Fire hydrants are a critical piece of any emergency response system. Since their creation, they have revolutionized and greatly improved the way we fight fires. Today’s fire hydrants are mostly dry barrel style, meaning they have the ability to pump water out when needed and shut the water off when it’s not needed — mostly to prevent the water from freezing in cold conditions.
While the overall design of a hydrant is relatively standard, there are still many moving parts for firefighters to pay attention to — especially fire hydrant valves. There are four main types of valves on a fire hydrant — the gate, butterfly, check and plug valves. These hydrant valves are at the bottom of fire hydrants, and their job is to open and close the plug that allows water to flow. When open, a valve fills the hydrant with water while sealing drain holes so that the water is ready to use. When closed, the valve prevents water from entering the fire hydrant and drains excess water through drain holes.
So, what are the different types of valves, and what are they used for? Read on to learn more about each one and its benefits for firefighting missions.
What Is a Gate Valve?
The gate valve is the most common type of fire hydrant valve. More likely than not, your municipality has hydrant gate valves. These valves are made for controlling water flow without damaging the fire hydrant itself, which is why they’re the most common firefighting hydrant valve.
Gate valves in fire hydrants are simply used to turn the water on and off. They often include a crank handle that makes it much easier for firefighters to quickly get water flowing in an emergency. These valves are most commonly made from cast iron and coated with a type of rubber to prevent wear and corrosion from the flow of water over time. Gate valves are also best for use in old hydrants or cold weather because they can throttle the water in a pipeline even when water is slow to flow or is flowing uncontrollably.
What Is a Butterfly Valve?
Another type of critical fire hydrant valve is the butterfly valve. These valves are best used for controlling the flow of water in hydrants. They are operated by a disc system that turns the valve 90 degrees to an open or closed position. However, a very small section of the butterfly valve is open at all times, whereas gate valves must be completely open or closed. The disk is operated by a handwheel which turns the valve to the open or closed position.
Butterfly hydrant valves can also be used in tandem with other equipment to create a position indicator for firefighters to see whether or not the valve is closed at a given time. Butterfly valves are typically cheaper, lighter and easier to use than hydrant gate valves due to their ability to operate under lower torque than gate valves. This has positioned butterfly valves as an up-and-coming firefighting hydrant valve that many installers prefer. It’s possible that, in the future, butterfly valves could replace gate valves as the most common critical fire hydrant valve, so it’s important for firefighters to keep an eye on these valve types in hydrants.
What Is a Check Valve?
The next most popular type of fire hydrant valve is a check valve. These valves are specially designed to prevent hydrant water from backing up and otherwise affecting municipal water systems. Typically, the water used for firefighting comes from multiple sources, including municipal water. However, sometimes issues can occur — hydrant water can be mixed with drinkable water, contaminating it, or water from fire sprinklers might end up in street drains that lead to municipal water systems. This contamination of municipal water is known as backflow.
The purpose of check valves is to prevent backflow. These valves only open in one direction when water flows out, so backflow is completely prevented. Check valves are great options for municipalities where contamination is an issue or where backflow needs to be prevented.
What Is a Plug Valve?
Plug valves are the least common type of critical fire hydrant valves because they are typically used more in wastewater applications rather than for firefighting. Due to the need for much greater force because of their high friction, it’s much more difficult for materials to flow through plug valves. Therefore, these valves aren’t recommended for typical firefighting water usage.
Plug valves are most commonly used in municipal waste management systems for controlling and distributing contaminated liquids or sludge. They can be used both above and below ground. There are four types of plug valves — lubricated, nonlubricated, expandable and eccentric all used for different applications, depending on the materials used within the systems.
Similar to butterfly valves, plug valves can either completely isolate a liquid or allow for the flow of liquid. These valves are also used in applications like oil and gas extraction or mining to prevent contaminants from affecting important water sources. Plug valves are made with strong metals to handle abrasive particles that may be flowing through them.
Contact Bunker Gear Specialists to Order Your Critical Fire Hydrant Valves
Fire hydrants are an essential and critical piece of any emergency response system. It’s important for firefighters, municipal workers and others to be aware of the various types of fire hydrant valves and able to identify and operate them in emergencies. When the next emergency occurs, you won’t waste time trying to get water to flow because you don’t understand the system. Prepare ahead of time by knowing the different fire hydrant valve types and how they work.
Bunker Gear offers top-of-the-line equipment for all firefighting needs, from helmets to clamps. Our gate valve is ready to go and will handle your water sources with ease, even in the toughest situations. Contact us today for more information about our equipment and learn how we can help you continue saving lives.