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searchaux" style="display:none">Type of valve with a small port</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Needle_valve" title="Special:EditPage/Needle valve">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Needle+valve%22">"Needle valve"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Needle+valve%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Needle+valve%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Needle+valve%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Needle+valve%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Needle+valve%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">December 2007</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Injector_Giffard-02.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/16/Injector_Giffard-02.jpg/220px-Injector_Giffard-02.jpg" decoding="async" width="220" height="131" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/16/Injector_Giffard-02.jpg/330px-Injector_Giffard-02.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/16/Injector_Giffard-02.jpg/440px-Injector_Giffard-02.jpg 2x" data-file-width="960" data-file-height="570" /></a><figcaption>Giffard steam water injector (B-needle valve).</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Needle_valve.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Needle_valve.jpg/220px-Needle_valve.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Needle_valve.jpg/330px-Needle_valve.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Needle_valve.jpg/440px-Needle_valve.jpg 2x" data-file-width="1280" data-file-height="960" /></a><figcaption>A needle valve.</figcaption></figure> <p>A <b>needle valve</b> is a type of <a href="/wiki/Valve" title="Valve">valve</a> with a small port and a <a href="/wiki/Screw_thread" title="Screw thread">threaded</a>, needle-shaped plunger. It allows <a href="https://en.wiktionary.org/wiki/precision" class="extiw" title="wikt:precision">precise</a> regulation of <a href="/wiki/Fluid_dynamics" title="Fluid dynamics">flow</a>, although it is generally only capable of relatively low flow rates. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Construction_and_operation">Construction and operation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Needle_valve&action=edit&section=1" title="Edit section: Construction and operation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An instrument needle valve uses a tapered pin to gradually open a space for fine control of flow. The flow can be controlled and regulated with the use of a spindle. A needle valve has a relatively small orifice with a long, tapered seat, and a needle-shaped plunger on the end of a screw, which exactly fits the seat. </p><p>As the screw is turned and the plunger retracted, flow between the seat and the plunger is possible; however, until the plunger is completely retracted, the fluid flow is significantly impeded. Since it takes many turns of the fine-threaded screw to retract the plunger, precise regulation of the flow rate is easily possible. </p><p>The virtue of the <b>needle valve</b> is from the <a href="/wiki/Vernier_scale" title="Vernier scale">vernier</a> effect of the ratio between the needle's length and its diameter, or the difference in diameter between needle and seat. A long travel axially (the control input) makes for a very small and precise change radially (affecting the resultant flow). </p><p>Needle valves may also be used in <a href="/wiki/Vacuum_system" class="mw-redirect" title="Vacuum system">vacuum systems</a>, when a precise control of gas flow is required, at low pressure,<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> such as when filling <a href="/wiki/Vacuum_tube#Special-purpose_tubes" title="Vacuum tube">gas-filled vacuum tubes</a>, <a href="/wiki/Gas_laser" title="Gas laser">gas lasers</a> and similar devices. </p> <div class="mw-heading mw-heading2"><h2 id="Uses">Uses</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Needle_valve&action=edit&section=2" title="Edit section: Uses"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Automated_needle_valve_with_electric_actuator.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/45/Automated_needle_valve_with_electric_actuator.jpg/220px-Automated_needle_valve_with_electric_actuator.