Funnel

Design and common parts

Most funnels have two primary parts: the bowl (the wide section that collects material) and the stem (the narrow tube that directs flow). Variations add features such as a short or long stem, a vent or side tube to prevent glugging, graduations for measuring, or a built-in filter support for paper or mesh.

Materials and typical varieties

• Plastic: lightweight, inexpensive, used for household and automotive tasks.
• Glass: common in chemistry labs for cleanliness and chemical resistance.
• Metal: durable for industrial and kitchen use.
• Silicone and collapsible models: space-saving for camping and travel.

Uses and examples

Funnels appear in kitchens for pouring oil, in vehicles for adding fluids, and in laboratories as filter funnels, separatory funnels and Buchner funnels for chemical separations. Industry uses large cone-shaped hoppers and chutes that operate on the same principle. The word has also been adopted metaphorically (for example, a "sales funnel") to describe staged narrowing processes.

History and notable facts

The funnel's simple form has been used for centuries wherever controlled transfer of liquids or powders is needed. The English name derives from older Germanic languages; in maritime contexts "funnel" commonly refers to a vessel's smokestack, a prominent visual feature used to vent boiler gases.

Distinctions

Not every tapered container is a funnel: hoppers and chutes are larger handling devices, while specialized laboratory funnels are defined by intended function (e.g., filtration vs liquid-liquid separation). Choosing a funnel depends on compatibility with the material, required flow rate, and the receiver's opening.