FIRE FIGHTING PUMPS

Fire fighting pumps are a critical component of fire protection engineering systems providing the high-pressure water necessary to extinguish fires. The right selection of fire fighting pumps can be made by understanding their different types designed for specific safety needs. This article covers details about fire pump design, working mechanism, types, applications and sizing.

Fire Pump Working Mechanism

They are mainly categorized into two types: positive displacement pumps and centrifugal pumps.

Positive Displacement Pumps

Positive displacement pumps offer water suction out of a chamber. Their flow production mechanism is based on capturing a specified amount of water in each pumping cycle before discharging it. They are less commonly used with low flow volume and extremely high pressure making them suitable for specific applications such as fire sprinkler system engineering. They work with water mist and foam-water systems, and hence, used less frequently for firefighting purpose.

Centrifugal Pumps

Centrifugal pumps are used most commonly as compared to positive displacement pumps. They use rotatory motion of water to yield centrifugal force that helps in producing large water volumes at high pressure. This rotatory motion of water is generated by the bladed impeller. As the water enters suction inlet it is rotated by impeller and pushed to discharging edge with high pressure and volume.

Types of Fire Pumps

Fire pumps maintain a steady water flow to fire hoses and sprinkler systems for extinguishing fire quickly and safely. they are classified on the basis of their construction and working principles. Following are the main types:

Horizontal Split-Case Pumps

They are commonly known for efficiency and ease of maintenance but requires more installation space. Their design causes the water to split at the centre of the pump making it enter the impeller from both sides. These can be operated using both electric and diesel drivers.

Vertical Turbine Pumps

Vertical Turbine Pumps operate under negative suction pressure and are ideal for moving fluid from natural water bodies such as subgrade tanks and rivers. They are constructed with a series of impellers stacked vertically in a drive shaft assembly. Operating with diesel or electric drivers, they are usually used where the water source is below ground level, such as in wells and reservoirs.

In-Line Pumps

Powered only by an electric driver, in-line pumps are suitable for limited space applications with the maximum capacity of 1,500 gpm (5,678 L/min). They are available in both vertical and horizontal shafts (end suction type). The vertical configuration is complex because the pump drivers are located exactly above the pump, hence necessitating motor removal for pump maintenance purpose.

End Suction Pumps

End suction pumps occupy less space as compared to horizontal split case pumps which makes them suitable for small fire pump rooms. Their discharge outlets and the suction inlet make right angle with each other with the capacity of 1500 gpm (5,678 L/min). Available with electric motors or diesel engines they offer a range of pressures and water flow with simple installation and maintenance.

Multistage Multiport Pumps

High-pressure pumps with multiple ports or discharge outlets for increasing water pressure to meet specific pressure requirements of industrial and commercial buildings. The impellers are positioned in such a way that each port delivers different pressure.  They work in conjunction with the fire sprinkler system for increasing liquid pressure to meet the NFPA 13 or other national codes for fire protection systems. The multiple impellers inside a single casing are powered either by using electric motor or diesel.

Fire Pump Drivers

Fire pumps are powered by several drivers with unique features and benefits:

• Diesel Engine Drivers are reliable and economical, suitable for remote locations without electricity.
• Electric Motor Drivers are commonly used highly efficient devices which require less maintenance.
• Turbine Drivers resembles jet engines in working and are employed for high pressure and capacity demands.
• Hydraulic Motor Drivers are though costly but demonstrates energy-efficient behaviour with high-performance.
• Steam Drivers are less commonly used but require no external fuel or electricity source needed which makes them suitable for use in remote areasSizing a Fire Water PumpThe correct fire pump size can be chosen based on the following factors:

   Water flow rate – Determine the water flow rate needed for a building for fire protection systems including fire sprinkler system, foam systems, hose reels and other fire protection systems.

  Minimum flow rate of the system – Calculate the minimum flow rate which is required to meet the main fire protection system needs, i-e., the system’s most critical and longest pipe runs.

  Number of fire water pumps – Determine required number of fire pumps which normally depends on a maximum water flow rate for each pump.

  Pump size – Pump sizing can be done by taking into account the flow rate, number of impellers used and their size, type of impeller, size of suction line, discharge line, and drive.

  Compliance with Standards – Compliance with the national and international code such as ISO is mandatory for standardized operation.

   

   

   

  Fire Pump Accessories

  Fire fighting pumps come along with several accessories to function efficiently and accurately. These accessories are as follows:

  Pressure Gauges – They help in checking water pressure and providing insights about the correct pressure needed for each sprinkler for its proper operation.

  Discharge check valve – It prevents the backflow of water and makes it to flow in the intended direction.

  Safety valve – Safety valve prevents bursting of pipes when excess pressure is released during high temperature.

  Fuel tank – In case of fire eruption, it keeps the pump working by providing a constant flow of water.

  Silent enclosure – It helps to suppress the operational noise of the pump, hence making it quieter.

   

  Fire fighting pump price in Pakistan

  Fire Safety Equipment is one of the leading fire and safety equipment stockiest and supplier with its services spread all over Pakistan covering Islamabad, Lahore, Rawalpindi, Multan, Peshawar, Karachi etc. For all your needs of fire safety equipment or price estimates, please contact our sales team at whatsapp 03275007994 or email us sales@firesafetyequipment.com.pk contact us

  Conclusion

  Fire fighting pumps plays a most important role in the realm of fire fighting by providing sufficient water with pressure to combat fire. With various type tailored to specific needs, these pumps ensure that firefighting efforts are well-supported, enhancing the protection of lives and properties.The whole fire fighting setup is based on these pumps so their periodic maintenance and testing are very important so that they can perform well in case of any fire emergency.