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/45/Automated_needle_valve_with_electric_actuator.jpg/330px-Automated_needle_valve_with_electric_actuator.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/45/Automated_needle_valve_with_electric_actuator.jpg/440px-Automated_needle_valve_with_electric_actuator.jpg 2x" data-file-width="3000" data-file-height="2250" /></a><figcaption>Electrically automated needle valve fluid on a fluid processing system.</figcaption></figure> <p>Needle valves are usually used in flow-metering applications, especially when a constant, calibrated, low flow rate must be maintained for some time, such as the idle fuel flow in a <a href="/wiki/Carburettor" class="mw-redirect" title="Carburettor">carburettor</a>. </p> <dl><dd>Note that the <a href="/wiki/Float_chamber" title="Float chamber">float valve</a> of a carburettor (controlling the fuel level within the carburettor) is <i>not</i> a needle valve, although it is commonly described as one. It uses a bluntly conical needle, but it seats against a square-edged seat rather than a matching cone. The intention here is to obtain a well-defined seat between two narrow mating surfaces, giving firm shutoff of the flow from only a light float pressure.</dd></dl> <p>Needle valves are also commonly used to provide shut off for the pressure gauge or on applicators to shut off the supply of NH3 to the knives in <a href="/wiki/Anhydrous_ammonia" class="mw-redirect" title="Anhydrous ammonia">anhydrous ammonia</a> (NH3) applications.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>Since flow rates are low and many turns of the valve stem are required to completely open or close, needle valves are not used for simple shutoff applications. </p><p>Since the orifice is small and the force advantage of the fine-threaded stem is high, needle valves are usually easy to shut off completely, with merely "finger-tight" pressure. The spindle and/or seat of a needle valve, especially one made from <a href="/wiki/Brass" title="Brass">brass</a>, are easily damaged by excessive turning force when shutting off the flow. </p><p>Small, simple needle valves are often used as <a href="/wiki/Bleed_valve" class="mw-redirect" title="Bleed valve">bleed valves</a> in water-heating applications. </p><p>Unlike a <a href="/wiki/Ball_valve" title="Ball valve">ball valve</a> or valves with a rising stem, it is not easy to tell from examining the handle position whether the valve is open or closed. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Needle_valve&action=edit&section=3" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 23em;"> <ul><li><a href="/wiki/Ball_valve" title="Ball valve">Ball valve</a></li> <li><a href="/wiki/Butterfly_valve" title="Butterfly valve">Butterfly valve</a></li> <li><a href="/wiki/Control_valve" title="Control valve">Control valve</a></li> <li><a href="/wiki/Diaphragm_valve" title="Diaphragm valve">Diaphragm valve</a></li> <li><a href="/wiki/Flow_limiter" title="Flow limiter">Flow limiter</a></li> <li><a href="/wiki/Gate_valve" title="Gate valve">Gate valve</a></li> <li><a href="/wiki/Globe_valve" title="Globe valve">Globe valve</a></li> <li><a href="/wiki/Mass_flow_controller" title="Mass flow controller">Mass flow controller</a></li> <li><a href="/wiki/Plastic_pressure_pipe_systems" class="mw-redirect" title="Plastic pressure pipe systems">Plastic pressure pipe systems</a></li> <li><a href="/wiki/Plug_valve" title="Plug valve">Plug valve</a></li></ul> </div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Needle_valve&action=edit&section=4" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-lower-roman"> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFWardBunn1967" class="citation book cs1">Ward, L.; Bunn, J.P. (1967). <i>Introduction to the Theory and Practice of High Vacuum Technology</i>. Butterworths. pp. 125–126.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Introduction+to+the+Theory+and+Practice+of+High+Vacuum+Technology&rft.pages=125-126&rft.pub=Butterworths&rft.date=1967&rft.aulast=Ward&rft.aufirst=L.&rft.au=Bunn%2C+J.P.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANeedle+valve" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.continentalnh3.com/needle-valves.html">"NH3 (Anhydrous Ammonia) Needle Valves"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=NH3+%28Anhydrous+Ammonia%29+Needle+Valves&rft_id=http%3A%2F%2Fwww.continentalnh3.com%2Fneedle-valves.