Fire hose

src: www.yankodesign.com

Fire hose is a high-pressure hose that carries water or other fire retardant (like foam) to fire to extinguish it. Outdoors, it attaches well to a fire engine or fire hydrant. Inside the room, it can be permanently attached to the building's upright pipe or pipe system.

The usual working pressure of firehose can vary between 8 and 20 bar (800 and 2,000 kPa; 116 and 290 psi) while per the NFPA 1961 Fire Hose Standards, the burst pressure exceeds 110 bar, (11,000 kPa; 1600psi)

Once used, fire hoses are usually suspended for drying, since standing puddles in the hose for a long time can damage the material and make it unreliable or unusable. Therefore, typical firefighting stations often have a high structure to accommodate the length of the hose for such preventive maintenance.

Sometimes, fire hoses are used for mass control (see also water cannons), including mainly by Bull Connor in Birmingham's campaign against demonstrators during the Civil Rights Movement in 1963.

Video Fire hose

History

Until the mid-19th century, most fires occurred because water was transported to the scene in a bucket. Original hand pumps dispose of their water through a small pipe or monitor attached to the top of the pump basin. New in the late 1860s the hoses became widely available to carry water more easily than hand pumps, and then the steam pumpers, to the fire.

In Amsterdam in the Netherlands, the Fire Brigade Inspector Jan van der Heyden and his son Nicholaas fired a fire to the next step by making the first fire hose in 1673. The length of 50 feet (15 m) of leather was sewn together like a boot leg. Even with the limitations of pressure, the hose installation to the gooseneck nozzle allows for a closer approach and more accurate water applications. Van der Heyden is also credited with an early version of a suction hose using a wire to keep it rigid. In the United States, fire hoses were introduced in Philadelphia in 1794. These canvas hoses proved to be non-durable, and stitched leather hoses were then used. Stitched leather hoses tend to erupt, so hoses made from leather tied together with copper rivets and washing machines were discovered by members of the Humane Selang Company in Philadelphia.

Around the year 1890, unlined stripes of flame made of woven woven circular yarn began to replace the skin hoses. They are certainly much lighter. When the hose fiber, made of hemp, becomes wet, they swell and tighten the fabric, causing the hose to be waterproof. Unlined hose, due to their lack of durability, was quickly replaced by a rubber hose in the use of city fire service. They continued to be used in interior hose lines and hose racks until the 1960s, and are still used in some areas for forestry applications.

After the discovery of the vulcanization process as a means to cure raw soft rubber into harder and more useful products, the fire service slowly transitions from large and unreliable hose to unlined linen tubes, then to layered rubber. Hose is lined and coated with reinforcement of interior fabrics. This rubber hose is very large, heavy, and stiff like a leather hose, but not easily leak. It also proved to be more durable than a striped linen hose. The wrapped construction resembles some of the hoses currently used by industry, for example, the fuel delivery hose used to serve the aircraft.

Maps Fire hose

The modern usage

Modern fire hoses use a variety of natural and synthetic fabrics as well as elastomers in their construction. These materials allow the hoses to be kept wet without decomposing and resist the damaging effects of sun exposure and chemicals. Modern hoses are also lighter than the old design, and this helps reduce physical tension on firefighters. Various devices are becoming more common that removes air from the interiors of fire hoses, commonly referred to as fire hose vacuums. This process makes the hose smaller and slightly stiffer, allowing more fire hose to be packed or loaded into the same compartment on the fire extinguisher.

Type

There are several types of hoses designed specifically for the fire department. Those designed to operate under positive pressure are called the drain hose. They include an attack hose, a supply hose, a relay hose, a forest hose, and a reinforcing hose. Those designed to operate under negative pressure are called suction hoses.

Another suction hose, called soft suction, is actually a flexible closed hose for use to connect a suction suction sucking flue with a pressurized hydrant. This is not a true suction hose because it can not withstand negative pressure.

Raw materials

In the past, cotton was the most common natural fiber used in fire hoses, but most modern hoses use synthetic fibers such as polyester or nylon filaments. Synthetic fibers provide additional strength and better resistance to abrasion. Fiber yarns can be dyed in various colors or can be left natural.

Coatings and coatings include synthetic rubber, which provides various levels of resistance to chemicals, temperature, ozone, ultraviolet (UV) radiation, mold, mildew, and abrasion. Different layers and coatings are selected for specific applications.

The hard suction hose consists of several layers of rubber and woven fabric that encloses an internal helix of steel wire. Some very flexible suction hoses use a thin polyvinyl chloride cover with a polyvinyl chloride plastic helix.

src: rawhidefirehose.com

Manufacturing process

Fire hoses are usually manufactured in factories specializing in providing hose products to city, industrial, and forest fires departments. The following is a sequence of operations commonly used to produce double jackets, rubber-coated rubber hoses.

Preparing the thread

• There are two different fiber threads that are woven together to form a hose jacket. The thread that runs down the hose is called a warp thread and is usually made of spun polyester or nylon filaments. They form the outer and inner surface of the jacket and provide abrasion resistance to the hose. The threads wrapped in tight spirals around the perimeter of the hose are called filler yarns and are made of filamentary polyester. They are trapped between the criss-crossing lusi yarn and provide the power to withstand internal water pressure. The rotary polyester warp yarn is specially prepared by the yarn manufacturer and sent to the hose factory. No further preparation is required.
• Polyester filamentary polyester is collected together in a bundle of 7-15 fibers and twisted on a twister frame to form a filler thread. The knitted and twisted yarn is then wrapped around a spool called the filler coil.

