Revolving Screens or Trommels

Rotary sifters are of either gyratory or reciprocating types. They operate at 500-600 rpm and are used for sizes of 12 mm-50 pm, but have low capacity for fine sizes. 

TABLE 12.1. Comparison Table of United States, Tyler, Canadian, British, French, and German Standard Sieve Series 

---

Ordinary Revolving Screens or Trommels.— The most common type of those devices is of circular section, the screen cloth or plate being supported on spiders attached to a central shaft. This type of trommel has a slope of from a fraction of an inch to an inch and a half per foot, the tendency of late years being towards the higher figure of slope. Trommels are also made conical and pyramidal with horizontal supporting shafts. There is also a type which consists of a... 

Revolving screen Inclined trommel, scrubber, or barrel cylindrical, rotating wire cloth, and perforated plate 15-20 rpm open at ends Scrub, wash, rough size placer mining low capacity and efficiency... 

N F ievbivih< or th water filter screens and sewage screens Revolving screens trommels, scrubbe s ... 

Trommel. See revolving screen. Trompe I Oeil. Decoration, mainly applied as transfers, which deceives the eye to simulate e.g. bas-reliefs, or lustres to simulate silver or marble. 

---