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| {{For|the "ball valves" found in UK toilet cisterns and attic tanks |float valve|ballcock}}
| | The author is known by the url of Latoria. Puerto Rico exactly where her home is. Auditing is how he supports his loved one. It's not a known thing but what she likes doing is lacemaking but she has been taking on new things lately. Check out my website here: http://euroseonews.wordpress.com/ |
| {{Refimprove|date=August 2012}}
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| [[Image:Seccion valvula de bola.jpg|250px|right|thumb|Cut-away view of a ball-valve mechanism]]
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| [[File:Ball.PNG|150px|thumb|right|Cutaway view of a simple manual ball valve. 1) Body 2) Seat 3) Disc (ball) 4) Handle (Lever) 5) Stem]]
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| A '''ball valve''' is a [[valve]] with a [[spherical]] disc, the part of the valve which controls the flow through it. The sphere has a hole, or port, through the middle so that when the port is in line with both ends of the valve, flow will occur. When the valve is closed, the hole is perpendicular to the ends of the valve, and flow is blocked. The handle or lever will be inline with the port position letting you "see" the valve's position. The ball valve, along with the [[butterfly valve]] and [[plug valve]], are part of the family of ''quarter turn valves''.
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| Ball valves are durable and usually work to achieve perfect shutoff even after years of disuse. They are therefore an excellent choice for shutoff applications (and are often preferred to [[globe valve]]s and [[gate valve]]s for this purpose). They do not offer the fine control that may be necessary in throttling applications but are sometimes used for this purpose.
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| Ball valves are used extensively in industrial applications because they are very versatile, supporting [[pressure]]s up to 1000 [[bar (unit)|bar]] and [[temperature]]s up to 482°F (250°C). Sizes typically range from 0.2 to 11.81 inches (0.5 cm to 30 cm). They are easy to repair and operate.
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| The body of ball valves may be made of [[metal]], [[plastic]] or metal with a [[ceramic]] center. The ball is often [[chrome plating|chrome plated]] to make it more durable.
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| A ball-check valve is a type of [[check valve]] with a ball without a hole for a disc, and is not covered in this article.
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| The [[genericized trademark]] ''ball-o-fix'' is occasionally used after the original [[UK]] market leader.{{Citation needed|date=November 2009}}
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| The Ballofix was invented by the Danish company [http://www.broen.com Broen], and are still in production.
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| ==Types of ball valve==
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| There are five general body styles of ball valves: ''single body'', ''three piece body'', ''split body'', ''top entry'', and ''welded''. The difference is based on how the pieces of the valve—especially the casing that contains the ball itself—are manufactured and assembled. The valve operation is the same in each case.
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| [[Image:Duplex-valve-A182-F51.JPG|200px|right|thumb|Duplex ball valve]]
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| In addition, there are different styles related to the [[boring (manufacturing)|bore]] of the ball mechanism itself:
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| * A ''full port'' or more commonly known ''full bore'' ball valve has an over-sized ball so that the hole in the ball is the same size as the [[pipeline transport|pipeline]] resulting in lower friction loss. Flow is unrestricted but the valve is larger and more expensive so this is only used where free flow is required, for example in pipelines which require [[pigging]].
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| * In ''reduced port'' or more commonly known ''reduced bore'' ball valves, flow through the valve is one pipe size smaller than the valve's pipe size resulting in flow area being smaller than pipe. As the flow discharge remains constant and is equal to area of flow (A) times velocity (V), <math>A_1V_1=A_2V_2</math> the velocity increases with reduced area of flow.
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| * A ''V port'' ball valve has either a 'v' shaped ball or a 'v' shaped seat. This allows the orifice to be opened and closed in a more controlled manner with a closer to linear flow characteristic. When the valve is in the closed position and opening is commenced the small end of the 'v' is opened first allowing stable flow control during this stage. This type of design requires a generally more robust construction due to higher velocities of the fluids, which might damage a standard valve. These can be referred to as a type of control valve but are not as accurate as a balancing valve, needle valve, globe valve, or pressure regulating valve.
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| * A Kompact ball valve is a "full port" valve that fits between 2 flanges. Due to its configuration, its body is slimmer however and less metal. <ref>{{cite web|title=ValveMan Brand Kompact Series Wafer Type Ball Valve|url=http://www.valveman.com/valves/valve-series/valveman-brand-kompact-series-wafer-type-ball-valve/|publisher=ValveMan|accessdate=18 June 2012}}</ref>
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| * Cavity filler Ball Valve. Many industries encounter problem with residues in the ball valve. Where the fluid is meant for human consumption, residues may also be health hazard, and when where the fluid changes from time to time contamination of one fluid with another may occur. Residues arise because in the half open position of the ball valve a gap is created between the ball bore and the body in which fluid can be trapped. To avoid the fluid getting into this cavity, the cavity has to be plugged, which can be done by extending the seats in such a manner that it is always in contact with the ball. This type of ball valve is known as Cavity Filler Ball Valve.
