Fire protection for the mining and metals industry
Fire protection for the mining
Transformers and electrical switchgear are common in the mining and metals industry and so there is the ever present risk of oil fires. Alien Systems & Technologies Pyrogen and Pyrostorm extinguishing units are specially designed for these applications.
Pyrogen
The principle of the extinguishing action employed by Progen is unique. A special solid chemical, when electrically or thermally ignited, produces combustion products: micron sized dry chemical particles and gases. These dry chemical particles and the gaseous mixture combine to form a uniform fire extinguishing aerosol. Before being released in a protected area, the hot aerosol propels itself through a unique solid chemical coolant, which decomposes absorbing huge amounts of heat, thus ensuring flameless discharge and uniform distribution of the cool aerosol within the area.
The high rate of aerosol discharge ensures a tremendous knockdown effect. Micron-size aerosol particles exhibit gas-like 3D qualities that allow the agent to distribute throughout the enclosure and reach even the most concealed and shielded locations. Homogenous distribution is achieved in a matter of seconds, while long holding times all help to prevent fire re-ignition.
The unit can either be activated by a thermal cord attached to the module which activates at 175°C, or if the module casing temperature is greater than 500°C. Pyrogen is utilised, primarily, in the protection of switchgear compartments.
Pyrostorm
Pyrostorm modules are non-pressurised vessels, light in weight, easy to install and transport and with no special pipe work required. Activation can be achieved either by a heat sensing unit or through manual activation.
When activated, a chemical reaction within the module creates a positive pressure. The discharge diaphragm expands and ruptures, expelling the extinguishing powder at a rate of 35 m/s. The dry powder expelled from the Pyrostorm module creates two fire extinguishing mechanisms: chemically by removal of ‘chain carriers’ and physically by removal of heat and creating a fire blanket on the surface of the burning material, thus smothering the fire.
The units can be used alone or configured in a system with a voltage free heat activation device to provide electrical activation via temperature sensing without the need for batteries or electrical supplies. Pyrostorm can be configured for virtually any application and is ideal to protect industrial risks such as transformers, oil pack rooms and exposed pumps and motors.
Link to article: http://www.instrumentation.co.za/43808n
