killed 14 crew. This shows why good equipment—especially pneumatic fenders—is vital.

4. Core Equipment in LNG STS

Pneumatic fenders stand out—without them, you may risk damage to both ships.

5. Why Pneumatic Fenders Are the Preferred Choice

Pneumatic fenders, also called Yokohama fenders, offer:

• Low reaction force at small deflection—so ships don’t press hard in close quarter maneuvers.
• High energy absorption as ship motion compresses the air inside.
• Linear load-deflection response, which means predictable behavior.
• Compliance with ISO 17357, the standard for materials, strength, and testing of floating pneumatic fenders.

Companies like Trelleborg and Fendercare rely on pneumatic fenders for offshore STS protection.

Manufacturers generally offer hook-type, chain‑tyre net, sling‑type, or rib‑type models per ISO requirements.

6. NANHAI – Your Specialist in Marine Fenders

At NANHAI, we focus on designing and making ISO‑compliant pneumatic fenders for LNG STS and other marine needs.

What we bring:

1. High-quality pneumatic fenders (chain‑net, sling, hook types). We pack high-strength air hoses inside robust rubber walls that meet ISO 17357 levels.
2. Custom sizing, from small units up to 4.5 m diameter and 20 m length. We work with standard or high-pressure (50 kPa, 80 kPa) internal grades.
3. Energy-absorption math, helping you plan mooring energy and fender layout as per OCIMF Appendix H.
4. Global stock and prompt delivery—we advocate keeping inventory globally for quick dispatch and project operations.
5. Support packages, including technical selection, mooring layout, training, inspection plans, and repair schedules.

We deliver a full STS fender kit, including fenders, ropes, and guidance documents that help meet OCIMF, SIGTTO, and local port rules.

7. How NANHAI Meets Your Needs

• You provide your operational plan. We help confirm fender size and layout based on vessel displacement, approach speed, and sea state.
• You receive certified units. Each fender ships with ISO 17357 test records and quality certificates.
• You gain fast help. Need emergency replacement or change of size? We ship from nearby hubs or factories within days.
• You stay safe. We offer training on how to install fenders, use hoses properly, and execute mooring.

We understand that your success depends on equipment that just works—and gets you done fast.

8. Simple Next Steps

• Tell us your vessel size and STS specs.
• We send a quote and recommended fender layout.
• You assess, place your order, and we ship globally.

That’s your fast track to safer, smoother LNG transfer—with NANHAI as your trusted fender partner.

Thank you for your time.
If you want to see our past project sheets or get a quick quote, just ask—we’re always ready to support you.
NANHAI: we build the shield that guards your LNG transfer.