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The most familiar choke design is a solid cylinder (called a "plug" or "stem") that closely fits inside another cylinder that has multiple small holes through it (the "cage"). Gradually withdrawing the plug uncovers more and more holes, progressively reducing the resistance to flow. If the holes are
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Fluids flowing into the cage (through all uncovered holes) enter from all sides, producing fluid jets. The jets collide at the center of the cage cylinder, dissipating most of their energy through fluid impinging on fluid, producing less friction and cavitation erosion of the metal valve body. For
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engines because small droplets of gasoline do not evaporate well within a cold engine. By restricting the flow of air into the throat of the carburetor, the choke valve reduces the pressure inside the throat, which causes a proportionally greater amount of fuel to be pushed from the main
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have "chokes" that work by lowering the fuel jet to a narrower part of the needle. Some others work by introducing an additional fuel route to the constant depression chamber.
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while starting the engine. Depending on engine design and application, the valve can be activated manually by the operator of the engine (via a
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began to supplant carburetors. Choke valves are still common in other internal-combustion engines, including most small portable engines,
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The term "choke" is applied to the carburetor's enrichment device even when it works by a totally different method. Commonly,
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A choke valve is sometimes installed in the carburetor of internal combustion engines. Its purpose is to restrict the flow of
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Internal
Combustion Engine in Theory and Practice, second edition, revised, Volume 2: Combustion, Fuels, Materials, Design
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mounted upstream of the carburetor jet to produce a higher partial vacuum, which increases the fuel draw.
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engines to supply a richer fuel mixture when starting the engine. Most choke valves in engines are
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Valve used to control the air pressure in the intake manifold of an internal combustion engine
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into the combustion chamber during cold-running operation. Once the engine is warm (from
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In heavy industrial or fluid engineering contexts, including oil and gas production, a
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regularly placed, then the relationship between the position of the valve and the
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Cross-sectional schematic of a basic carburetor, showing the choke valve at top
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with a solid cylinder placed inside another slotted or perforated cylinder.
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Short video of a choke valve operating on a chainsaw carburetor
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highly erosive or corrosive fluids, chokes can be made of
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383:(and other heavy-duty fluid handling contexts), a choke
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entering the engine. Choke valves are generally used in
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310:-sensitive mechanism called an automatic choke.
175:The examples and perspective in this article
486:Mokveld Product animation: axial choke valve
475:Mokveld Product animation: angle choke valve
53:Learn how and when to remove these messages
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216:Learn how and when to remove this message
150:Learn how and when to remove this message
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391:that is designed to operate at a large
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448:Taylor, Charles Fayette (1985-03-19).
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306:or pull handle) or automatically by a
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369:lawn mowers
361:motorcycles
353:automobiles
308:temperature
268:choke valve
234:carburetors
140:August 2022
525:Categories
435:References
375:Industrial
324:combustion
282:Carburetor
199:April 2019
110:newspapers
39:improve it
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397:flow rate
367:, riding
365:airplanes
191:talk page
179:full view
45:talk page
405:wellhead
315:gasoline
429:inconel
379:In the
185:Please
124:scholar
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232:with
131:JSTOR
117:books
456:ISBN
236:, a
103:news
427:or
320:jet
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