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ANeedle+valve" class="Z3988"></span></span> </li> </ol></div></div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul 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pipe</a></li> <li><a href="/wiki/Tube_bending" title="Tube bending">Tube bending</a></li> <li><a href="/wiki/Water_heat_recycling" title="Water heat recycling">Water heat recycling</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Components</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Atmospheric_vacuum_breaker" title="Atmospheric vacuum breaker">Atmospheric vacuum breaker</a></li> <li><a href="/wiki/Automatic_bleeding_valve" title="Automatic bleeding valve">Automatic bleeding valve</a></li> <li><a href="/wiki/Automatic_faucet" title="Automatic faucet">Automatic faucet</a></li> <li><a href="/wiki/Backflow_prevention_device" title="Backflow prevention device">Backflow prevention device</a></li> <li><a href="/wiki/Ball_valve" title="Ball valve">Ball valve</a></li> <li><a href="/wiki/Bleed_screw" title="Bleed screw">Bleed screw</a></li> <li><a href="/wiki/Booster_pump" title="Booster pump">Booster pump</a></li> <li><a href="/wiki/Butterfly_valve" title="Butterfly valve">Butterfly valve</a></li> <li><a href="/wiki/Check_valve" title="Check valve">Check valve</a></li> <li><a href="/wiki/Chemigation_valve" title="Chemigation valve">Chemigation valve</a></li> <li><a href="/wiki/Chopper_pump" class="mw-redirect" title="Chopper pump">Chopper pump</a></li> <li><a href="/wiki/Circulator_pump" title="Circulator pump">Circulator pump</a></li> <li><a href="/wiki/Cistern" title="Cistern">Cistern</a></li> <li><a href="/wiki/Closet_flange" title="Closet flange">Closet flange</a></li> <li><a href="/wiki/Concentric_reducer" title="Concentric reducer">Concentric reducer</a></li> <li><a href="/wiki/Condensate_pump" title="Condensate pump">Condensate pump</a></li> <li><a href="/wiki/Coupling_(piping)" title="Coupling (piping)">Coupling (piping)</a></li> <li><a href="/wiki/Diaphragm_valve" title="Diaphragm valve">Diaphragm valve</a></li> <li><a href="/wiki/Dielectric_union" class="mw-redirect" title="Dielectric union">Dielectric union</a></li> <li><a href="/wiki/Double_check_valve" title="Double check valve">Double check valve</a></li> <li><a href="/wiki/Eccentric_reducer" title="Eccentric reducer">Eccentric reducer</a></li> <li><a href="/wiki/Expansion_tank" title="Expansion tank">Expansion tank</a></li> <li><a href="/wiki/Faucet_aerator" title="Faucet aerator">Faucet aerator</a></li> <li><a href="/wiki/Float_switch" title="Float switch">Float switch</a></li> <li><a href="/wiki/Float_valve" class="mw-redirect" title="Float valve">Float valve</a></li> <li><a href="/wiki/Floor_drain" title="Floor drain">Floor drain</a></li> <li><a href="/wiki/Flow_limiter" title="Flow limiter">Flow limiter</a></li> <li><a href="/wiki/Flushing_trough" title="Flushing trough">Flushing trough</a></li> <li><a href="/wiki/Flushometer" title="Flushometer">Flushometer</a></li> <li><a href="/wiki/Gate_valve" title="Gate valve">Gate valve</a></li> <li><a href="/wiki/Globe_valve" title="Globe valve">Globe valve</a></li> <li><a href="/wiki/Grease_trap" title="Grease trap">Grease trap</a></li> <li><a href="/wiki/Grinder_pump" title="Grinder pump">Grinder pump</a></li> <li><a href="/wiki/Hose_coupling" title="Hose coupling">Hose coupling</a></li> <li><a href="/wiki/Manifold_(fluid_mechanics)" title="Manifold (fluid mechanics)">Manifold</a></li> <li><a class="mw-selflink selflink">Needle valve</a></li> <li><a href="/wiki/Nipple_(plumbing)" title="Nipple (plumbing)">Nipple (plumbing)</a></li> <li><a href="/wiki/Pinch_valve" title="Pinch valve">Pinch valve</a></li> <li><a href="/wiki/Piping_and_plumbing_fitting" title="Piping and plumbing fitting">Piping and plumbing fitting</a></li> <li><a href="/wiki/Plug_(sanitation)" title="Plug (sanitation)">Plug (sanitation)</a></li> <li><a href="/wiki/Pressure_regulator" title="Pressure regulator">Pressure regulator</a></li> <li><a href="/wiki/Pressure_vacuum_breaker" title="Pressure vacuum breaker">Pressure vacuum breaker</a></li> <li><a href="/wiki/Pressure-balanced_valve" title="Pressure-balanced valve">Pressure-balanced