Copper-Housed Rupture Disc for Gas Cylinder Applications

Posted on: Apr-06-2026

Manufacturer: Varem Technical Solutions LLP
Website: www.varemsolution.com

1. Product Overview

The Copper-Housed Rupture Disc is a non-reclosing, pressure-actuated safety device designed for integration into gas cylinder valves. The device protects cylinders from catastrophic rupture caused by excessive internal pressure resulting from fire exposure, overfilling, or elevated ambient temperatures.

The rupture disc is engineered specifically for:

CO₂ cylinders
CFC / Refrigerant cylinders
Liquefied compressed gas cylinders
Applications requiring CG-1, CG-4, and CG-5 configurations

This device bursts at a predetermined calibrated pressure to allow controlled gas venting and prevent structural failure of the cylinder.

2. Applicable Standards & Design Alignment

CGA Type CG-1 – Pressure-Activated Rupture Disc
CGA Type CG-4 – Rupture Disc with 165°F Fusible Alloy
CGA Type CG-5 – Rupture Disc with 212°F Fusible Alloy
DOT Cylinder Test Pressure Requirements
UL Certification Testing – Aligned (Testing in Progress)

3. Technical Specifications

Device Type: Non-reclosing rupture disc
Actuation Mode: Static pressure differential
Housing Material: Copper
Disc Material: High-strength metallic diaphragm (application dependent)
Size Range: From 3 mm ID × 8 mm OD to 10 mm ID × 16 mm OD
Burst Pressure Range: 30 barG to 425 barG
Burst Tolerance: ±7% of the requested burst pressure
Installation: Designed for valve body integration

4. Functional Principle

The rupture disc operates on differential pressure across a calibrated metallic diaphragm.

When internal cylinder pressure exceeds the specified burst rating:

The diaphragm reaches its tensile strength limit
Controlled rupture occurs
The opening allows rapid gas venting
Cylinder structural integrity is preserved

The device is single-use and must be replaced after activation.

5. Application Engineering Considerations

CO₂ Cylinders: CO₂ is stored as a liquefied compressed gas. Under fire or elevated temperature exposure, vapor pressure rises rapidly. The rupture disc prevents cylinder explosion by venting before structural failure.
CFC / Refrigerant Cylinders: Designed to manage pressure increases caused by thermal expansion of liquefied gases.

6. Design Advantages – Copper Housing

High thermal conductivity for improved heat response
Enhanced corrosion resistance in CO₂ environments
Excellent machinability for micro-size precision
Stable clamping geometry
Improved sealing integrity within compact valve bodies

7. Burst Pressure Engineering

Burst pressure is determined based on:

Cylinder service pressure
DOT minimum test pressure (typically 5/3 of service pressure)
Gas expansion characteristics
Valve assembly design constraints

Validated burst range achieved: 30 barG to 425 barG

Each production batch undergoes:

Hydrostatic / Pneumatic burst verification, following the UL testing guidelines
Dimensional inspection
Visual and surface inspection
Leak integrity validation

8. Performance Characteristics

Response Time: Instantaneous upon reaching burst pressure
Flow Capacity: Full opening for rapid depressurization
Reclosing: No (device must be replaced after rupture)
Fatigue Resistance: Withstands normal service pressure cycles below burst threshold

9. CGA Configuration Compatibility

CG-1: Pressure-actuated rupture disc. Most commonly used in CO₂ cylinders.
CG-4: Rupture disc backed by 165°F fusible alloy. Requires both elevated temperature and internal pressure rise for activation.
CG-5: Rupture disc backed by 212°F fusible alloy. Suitable for higher ambient temperature environments.

Our rupture disc is designed for integration into these valve assemblies based on OEM requirements.