Hose Fittings
Definition
Hose fittings are the equipment fitted to a fire hose. Hose fitting is used to connect to the source of water supply, to another hose and to connect the required type of nozzles/branches.
Wrenches: A wrench is suitable for tightening the female coupling is provided. Tightening is essential since a small leak in the suction side will deprive the hydrant pump and the pump will lose suction of water.
Grouping. Broadly hose fittings are grouped as follows:
i. Couplings
ii. Branches
iii. Nozzles
iv. Fire Hydrant Valves
v. Breechings Valves
vi. Adaptors
vii. Hose Ramps
viii. Miscellaneous
ix. Collecting Heads and Suction Hose Fittings
Description.
i. Couplings
(a) General: These are metal fittings used for joining two lengths of hose together or a hose to an apparatus or vice versa. All couplings are always a pair of two pieces. One is called “male” and other “female” both in Aluminium and Gunmetal.
These are provided with the swivelling action for running the coils. The coupling is provided with threads to lock male coupling to female coupling are known as “Threaded”. The coupling is provided spring lock in female coupling is known as “Interlocking”.
(b) Components of Coupling:
(i) Delivery Hose
Male Coupling
a) Serrated Tail
b) Lip
c) Flange
Female Coupling
a) Serrated Tail
b) Two hollow lugs
c) Spring loaded plunger with cam shaped tooth
d) Stop nut
e) Cap
f) Metal Disc
g) Spring
h) Washer
(ii) Suction Hose Couplings
Male Coupling
a) Serrated Tail
b) Two fixed lugs
c) Externally threaded end
Female Coupling
a) Serrated Tail
b) Nut (threaded inside with four legs)
c) Sleeve
d) Washer
ii. Branches: The purpose of the branch is to increase the velocity of water and may be defined as “a metal fittings between hose and the nozzle that converts pressure energy into velocity energy to provide that nozzle a solid jet of water for firefighting”. Branch pipes and nozzles are commonly used for jet spray applications and can be connected to standard hose.
Types of Branches
Controlled Branches (Jet, Spray, Fog, etc. with control)
a) Hand Controlled Branches: This device can either get jet, jet & spray, alter to spray with independent control. By turning the rotating collar, anti-clockwise direction, the spray can be varied from a 300 cone to 1800 flat sheet. However, the jet size is not adjustable and depend on the 16mm or 19mm nozzle size. It can be as high as 22mm as the branch’s 1D would not allow.
b) Diffuser Branches: This branch can give spray or jet of variable size which can be shut off as may be required. The spray could be varied from an intense mist over an angle of 180° to a complete shut off.
c) Fog Nozzle Branches: This branch can be adjusted to give a water stream for straight jet, a fine or coarse spray and complete shut off. The fine spray is in the form of mist or fog, thus the name a floating rotary valve connected with the handle facilitates the control operations.
Uncontrolled Branches (Jet type)
a) Short Branch or Emergency Branch or Standard: It is only 8” (20cm) in length. It consists of a solid brass casting. The approximate weight is 2 Kgs for the threaded type and 1.64 for instantaneous type.
Fig: Stream Branch
c) Twin Branch: This is a relatively longer branch which bifurcates at the lower end, each leg terminating in a coupling for attachment to a line of delivery hose, thus being fed by twin lines of hoses; with this branch it is possible to get jets at larger velocities and greater quantities of water.
d) Extended Branch: It consists of 63 mm diameter 10 feet long steel pipes with a pointed head having a number of 1/8” holes on it. The other end has a thread on which may be screwed a collar containing a standard hose coupling or another 10 feet (3mm) section of piping to extend, the branch still farther.
Special Types of Branches
b) Double Revolving Branch: Double revolving branch consists of gun metal forming made in two parts. The upper part includes a collecting breeching to the outlet of which is connected casting which involves on ball bearing and carries four outlet which is at same space.
