(Content Translation)
The LNG cryogenic breakaway valve (Emergency Release Coupling - ERC) operates through a precision-engineered mechanical mechanism designed to activate under predetermined emergency conditions. Its working principle involves:

1. Dual-Activation Mechanism:

• Mechanical Overload Trigger:
  When excessive force (e.g., tension from a drifting ship or displaced truck) exceeds the valve’s calibrated threshold, a shear-prone structural component fractures. This instantly severs the connection while simultaneously triggering internal spring-loaded seals to isolate both sides of the pipeline.

• Manual Emergency Release:
  A pull-cable system allows operators to remotely activate the valve from a safe distance during crises (e.g., fire, leak), ensuring immediate disconnection without approaching the hazard.

2. Instant Sealing Action:

• Upon activation, dual ball valves or poppet seals snap shut within milliseconds, preventing LNG leakage (-162°C) by creating a leak-tight barrier on both ends of the severed connection.

3. Cryogenic Adaptation:

• All components (e.g., seals, fracture elements) are manufactured from cryogenically rated materials (e.g., stainless steel 316L, PTFE) to maintain functionality and structural integrity at -162°C.

4. Single-Use Safety Design:

• The valve is non-reusable after activation. The sacrificial fracture mechanism ensures reliability but mandates replacement post-triggering.

Key Takeaway: This principle balances passive mechanical reliability with active human intervention, aligning with ISO 28460 and OCIMF standards for LNG transfer safety. The design prioritizes zero leakage during failure scenarios.

(Note: "Breakaway Valve" is used for general comprehension; "ERC" is the formal term in technical documentation.)