What mechanism is used to prevent chlorine cylinders from rupturing when exposed to excessive heat?

The mechanism that prevents chlorine cylinders from rupturing when exposed to excessive heat is the use of fusible plugs. Fusible plugs are designed to melt at a specific temperature, allowing gas to escape and thereby relieving pressure within the cylinder. This is crucial for safety, as it prevents the buildup of pressure that could lead to a catastrophic rupture of the cylinder in high-temperature conditions.

Fusible plugs serve as a fail-safe, activating in response to extreme heat, and are especially important for substances like chlorine, which can be hazardous. If the temperature rises to a dangerous level, the melting of the fusible plug ensures that gas can vent safely instead of causing the cylinder to explode.

Other mechanisms, such as pressure relief valves, safety caps, and thermal blankets, serve different functions or provide protection under different scenarios but do not specifically address the risk of heat-induced rupture in the same manner as fusible plugs.