Ship-to-Ship Transfer Fenders — Vessel-Pair Sized, ISO 17357-1:2014 Certified

For Aframax-to-VLCC STS transfers, 3300 mm x 6500 mm pneumatic fenders at 50 kPa IIP are the standard specification. Where freeboard differential is large, open-water conditions apply, or the berthing energy calculation per OCIMF MEG4 Section 6 produces a higher energy requirement, 4500 mm x 9000 mm may be required. Final sizing depends on combined displacement, approach velocity, and allowable hull pressure on the Aframax hull. Share your vessel pair and we will confirm the recommendation. See the pneumatic fender size chart for the full reference.

OCIMF MEG4 Appendix B defines minimum fender performance criteria for ship-to-ship transfer operations. Requirements include minimum energy absorption at rated deflection, maximum allowable reaction force relative to hull pressure limits, and a documentation package covering test certificates, inspection records, and material certifications. MEG4 Section 6 covers the operational STS context: fender deployment, recovery, and inspection protocols. JettyGuard provides MEG4 Appendix B compliance documentation as standard scope on every STS fender order.

Pneumatic fenders are the standard for STS operations, referenced in OCIMF STS Transfer Guidelines and MEG4 Appendix B. They handle repeated compression cycles without permanent deformation, offer higher energy absorption per unit weight for crane deployment, and are the referenced fender type across all major STS operational standards. Foam-filled fenders are designed for permanent quay-wall installations, donut fenders for SBM/mooring buoys, and fixed berths where the fender is not recovered between operations.

Most tanker STS operations deploy 4 to 6 pneumatic fenders per vessel interface. The exact count depends on vessel length, freeboard differential, contact area distribution, and the operating environment. OCIMF STS Transfer Guidelines provide minimum coverage recommendations based on vessel class. For VLCC-to-VLCC operations, 6 fenders is common. For Aframax-to-Suezmax, 4 fenders typically provides adequate contact coverage. JettyGuard specifies fender count as part of the sizing recommendation.

Tire-chain net protection is required, not optional, for STS fender deployment. The tire net distributes contact loads across the fender surface, protects the rubber body from abrasion and point loading during vessel-to-vessel contact, and extends service life in demanding offshore conditions. Chain rigging (chains, shackles, swivels) connects the fender to the vessel hull and must be rated to the fender mooring load. JettyGuard supplies fender + tire-chain net + rigging as one package under a single PO.

A well-maintained pneumatic fender in STS service typically operates for 8–12 years. Lifespan depends on operating frequency, compression cycles per deployment, environmental exposure (UV, saltwater), and handling practices during deployment and recovery. Regular inflation pressure checks, visual inspection of the rubber body and tire-net condition, and proper storage between operations extend service life. ISO 17357-1:2014 Clause 8 prototype test certificates document baseline performance at delivery. Periodic re-testing verifies continued compliance.

ISO 17357-1:2014 defines Type I (net-type, with chain-tire net protection — the standard for STS operations) and Type II (sling-type, no net). Clause 8 requires a full-scale prototype performance test at rated IIP with energy absorption, reaction force, and dimensional measurements documented. Clause 9 requires commercial batch testing on every production order. STS service providers and OCIMF-compliant operators specify Clause 12 third-party inspection for independent verification.

Standard production lead time is 4–8 weeks from PO. ISO 17357-1:2014 with Clause 12 third-party inspection (BV / DNV GL / ABS) requires 8–14 weeks. Third-party inspection is scheduled into the production plan at order confirmation, not added later. CIF delivery to Asia-Pacific anchorages (Singapore, Brisbane, Indonesia, Malaysia) adds 2–4 weeks for sea freight, depending on port. Total PO-to-anchorage: 6–18 weeks. Lead time is committed at PO. The mobilization window is part of the production schedule.

Same mold-process production method. Same multi-ply cord construction. Same ISO 17357-1:2014 prototype testing and Clause 12 third-party inspection. The price difference reflects manufacturing location and supply chain length, not production method or material specification. The right quality question is not which brand is on the fender. It is which production method was used and whether the certificate documents individual testing. JettyGuard produces every STS fender via mold-process vulcanization with prototype testing at rated IIP, the same method Yokohama and Trelleborg use.