valve</a></li> <li><a href="/wiki/Pump" title="Pump">Pump</a></li> <li><a href="/wiki/Radiator_(heating)" title="Radiator (heating)">Radiator (heating)</a></li> <li><a href="/wiki/Reduced_pressure_zone_device" title="Reduced pressure zone device">Reduced pressure zone device</a></li> <li><a href="/wiki/Reducer" class="mw-redirect" title="Reducer">Reducer</a></li> <li><a href="/wiki/Relief_valve" title="Relief valve">Relief valve</a></li> <li><a href="/wiki/Riser_clamp" title="Riser clamp">Riser clamp</a></li> <li><a href="/wiki/Rooftop_water_tower" title="Rooftop water tower">Rooftop water tower</a></li> <li><a href="/wiki/Safety_valve" title="Safety valve">Safety valve</a></li> <li><a href="/wiki/Sewage_pump" class="mw-redirect" title="Sewage pump">Sewage pump</a></li> <li><a href="/wiki/Street_elbow" title="Street elbow">Street elbow</a></li> <li><a href="/wiki/Submersible_pump" title="Submersible pump">Submersible pump</a></li> <li><a href="/wiki/Tap_(valve)" title="Tap (valve)">Tap (valve)</a></li> <li><a href="/wiki/Thermostatic_mixing_valve" title="Thermostatic mixing valve">Thermostatic mixing valve</a></li> <li><a href="/wiki/Trench_drain" title="Trench drain">Trench drain</a></li> <li><a href="/wiki/Vacuum_breaker" title="Vacuum breaker">Vacuum breaker</a></li> <li><a href="/wiki/Vacuum_ejector" title="Vacuum ejector">Vacuum ejector</a></li> <li><a href="/wiki/Valve" title="Valve">Valve</a></li> <li><a href="/wiki/Water_tank" title="Water tank">Water tank</a></li> <li><a href="/wiki/Zone_valve" title="Zone valve">Zone valve</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Plumbing_fixture" title="Plumbing fixture">Plumbing fixtures</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Accessible_bathtub" title="Accessible bathtub">Accessible bathtub</a></li> <li><a href="/wiki/Bathtub" title="Bathtub">Bathtub</a></li> <li><a href="/wiki/Bidet" title="Bidet">Bidet</a></li> <li><a href="/wiki/Dehumidifier" title="Dehumidifier">Dehumidifier</a></li> <li><a href="/wiki/Dishwasher" title="Dishwasher">Dishwasher</a></li> <li><a href="/wiki/Drinking_fountain" title="Drinking fountain">Drinking fountain</a></li> <li><a href="/wiki/Electric_water_boiler" title="Electric water boiler">Electric water boiler</a></li> <li><a href="/wiki/Evaporative_cooler" title="Evaporative cooler">Evaporative cooler</a></li> <li><a href="/wiki/Flush_toilet" title="Flush toilet">Flush toilet</a></li> <li><a href="/wiki/Garbage_disposal_unit" title="Garbage disposal unit">Garbage disposal unit</a></li> <li><a href="/wiki/Hot_water_storage_tank" title="Hot water storage tank">Hot water storage tank</a></li> <li><a href="/wiki/Humidifier" title="Humidifier">Humidifier</a></li> <li><a href="/wiki/Icemaker" title="Icemaker">Icemaker</a></li> <li><a href="/wiki/Instant_hot_water_dispenser" title="Instant hot water dispenser">Instant hot water dispenser</a></li> <li><a href="/wiki/Laundry_tub" class="mw-redirect" title="Laundry tub">Laundry tub</a></li> <li><a href="/wiki/Shower" title="Shower">Shower</a> <ul><li><a href="/wiki/Water_recycling_shower" title="Water recycling shower">water recycling shower</a></li></ul></li> <li><a href="/wiki/Sink" title="Sink">Sink</a></li> <li><a href="/wiki/Storage_water_heater" title="Storage water heater">Storage water heater</a></li> <li><a href="/wiki/Sump_pump" title="Sump pump">Sump pump</a></li> <li><a href="/wiki/Tankless_water_heater" class="mw-redirect" title="Tankless water heater">Tankless water heater</a></li> <li><a href="/wiki/Urinal" title="Urinal">Urinal</a></li> <li><a href="/wiki/Washing_machine" title="Washing machine">Washing machine</a></li> <li><a href="/wiki/Washlet" title="Washlet">Washlet</a></li> <li><a href="/wiki/Water_dispenser" title="Water dispenser">Water dispenser</a></li> <li><a href="/wiki/Water_filter" title="Water filter">Water filter</a></li> <li><a href="/wiki/Water_heater" class="mw-redirect" title="Water heater">Water heater</a></li> <li><a href="/wiki/Water_softener" class="mw-redirect" title="Water softener">Water softener</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Specialized tools</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Basin_wrench" title="Basin wrench">Basin wrench</a></li> <li><a href="/wiki/Blowtorch" title="Blowtorch">Blowtorch</a></li> <li><a