Two of them are in the form of branches completely different and fitted with standard nozzles. The other two also located opposite to each other are inclined to the diameter. It is rotated by the back pressure of water passing through two outlets inclined to the casting. This also is used to fight fires in ships holds/basements.
c) Cellar Pipe: Cellar pipe is an equipment to be used at smoky fires in basements of ships. It is fitted with a nozzle which can be made to elevate, depress and rotate by remote control. Total length is 4 ft 6 inches and can be folded when not in use.
d) Foam making Branch: Foam making branch are used for generating foam. At one end has a male coupling. The construction is so designed that air is drawn in due to the increase in velocity of the foam compound passing through the nozzle and creating a vacuum.
e) Super Jet Monitors: Super Jet Monitor is a special type of swivelling branch with nozzles fitted of bigger diameter 63mm these can be left unattended.
f) Monitors: Monitors are mounted on vehicles or fitted on fire hydrants which can handle large amounts of water. Single person can operate them.
e) Super Jet Monitors f) Monitors
iii. Nozzles:
iv. Fire Hydrant Valves: They are commonly used with fire hydrants and riser systems to regulate the flow or direction of water and are suitable for both on-shore and off-shore applications. Flow is regulated by simply rotating the hand wheel to open or closed the valve.
i. Double Headed type.
ii. Right Angle type.
iii. Straight type.
iv. Oblique type.
v. Bib Nose type.
vi. Horizontal type.
v. Breeching Valves: They are commonly used with fire hydrants and riser system to divide or collect water from two different sources.
a) Dividing Breech: Cast in gunmetal, brass or bronze, these are used to divide one line into two. These are “Y” shaped. Each of the two legs has a female coupling and the third leg has a male coupling.
b) Collecting Breech: Cast in gunmetal, brass or bronze, these are used to bond two lines of hose into one. These are also available in designs suitable for uniting two or more suctions to a common inlet. They are “Y” shaped. Each of two legs is fitted with a male coupling and a female coupling is attached to the third leg.
vi. Adaptors
a) Male-Male b) Male-Female
c) Threaded-Interlocking
d) Hydrant-Plugs
Hose Ramp: To facilitate crossing of vehicles over the charged delivery hoses, the ramps are placed over them. The ramps are so constructed as to have an angle of inclination on both sides. Ramps can be made to accommodate one or more hoses. These are made with wood or steel.
viii. Miscellaneous Hose Fittings
Nozzles
Turbo
Nozzle
Lever
Operated Jet Spray
Revolving
ix. Collecting Head and Suction Fittings
Collective Head
Foot Valve
Deep Lift Suction Fitting
a) Collective Head: Collective heads consists of a metal casting of aluminum or gunmetal fitting with two, three, four or six inlets for Delivery hose and a single Female suction coupling for attaching to the suction inlet of a pump. Each of the inlets is provided with a non-return valve which consists of a metal casing and screwed into the body of the collecting head and fashioned to a male instantaneous coupling. The valve is mushroom shaped with either a synthetic rubber or a metal ground face and is held against a seating by means of spiral spring. The water pressure forces the valve off its seating preventing the escape of water, getting fast stuck to its seating. The valve lift must not be less than 16mm.
These fitting are primarily used in closed relay when they are fitted to the delivery pumps. It may also be used at the end of suction hose to avoid repeated priming in case the pump needs to be stopped from time to time.
b) Foot valve: This consists of a metal suction strainer fitted with an extension tube in the casting between the strainer proper and the coupling. In this extension, a flap – type reflux valve is fitted in such a manner that, water rising up into the suction forces it open. If the pump is stopped the flow ceases immediately in the suction, the flap valve falls back on its seating, thus preventing the water from escaping and keeping the suction fully changed.
c) Deep Lift Suction: It consists of a light alloy body incorporating an inlet strainer plate and housing a two-stage ejector unit. The inlet connection is 63mm instantaneous make and outlet depends on the application. When used for Fire Services it usually has 102mm diameter outlet. Two eyes are provided for attaching the lowering ropes.
It takes delivery of high-pressure water from the normal fire pump and transfers the energy to a large volume of water at lower head. Lifts up to 80 feet are possible with this fitting.
Maintenance of Hose Fittings
a. Inspect and clean the fittings periodically.
b. All moving parts shall be oiled to ensure free operation.
c. Check washers for wear and tear.
d. Replace couplings which are reshaped and do not match properly.