6.1 LNG carrier (membrane type/spherical tank type)

Valve requirements: ultra-low temperature ball valve (-163℃), vacuum insulation valve, emergency shut-off valve (ESDV).

Technical challenges: adapting to ship body sway (inclination of 22.5°), vibration durability, and low-temperature sealing (to avoid BOG leakage).

Typical applications: liquid cargo tank inlet and outlet, re-liquefaction system pipelines, loading arm connection valves.

6.2 Offshore drilling platforms (semi-submersible/jack-up)

Valve requirements: Blowout Preventer (BOP) hydraulic control valve, seawater lift valve, mud gate valve.

Technical challenges: resistance to seawater chloride stress corrosion, explosion-proof (ATEX/IECEx), and resistance to typhoon impact.

Typical applications: water-separation system cutoff, ballast tank adjustment, and drilling fluid circulation pipeline.

6.3 Deep-sea oil extraction (underwater production system)

Valve requirements: subsea ball valve (ROV operation), subsea gate valve, subsea throttle valve.

Technical challenges: withstanding hydrostatic pressure at a water depth of 3000 meters (30MPa), hydrate inhibition (temperature control/alcohol injection), and ROV interface compatibility.

Typical applications: main valve and wing valve of Christmas tree, subsea manifold end connection, emergency shut-off of flowline.