href="/wiki/Borescope" title="Borescope">Borescope</a></li> <li><a href="/wiki/Core_drill" title="Core drill">Core drill</a></li> <li><a href="/wiki/Drain_cleaner" title="Drain cleaner">Drain cleaner</a></li> <li><a href="/wiki/Driving_cap" title="Driving cap">Driving cap</a></li> <li><a href="/wiki/Flare-nut_wrench" class="mw-redirect" title="Flare-nut wrench">Flare-nut wrench</a></li> <li><a href="/wiki/Pipecutter" title="Pipecutter">Pipecutter</a></li> <li><a href="/wiki/Pipe_wrench" title="Pipe wrench">Pipe wrench</a></li> <li><a href="/wiki/Plumber%27s_snake" title="Plumber's snake">Plumber's snake</a></li> <li><a href="/wiki/Plumber_wrench" title="Plumber wrench">Plumber wrench</a></li> <li><a href="/wiki/Plunger" title="Plunger">Plunger</a></li> <li><a href="/wiki/Strap_wrench" title="Strap wrench">Strap wrench</a></li> <li><a href="/wiki/Tap_and_die" title="Tap and die">Tap and die</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Measurement<br />and control</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Control_valve" title="Control valve">Control valve</a></li> <li><a href="/wiki/Flow_sensor" class="mw-redirect" title="Flow sensor">Flow sensor</a></li> <li><a href="/wiki/Pressure_sensor" class="mw-redirect" title="Pressure sensor">Pressure sensor</a></li> <li><a href="/wiki/Water_detector" title="Water detector">Water detector</a></li> <li><a href="/wiki/Water_metering" title="Water metering">Water metering</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Professions,<br />trades,<br />and services</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hydronic_balancing" title="Hydronic balancing">Hydronic balancing</a></li> <li><a href="/wiki/Hydrostatic_testing" class="mw-redirect" title="Hydrostatic testing">Hydrostatic testing</a></li> <li><a href="/wiki/Leak_detection" title="Leak detection">Leak detection</a></li> <li><a href="/wiki/Mechanical,_electrical,_and_plumbing" title="Mechanical, electrical, and plumbing">Mechanical, electrical, and plumbing</a></li> <li><a href="/wiki/Pipe_marking" title="Pipe marking">Pipe marking</a></li> <li><a href="/wiki/Pipefitter" title="Pipefitter">Pipefitter</a></li> <li><a href="/wiki/Pipelayer" title="Pipelayer">Pipelayer</a></li> <li><a href="/wiki/Plumber" title="Plumber">Plumber</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Industry <br />organizations <br />and standards</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/International_Association_of_Plumbing_and_Mechanical_Officials" class="mw-redirect" title="International Association of Plumbing and Mechanical Officials">International Association of Plumbing and Mechanical Officials (IAPMO)</a></li> <li><a href="/wiki/NSF_International" title="NSF International">NSF International</a></li> <li><a href="/wiki/Plumbing_%26_Drainage_Institute" title="Plumbing & Drainage Institute">Plumbing & Drainage Institute (PDI)</a></li> <li><a href="/wiki/Uniform_Plumbing_Code" title="Uniform Plumbing Code">Uniform Plumbing Code (UPC)</a></li> <li><a href="/wiki/World_Plumbing_Council" title="World Plumbing Council">World Plumbing Council (WPC)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Health and safety</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Plumbing_code" title="Plumbing code">Plumbing code</a></li> <li><a href="/wiki/Scalding" title="Scalding">Scalding</a></li> <li><a href="/wiki/Waterborne_disease" title="Waterborne disease">Waterborne disease</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">See also</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0;text-align: middle;"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fire_sprinkler_system" title="Fire sprinkler system">Fire sprinkler system</a></li> <li><a href="/wiki/Piping" title="Piping">Piping</a></li> <li><a href="/wiki/Template:HVAC" title="Template:HVAC">Template:HVAC</a></li> <li><a href="/wiki/Template:Public_health" title="Template:Public health">Template:Public health</a></li> <li><a href="/wiki/Template:Sewerage" title="Template:Sewerage">Template:Sewerage</a></li> <li><a href="/wiki/Template:Toilets" class="mw-redirect" title="Template:Toilets">Template:Toilets</a></li> <li><a href="/wiki/Template:Wastewater" title="Template:Wastewater">Template:Wastewater</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" 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