As printed in the December 2013 issue of WHEN (Waste Handling Equipment News).
Fire suppression systems are becoming more and more common due to the mandates in mines, above ground and below, along with some insurance companies requiring systems on insured machinery. In addition, with the increased pressures and complexity of hydraulics and the advent of Tier IV engines and their associated excess heat, fires could potentially increase.
So for real facts, I spoke with Kenneth Daniels of AFEX Fire Suppression Systems. AFEX call themselves the heavy equipment experts because that's all they service, heavy equipment. AFEX is in most major mines in the world, have CAT® endorsed products, and their systems are engineered into some John Deere® products. Without giving me the AFEX sales pitch, he explained why I had heard complaints about fire suppression systems in the past.
Myth 1: Fire Suppression Systems are Too Expensive
A sufficiently sized and installed fire suppression system depends on the size, horsepower, and hydraulics of the machine. The more of each, the larger the system. This is not a one-size-fits-all industry. Stationary, not just mobile equipment can also catch fire. While the machine loss may be an issue, the building it is inside, the mulch pile it is next to, and the landfill that is on, can be the greater issue that can cost you your business. Think about what equipment is the most critical to your business and what would happen if it caught fire. What would be the collateral damage associated with it? It is possible that your insurance rates can be reduced with this type of protection? Check with your carrier.
Myth 2: Systems Leak and Become Ineffective
Some systems are pressurized, which means the tanks contain both the propellant and the agent, like the fire extinguisher that hangs on the wall in your office. Over time they have the possibility for pressure to leak out because of the significant vibrations these machines have, which can keep the system from discharging fully or at all. This is a maintenance item that needs to be monitored on a daily basis. Concerned? Look at a differently designed side cartridge operated system that uses a sealed, pressurized nitrogen cylinders separate from the agent tanks so that leaking won't be an issue. Get a more detailed description from your fire suppression supply company.
Myth 3: Suppression Systems Are in the Way
Some manufacturers have predesigned systems, such as the John Deere® Feller Bunchers, but most systems are designed in the office and installed on site. Because these are aftermarket installations, the sensors and the spray nozzles need to be where the potential fire hazard could be. It’s rather easy to remove some stainless steel tubing, like AFEX uses, and make your repairs or do your service.
What Does a Basic System Consist of and How Does it Work?
- Dealer sends machine drawings to manufacturer or distributor for a Fire Risk Assessment to determine protection, distribution, and discharge configuration. They also determine the type of agent required for the risk.
- The amount of agent required, is determined by the size of the machine, the horsepower, and hydraulic system size and pressures. Dealer installs engineered routing of steel tubing or hydraulic hoses, sensors and spray nozzles and storage tanks. Agent storage tanks are installed in an area with enough space and away from potential damage. Space for these tanks can be an issue.
- Then manual switches are installed so an operator can activate the system at the first sign of trouble.
- Sensors, set at approximately 300 degrees, are activated by heat or fire. The sensors trigger the tanks to open. The spray nozzles send the agent to the predetermined areas and continually spray until the tanks are empty. Liquid systems take much more material to cover compared to dry chemical. So you need much more space for storage tanks of liquid than dry chemical.
- With all the electronics and hybrid machines today, “liquid only” is not a good option in most cases. Dry chemical will cover Class A (combustibles), Class B (fuel), and Class C (electrical) fires. Dual systems are possible also and perform to the strengths of each agent.
- A side cartridge system has a nitrogen tank which is activated by the temperature sensors, which then activates the agent tanks. In AFEX systems, they use of stainless steel tubing which adds to the strength, rigidity and longevity of the overall system. This makes the system much more user friendly because the lines are much easier to remove for maintenance and repair.
A fire suppression system does not mean daily housekeeping is not necessary. Most fires start within an hour of being shut down and most are from the lack of housekeeping. These systems can only go off once and making sure they can takes a little maintenance. To reiterate, with all the vibration, dust, and dirt, these systems need quarterly service to make sure they can do what they were made to do.
This is one major cost you don’t want to have, but one major disaster that can be avoided. Next equipment purchase check out a system and start protecting yourself.
By: Dave Whitelaw, The Grinder Guy, [email protected]