Weave the jacket

• The warp thread is staged on a creel, which will feed them long down through a circular loom. Two filler coils with filler threads are inserted into the loom.
• When the loom begins, the filler coil rolls the filler thread in a circle through the warp thread. As soon as the bobbins pass, the loom goes through each pair of adjacent ligature threads to trap the filler thread between them. The weaving process continues at high speed as the lower end of the jacket is gently pulled through the loom, and the coil continues to wrap the filler thread around the circumference of the jacket in a tight spiral. The woven jacket is wrapped around the take-up reel.
• The inside and outside jackets are separately woven. The inner jacket is woven with a slightly smaller diameter so it will fit inside the outer jacket. Depending on the expected demand, several thousand feet of jackets can be woven at a time. After review, both jackets are placed in storage.
• If the outer jacket is coated, it is pulled through a dye tank filled with coating material and then passes through the oven where the coating is dried and healed.

Extruding liner

• The softened, sticky, uncooked rubber block is inserted into the extruder. The extruder warms the rubber and pushes it out through the opening between the inner and outer circumferential solid pieces to form the tubular liner.
• The rubber layer is then heated in an oven where it undergoes a chemical reaction called vulcanization, or curing. This makes the rubber strong and flexible.
• The preserved liner passes through a machine called a rubber calendar, which forms thin sheets of non-dried rubber and wraps it around the outside of the liner.

Forming a hose

• Jackets and liners are cut to the desired length. The inner jacket is inserted into the outer jacket, followed by a liner.
• The steam connection is attached to each end of the hose assembled, and the pressurized vapor is injected into the hose. This causes the liner to swell against the inner jacket and cause a non-preserved rubber thin sheet to vulcanize and bind the liner to the inner jacket.
• The metal end joints, or joints, are attached to the hose. The outermost part of each clutch slips over the outer jacket and the inner ring is inserted into the rubber liner. A device called mandrel expansion is placed inside the hose and extends the ring. It squeezes the jacket and the liner between the ring and the gear on the outside of the clutch to form a seal along the hose.

Pressure test hose

• The standard set by the National Fire Protection Association requires that any length of a new double-jacket, rubber-lined attack hose should be tested to 600 psi (41.4 bar, 4,140 kPa) pressure, but most manufacturers test up to 800 psi (55.2 bar, 5,520 kPa). After delivery, the hoses are tested every year up to 400 psi (27.6 bar, 2,760 kPa) by firefighters. While the hose is under pressure, it is checked for leakage and to determine that the coupling is firmly attached.
• After the test, the hose is dried, dried, rolled, and shipped to the customer.

Quality control

In addition to final pressure testing, each hose is subjected to various inspections and tests at each stage of manufacture. Some of these inspections and tests include visual inspections, ozone resistance tests, accelerated aging tests, adhesion tests of bonds between the liner and the inner jacket, the determination of the number of laps under pressure, checking the dimensions, and more.

Future

The trend in fire hose construction over the last 20 years is to use lighter, stronger, lower maintenance materials.

This trend is expected to continue in the future as new materials and manufacturing methods evolve. One result of this trend is the introduction of a light supply hose in diameter was never possible before. A hose of up to 12 in (30.5 cm) with a pressure diameter of up to 150 psi (10.3 bar, 1,030 kPa) is now available. These hoses are expected to find applications in large scale firefighting industries, as well as in disaster relief and military operations.

Fire hoses come in different diameters. Light construction, single-jacket, ⁴ / ₄ , 1, and 1 ^{1 / ₂} inch inch diameter hose lines are commonly used in fire suppression applications. Double heavy duty, double-jacket, 1 2 , 1 / ₄ , 2, 2 ¹ / ₂ , and sometimes a 3-inch line is used for structural applications. The supply line, which is used to supply fire-fighting equipment with water, is often found in ¹ / ₂ , 4 , 4 ¹ / ₂ , 5 and 6-inch diameter.

There are several systems available for fixing holes in fire hoses, the most common being Stenor Merlin, which offers patch materials for Type 1, 2, and 3 hoses. The patches have two different sizes and two different colors (red and yellow). Patches are vulcanized to the hose and usually last a lifetime of hoses.

src: rawhidefirehose.com

Connection

Hose connections are often made of brass, although a hardened aluminum joint is also specified. In countries that use quick-action couplers for attack hoses, aluminum forging has been used for decades because of heavy brass penalties for storz couplers higher than threaded connections.

Threaded hose couplings are used in the United States and Canada. Each of these countries uses a different type of trafficking. Many other countries have standardized on quick-action clutches, which have no male and female ends, but connect the two. Again, there is no international standard: In Central Europe, the Storz connector is used by some countries. Belgium and France use Guillemin connector. Spain, Sweden and Norway each have their own quick clutch. Countries of former Soviet Union use Gost coupling. Baarle-Nassau and Baarle-Hertog, two municipalities on the Belgian-Dutch border, share the same international fire brigade. Fire trucks are equipped with adapters to enable them work with the Storz and Guillemin connectors.

In the United States, more and more departments use the Storz coupler for large diameter supply hoses, or other fast action clutches. Because their use is not standard, reciprocal tools may have compartments on their trucks dedicated to many hose adapters.

Different clutch hose styles have influenced fireground tactics. Equipment in the United States has "preconnects": The hose for a given task is inserted into the open compartment, and each attack hose is connected to the pump. Many time-consuming connections or problems with the tip of men and women are avoided with such tactics. In countries where the Storz (or similar) connectors have been used for attack hoses for generations, firefighters dropped manifolds at the border of the danger zone, which is connected to the equipment by a single supply line. As a result, the small hose "coupler" also affected the appearance and design of the fire apparatus.

src: rawhidefirehose.com

See also

• Hose bridge

src: cdn3.volusion.com

References

src: www.firesafetysupplier.com

External links

• Brief History of Fire Hose

Source of the article : Wikipedia