Hose couplings are a connection fitting that is found on the end of a hose. The device makes it possible to connect the hose with another hose, or with some type of machinery or appliance. Usually constructed with brass or steel, a hose coupling may be designed in several basic patterns. Choosing the right hose coupling normally depends on the types of hoses involved as well as their intended use.
In many cases, hose couplings are designed to create a seal that is both airtight and watertight. This makes the devices especially helpful when the hoses are used to transport liquids or gases of some type. Some designs use either male or female thread designs, while others are classified as sexless hose couplings.
One of the more common types of hose couplings is known as the Storz coupling. This design requires very little effort to connect, as it requires no more than lining up the coupling with the device and locks in place with a simple quarter turn. A Storz hose coupler is often the choice of many municipal fire departments, as they make it possible to quickly attach a fire hose to a hydrant when attempting to bring a fire under control.
A variation on the Storz coupling is known as the Nakajima. This style of coupling also connects with a simple quarter turn. What is different is that hose couplers of this type also come with a locking device on the exterior. The lock can be especially helpful when connecting the hose to machinery that will move liquid or other agents through the hose at high pressures.
In Spain, the Barcelona hose coupling is common for use with fire trucks as well as connecting with local water systems when necessary. This design also makes use of a combination of male and female threads and must be screwed into place.
French fire fighters tend to utilize a hose coupling configuration known as the Guillemen Symmetrical Clutch. As with the Storz and Nakajima designs, this type of coupling connected with a simple quarter turn. Two protuberances are found on the exterior of the clutch, which allows the device to adjust to the hook of each hose as the ring turns during use.
The National hose coupling, also known as an NST, is also commonly used with fire hoses. Requiring more than a simple turn and lock process, the NST requires several full turns to complete the connection. The straightforward male and female thread combination makes it possible to quickly screw the coupling into position. A gasket helps to seal the connection. This type of coupling works well as a nozzle holder as well as several other hose accessories.
Most types of hose couplings are compact enough to allow the use of hose reels to retract and store the hoses when not in use. Hose fittings or adapters can also make it possible to connect a coupling to a device that otherwise not be compatible. Many factories, as well as fire fighters, will include some of these adapters in the standard equipment they keep on hand.