Dual-Fuel Marine LNG Tank SPMT RoRo Audit Checklist

High-strength bridge ramp plates (yield ≥ 355 MPa) sized for dual-file SPMT wheel line contact pressure (≤ 16.5 tonnes/axle). Tapered finger flaps eliminate step impacts > 15mm.

Hydraulic stroke setting verified with minimum 350mm stroke reserve. Break-over crest and sag angles across quay-to-barge transition modeled to ensure zero tank belly grounding.

Barge secured with minimum 4 active constant-tension mooring winches (minimum 30-tonne line pull each) plus fail-safe shore steel wire deadman anchors preventing barge separation > 20mm.

Submersible ballast pump capacity (≥ 2,500 m³/hr total) mathematically matched to SPMT forward crawl speed (approx 1.5 m/min) to maintain barge deck elevation flush with quay ± 25mm.

Load-out scheduled strictly inside astronomical high-water slack window (≤ 0.2 m tidal change during roll-on). Redundant laser level and differential GPS receivers monitoring trim.

Ballast software calculation verifies barge internal shear force ≤ 75% and bending moment ≤ 70% of maximum allowable permissible limits throughout every incremental stage of roll-on.

Load distribution grillage beams aligned directly over barge internal longitudinal bulkheads and transverse web frames. Zero point loads placed on un-reinforced deck plating.

Cryogenic densified wood support blocks aligned precisely under permanent tank saddle pads. Saddle sliding lock pins engaged to arrest forward maritime surge acceleration.

Sea-fastening brackets, welded shear stoppers, and diagonal pipe struts inspected via Magnetic Particle Testing (MPI). Class-certified welding logbook signed by AWS/CSWIP inspector.

Vacuum reading < 0.05 mbar logged on digital Pirani gauge. Positive dry nitrogen blanket holding 0.35 bar(g). Pressure relief valve gagging clamps removed and verified free-floating.

Significant wave height Hs ≤ 0.5m inside harbor basin; sustained wind ≤ 18 knots (Force 5). No fog, dense squalls, or lightning threats inside 48-hour forecast envelope.

Class MWS representative present on-site. Formal Certificate of Approval signed authorizing departure of barge under designated ocean towage arrangements.