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| There are a few types of ball valves related to the attachment and lateral movement of the ball:
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| * A [[trunnion]] ball valve has additional mechanical anchoring of the ball at the top and the bottom, suitable for larger and higher pressure valves (say, above 10 cm and 40 bars).
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| * A floating ball valve is one where the ball is not held in place by a trunnion. In normal operation, this will cause the ball to float downstream slightly. This causes the seating mechanism to compress under the ball pressing against it. Furthermore, in some types, in the event of some force causing the seat mechanism to dissipate (such as extreme heat from fire outside the valve), the ball will float all the way to metal body which is designed to seal against the ball providing a somewhat failsafe design.<ref>{{cite web | url=http://www.fbvalve.com/Floating-Ball-Valve.html | title=What We Do >> Floating Ball Valve | publisher=FBV Inc. | accessdate=August 22, 2012}}</ref>
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| Manually operated ball valves can be closed quickly and thus there is a danger of [[water hammer]]. Some ball valves are equipped with an [[actuator]] that may be [[pneumatically]] or [[Electric motor|motor]] operated. These valves can be used either for on/off or flow control. A pneumatic flow control valve is also equipped with a positioner which transforms the control signal into actuator position and valve opening accordingly.
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| == Three-way and four-way ball valves ==
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| [[Image:3-way.svg|120px|thumb|right|Schematic 3 way ball valve: L-shaped ball right, T-shaped left]]
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| <span id="immutable link 3-way from Valve"/> Three-way ball valves have an L- or T-shaped hole through the middle. The different combinations of flow are shown in the figure. It is easy to see that a T valve can connect any pair of ports, or all three, together, but the 45 degree position which might disconnect all three leaves no margin for error. The L valve can connect the center port to either side port, or disconnect all three, but it cannot connect the side ports together.
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| Multi-port ball valves with 4 ways, or more, are also commercially available, the inlet way often being orthogonal to the plane of the outlets. For special applications, such as driving air-powered motors from forward to reverse, the operation is performed by rotating a single lever [[four-way valve]]. The 4-way ball valve has two L-shaped ports in the ball that do not interconnect, sometimes referred to as an "<big>×</big>" port.
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| Ball valves in sizes up to 2 inch generally come in single piece, two or three piece designs. One piece ball valves are almost always reduced bore, are relatively inexpensive and generally are throw-away. Two piece ball valves are generally slightly reduced (or standard) bore, they can be either throw-away or repairable. The 3 piece design allows for the center part of the valve containing the ball, stem & seats to be easily removed from the pipeline. This facilitates efficient cleaning of deposited sediments, replacement of seats and gland packings, polishing out of small scratches on the ball, all this without removing the pipes from the valve body. The design concept of a three piece valve is for it to be repairable.
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| ==Images==
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| <gallery>
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| Image:Duplex-ball-valves-The-Alloy-Valve-Stockist-side.JPG|Super duplex ball valves
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| Image:Valve-balls-The-Alloy-Valve-Stockist.jpg|Balls for alloy ball valves
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| Image:Valve-nuts-bolts-The-Alloy-Valve-Stockist.jpg|Nuts and bolts for incoloy valves
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| Image:Ball-valve-ball-The-Alloy-Valve-Stockist.jpg|Ball for a titanium ball valve
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| Image:Double_block_and_bleed_ball_valve--The-Alloy-Valve-Stockist.JPG|Double block and bleed ball valve
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| File:Esquema valvula de bola.jpg|purple: disc, pink: seat, green: stem, blue: bonnet, red: lever
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| </gallery>
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| [[File:Ball valve, ball valve valve.jpg|thumb|Assorted ball valves]]
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| ==References==
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| {{reflist}}
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| ==See also==
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| {{Commons category|ball valves|ball valve|position=left}}
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| * [[Butterfly valve]]
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| * [[Control valve]]
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| * [[Gate valve]]
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| * [[Globe valve]]
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| * [[Piston Valve]]
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| * [[Hydrogen valve]]
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| * [[Plastic pressure pipe systems]]
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| * [[Needle valve]]
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| * [[Thermal Expansion]]
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| * [[Pinch valve]]
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| [[Category:Plumbing valves]]
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| [[Category:Valves]]
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The author is known by the url of Latoria. Puerto Rico exactly where her home is. Auditing is how he supports his loved one. It's not a known thing but what she likes doing is lacemaking but she has been taking on new things lately. Check out my website here: http://euroseonews.wordpress.com/