External Fire Fighting System
This article is based on an External Fire Fighting system made by FFS Fire Fighting Systems, Norway for external fire fighting in Navy ships, coast guard ships, tugs or any other vessels. System Capacity 1000 Tons/Hour. Range 120 meters at an elevation of 50 meters. # Marine firefighting # Marine Fire Pumps
An external Fire fighting system is a fire fighting system used to extinguish fire happening at the shore or any other vessel on the sea by the Navy, the coast guard, tug or any other type of vessel.
These external fire fighting systems are essentially fixed on the Navy ships, coast guard ships or in tugs. These systems can be operated using a motor-driven pump or using an engine. Some ships have a separate clutch to couple the External firefighting pump into the main engine to get and high output.
Generally, these pumps have high outputs like 800- 1200 KW. Most of the systems have a capacity of 1000 Tons/ hour. Usually, the system is pressurized up to 10 to 15 bars.
Some systems can have more modes. Like, the system will be able to fire jet or AFF (Aqueous Film Foam). For this, the system should have a separate AFF tank. When operating in the Foam mode, the capacity of a common system reduces to 300 Tons/ Hour.
Fire monitors generate the jet/ spray and usually, they are fitted on the funnel deck of the ship. The performance of the system can be varied concerning the system characteristics.
The common systems have jet output in the range of 80-150 meters in length and 50 meters in height. These monitors can rotate up to 300 degrees and can achieve elevation from -20 to 80 degrees. This is done by a motorised system having an electrical supply of 415V, 3 Phase, 50Hz (Indian Region). The monitor Intel pressure is approximately 10 bars.
Clutching Interlocks for the Main Engine driven External Fi-Fi Pump
- Emergency Stop at Pull-Out Position.
- The suction Valve must be in an Open position.
- The discharge valve must be in a Closed position.
- “Read for Fi-Fi” mode should be illuminated on the Remote Control System (RCS) of the Steering Control System.
Operating Procedure of the External Fire Fighting Pump
- The main engine is to be run at idle RPM (400RMP).
- The main engine control should be in MCR.
- The main engine is to be clutched in zero pitch.
- Visual inspection pumps and accessories.
- Connect Remote Operating Panel (Joystick Control Panel) to the bridge or Flag Deck and report to MCR (Machinery Control Room).
- Switch on the power supply from the Power Distribution Box.
- Open Overboard Valve.
- Open the Bypass Valve from Fi-Fi Pump Control Panel at MCR and confirm the valve position physically.
- Open the Suction Valve from Fi-Fi Pump Control Panel at MCR and confirm the valve position physically.
- Clutch the Fi-Fi pump from the RCS control panel by pressing “PTO Clutch In”.
- Open the Discharge Valve when water comes out from the fire monitors.
- Handover Fi-Fi monitor controls to the bridge.
- Hand Over Main Engine controls to Bridge.
Before opening the Discharge Valve, it requires to open the Bypass Valve to check the operation of the system. The overboard valve is always open to remove the excess pressure inside the pipe system. Therefore, when only the Bypass Valve and Overboard Valve are open, most of the water content goes overboard from the Overboard Valve and a small amount of water goes through the fire monitors. From this step, it can be checked the system for any breakage or leakage.
After the checking process, the discharge valve is to be opened to increase the pressure on the monitors. After opening the Discharge Valve, the main engine RPM starts to increase slowly from 400RPM and it settles down at 600RPM. After this moment, the main engine won’t respond to the throttle position changes until clutch-out the Fi-Fi pump.
The controlling of the movements of the fire monitors can only be done from the Wheel House Control Panel or by the Joystick Control panel fixed to its connectors at the Port or Starboard bridge wings and Flag Deck.
- Take over control of the main engine to MCR from Bridge.
- De-clutch the Fi-Fi pump by pressing “PTO Clutch Out” at the RCS control panel.
- The main engine will come down from 600RPM to 400RPM within 20 seconds.
- Close the Discharge Valve.
- After draining water inside the pipes, close the Overboard Valve.
- Close the Suction Valve.
- Disconnect the Remote Control Panel (Joystick) from the Bridge Wings of the Flag Deck connector.
- Switch off the power supply to External Fi-Fi System from Power Distribution Box.
If you want to know about marine-type Automatic Fire Detection Systems and Sprinkler Systems, click the attached links.