Bryant Ward, the Executive Vice President of Engineering at Liebherr Mining Equipment Newport News, Virginia, fields questions from African Mining Brief on the merits of having vehicle fire suppression systems factory-installed and intricacies involved in the process of installation.
AMB: From Liebherr’s perspective, what are the advantages of using a factory-installed fire suppression system in a vehicle over self-installation (where a mining company engages a fire suppression company to do the installation instead)?
BW: Fire suppression companies cannot always know the best places to weld, and may unintentionally compromise structural integrity of the mining truck. Factory-fitted solutions result in a better quality of fit and finish, reliability, and safer placement in regards to fuel and ignition sources.
Liebherr supports customers in selecting and deciding how to safely install fire suppression systems on Liebherr mining trucks.
Liebherr relies on fire suppression subject matter experts to provide the required information about the latest fire suppression agents and suppression technologies. Liebherr offers automatic fire suppression on the T 264 and T 284 mining trucks, because operator and personnel safety is of paramount importance.
AMB: What are the key factors you consider prior to installing a fire suppression system in a vehicle?
BW: Two factors that are most critical when it comes to fire suppression are fuel and ignition sources. Each truck differs by size, class and manufacturer.
Twin agent fire suppression is widely considered to be the safest option. A dry chemical extinguishes flames, but fuel and heat from the vehicle can always reignite it. To prevent this short coming re-ignition, a wet chemical foam agent suffocates the potential fire and cools the ignition source.
AMB: What role does a company supplying a fire suppression system play in the design of a vehicle?
BW: Liebherr covers exhaust pipes with fire and oil resistant wrapping where there are risks for fire ignition.We take measures to keep temperatures lower than the ignition point or segregate areas of fuel and ignitions sources with shielding, wrapping, or in design.
The fire suppression suppliers have limited input on the design of a vehicle, so Liebherr engineers create as many safety opportunities as possible in the design of the haul trucks. It is a close collaboration on compiling and reviewing risk assessments with fire suppression suppliers.
AMB: Would you share with us special features of standard vehicle fire suppression systems and how they enhance safety?
BW: Most everyone agrees on the twin agent method of fire suppression, many differ on the type of automatic detection used to initiate the system. Different methods of activation include:
- Thermal spot/Temperature sensors: A preset temperature is determined to initiate the fire suppression system.
- Linear wire: A cable connects all the canisters of dry and wet chemical agents. If the wire burns or melts, the system activates.
- Infra Red sensors: Sensor “eyes” detect danger in the form of a fuel-fed fire and activates system instantly. This method is the most advanced, capable of detecting 1 square foot of flame energy.
Ultimately, the correct solution for any given customer depends on the customer’s safety needs. Following the principles of a risk assessment, customers can mitigate a high-risk location with a more advanced detection solution, or even a combination of available detection methods.