View source for Funnel

{{Short description|Pipe with a wide top and narrow bottom}}
{{Other uses}}
[[File:Kitchen Funnel.jpg|thumb|A typical kitchen funnel]]
[[File:Roman Kitchen Funnel Saalburg.jpg|thumb|A ceramic [[Ancient Rome|Roman]] kitchen funnel (1st–3rd century AD)]]
A '''funnel''' is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening.
Funnels are usually made of [[stainless steel]], [[aluminium]], [[glass]], or [[plastic]]. The material used in its construction should be sturdy enough to withstand the weight of the substance being transferred, and it should not react with the substance. For this reason, stainless steel or glass are useful in transferring [[Diesel fuel]], while plastic funnels are useful in the kitchen. Sometimes disposable [[paper]] funnels are used in cases where it would be difficult to adequately clean the funnel afterwards (for example, in adding [[motor oil]] into a car). Dropper funnels, also called [[dropping funnels]] or tap funnels, have a [[Tap (valve)|tap]] to allow the controlled release of a liquid. A flat funnel,<ref>
{{Cite web |url= http://www.flatfunnel.com
|title= Flat Funnel for Compact Storage in kitchen garage RV to funnel fluids
|website= Flat Funnel
|access-date= 2016-06-09
|url-status= dead
|archive-url= https://web.archive.org/web/20160528203254/http://www.flatfunnel.com/
|archive-date= 2016-05-28 }}
</ref> made of polypropylene, utilises [[living hinge]]s and flexible walls to fold flat.
The term "funnel" may refer to the [[Chimney (locomotive)|chimney or smokestack]] on a steam [[locomotive]] and commonly refers to [[funnel (ship)|the same on a ship]]. The term ''funnel'' is also applied to other seemingly strange objects like a [[Smoking pipe (tobacco)|smoking pipe]] or a kitchen [[Wastebin|bin]].
==Laboratory funnels==
{{main|Laboratory funnel}}
<!-- [[File:FilterFunnelApparatus.png|thumb|upright|A Büchner funnel with a sintered glass disc]] -->
There are many different kinds of funnels that have been adapted for specialised applications in the laboratory, such as [[Filter funnel]]s and [[thistle funnel]]s (shaped like [[thistle]] flowers). [[Dropping funnel]]s have stopcocks which allow the fluids to be added to a flask slowly. For solids, a powder funnel with a wide and short stem is more appropriate as it does not clog easily.
When used with [[filter paper]], filter funnels, [[Büchner funnel|Büchner]] and [[Hirsch funnel]]s can be used to remove fine particles from a liquid in a process called [[filtration]]. For more demanding applications, the filter paper in the latter two may be replaced with a sintered glass frit. [[Separatory funnel]]s are used in [[liquid-liquid extraction]]s. The [[Tullgren funnel]] is used to collect [[arthropod]]s from [[plant litter]] or similar material.<ref name="dicent">{{cite book |title=A Dictionary of Entomology |year=2011 |publisher=CABI |isbn=978-1845935429 |page=172 |url=https://books.google.com/books?id=9IcmCeAjp6cC |access-date=9 July 2013}}</ref>
=== Construction ===
Glass is the material of choice for laboratory applications due to its inertness compared with metals or plastics. However, plastic funnels made of nonreactive [[polyethylene]] are used for transferring aqueous solutions. Plastic is most often used for powder funnels that do not come into contact with solvent in normal use.
=== Uses ===
* To channel [[liquids]] or fine-grained substances into containers with a small opening. Used for pouring liquids or powder through a small opening and for holding the filter paper in filtration. Used in transferring liquids in small containers.
* Funnels known as [[killing cone]]s are used to slaughter individual birds in [[poultry farming]]. The funnel is used to hold a bird upside down so that it can be bled more easily.<ref>Sparrey, J., SandercockD., Sparks, N., & Sandilands, V. (2014). Current and novel methods for killing poultry individually on-farm. ''World's Poultry Science Journal,'' ''70''(4), 737-758. doi:10.1017/S0043933914000816</ref>
== See also ==
* [[Funneling (disambiguation)]]
* [[Tundish]], used in [[plumbing]] and [[continuous casting]]
==References==
{{Reflist}}
==External links==
{{Wiktionary|funnel}}
* {{Commons category-inline|Funnel shaped objects}}
* {{Commons category-inline|Funnels (ship part)}}
{{Hand tools}}
{{Kitchen tools}}
{{Laboratory equipment}}
[[Category:Food preparation utensils]]
[[Category:Laboratory glassware]]