Capped
by Wild Thing
Title
Capped
Artist
Wild Thing
Medium
Photograph - Photography
Description
Fire Hydrant:
A fire hydrant, also called fireplug, is a connection point by which firefighters can tap into a water supply. It is a component of active fire protection.
The user attaches a hose to the fire hydrant, then opens a valve on the hydrant to provide a powerful flow of water, on the order of 350 kPa (50 lbf/in�) (this pressure varies accord-ing to region and depends on various factors including the size and location of the at-tached water main). This user can attach this hose to a fire engine, which can use a power-ful pump to boost the water pressure and possibly split it into multiple streams. One may connect the hose with a threaded connection, instantaneous "quick connector" or a Storz connector. A user should take care not to open or close a fire hydrant too quickly, as this can cause a water hammer, which can damage nearby pipes and equipment. The water inside a charged hose line causes it to be very heavy and high water pressure causes it to be stiff and unable to make a tight turn while pressurized. When a fire hydrant is unob-structed, this is not a problem, as there is enough room to adequately position the hose.
Most fire hydrant valves are not designed to throttle the water flow; they are designed to be operated full-on or full-off. The valving arrangement of most dry-barrel hydrants is for the drain valve to be open at anything other than full operation. Usage at partial-opening can consequently result in considerable flow directly into the soil surrounding the hy-drant, which, over time, can cause severe scouring. Gate or butterfly valves can be in-stalled directly onto the hydrant orifices to control individual outputs and allow for changing equipment connections without turning off the flow to other orifices. These valves can be up to 12 inches in diameter to accommodate the large central "steamer" ori-fices on many US hydrants. It is good practice to install valves on all orifices before using a hydrant as the protective caps are unreliable and can cause major injury if they fail.
When a firefighter is operating a hydrant, he or she typically wears appropriate personal protective equipment, such as gloves and a helmet with face shield worn. High-pressure water coursing through a potentially aging and corroding hydrant could cause a failure, injuring the firefighter operating the hydrant or bystanders.
Appearance:
Hydrant coloring may be due to either purely practical criteria or more artistic. In the United States, the AWWA and NFPA recommend hydrants be colored chrome yellow[1] for rapid identification apart from the bonnet and nozzle caps which should be coded ac-cording to their available flow. Class AA hydrants (>1500 gpm) should have their nozzle caps and bonnet colored light blue, Class A hydrants (1000�1499 gpm), green, Class B hydrants (500�999 gpm), orange, Class C hydrants (0�499 gpm), red and inoperable or end-of-system (risking water hammer) black. This aids arriving firefighters in determining how much water is available and whether to call for additional resources, or find another hydrant. Other codings can be and frequently are used, some of greater complexity, in-corporating pressure information, others more simplistic. In Ottawa, Ontario, hydrant col-ors communicate different messages to firefighters; for example, if the inside of the hy-drant is corroded so much that the interior diameter is too narrow for good pressure, it will be painted in a specific scheme to indicate to firefighters to move on to the next one. In many localities, a white or purple top indicates that the hydrant provides non-potable water. Where artistic and/or aesthetic considerations are paramount, hydrants can be ex-tremely varied, or more subdued. In both instances this is usually at the cost of reduced practicality.
Uploaded
February 4th, 2017
Statistics
Viewed 235 Times - Last Visitor from Fairfield, CT on 04/20/2024 at 3:55 AM
Embed
Share
Sales Sheet
Comments
There are no comments for Capped. Click here to post the first comment.