API 6DSS Subsea Valves vs API 6D: What’s the Critical Difference?
Compare API 6DSS and API 6D valves by operating environment, materials, corrosion protection, testing, isolation design, and actuation requirements. API 6D applies mainly to surface and onshore pipeline valves, while API 6DSS adds specialized requirements such as hyperbaric testing, subsea corrosion resistance, and ROV-compatible operation for offshore and underwater oil and gas systems.