Offshore Zone 2 Pressurized Container is a pressurized transport unit designed for hazardous areas (Zone 2) of offshore oil and gas platforms. It must meet both DNV 2.7-1 standards and ATEX explosion-proof certification (such as II 2G Ex db IIC T4) to ensure safety and reliability in explosive gas environments. The following is a detailed analysis of its core technical requirements and industry applications:

1. Core technical requirements and design features

Material and structure

High-strength steel: S355J2+N or equivalent steel is used, the welding process complies with EN ISO 15614, and the welds pass non-destructive testing (such as ultrasonic testing).

Corrosion-resistant design: The surface is sprayed with a high weather-resistant coating (such as Hempadur), which passes the salt spray test for ≥1000 hours and has a service life of more than 20 years.

Pressure and sealing system

Pressure range: The design pressure is usually 200-300 bar (such as the case of CO₂ transportation in the North Sea oil field), equipped with safety valves, pressure switches and emergency pressure relief devices to ensure automatic discharge in case of overpressure.

Sealing design: Double-layer sealing door (IP65 protection level) and special sealing strips are used to reduce gas leakage rate by more than 30%.

Explosion-proof and safety design

ATEX certification: The electrical system must comply with Ex db explosion-proof standards (such as explosion-proof motors, lighting equipment), the housing protection level is IP65, and the internal gas concentration monitoring system is configured.

Temperature control and energy: Supports precise temperature control from - 60°C to + 50°C, and optional diesel generators (such as 15kW Clip-On Genset) are available, which improves fuel efficiency by 15%.

2. Certification process and test standards

Certification basis:

DNV 2.7-1: covers the entire process of design, manufacturing and testing, and requires passing static load test (3 layers stacked), dynamic impact test (drop height 0.6 meters) and vibration test (5-50Hz).

ATEX Directive 2014/34/EU: requires equipment to be explosion-proof in Zone 2 environment, and electrical equipment must pass type test certification (such as Ex db IIC T4).

Test items:

Pressure test: Hydrostatic pressure test verifies the strength of the container to ensure compliance with ASME VIII or API 20S standards.

Explosion-proof test: simulates explosive gas environment to verify the sealing of the shell and the explosion-proof performance of electrical equipment.