Stone roller

Numerous kinds of mechanical adaptations have been introduced into this department varying in simplicity from Hie old head-stone rollers, to very intricate ar-... 

Burr stones, roller mills, cha.ser mills, pebble mills, and mills having antagoniz-... 

Also Mix-Muller. Originally, a device that used a heavy stone roller to grind and/or mix particulate solids. Today, a blender with one, two or four large metal rollers that mix and knead (densify) material. Often used prior to pressure agglomeration. (See also pan grinder.)... 

In a roller mill wholemeal flour can only be made by recombining all the fractions at the bottom of the mill. This is why some wholemeal flour is still stone ground. The stone mills used are not antiques but are usually driven by electricity. There is no reason why roller mills or stone mills should not be driven by water power in the form of a water turbine. 

A machine for the comminution, or size reduction, of mineral lumps or stones. Such machines crush the input material between a plate and revolving roller or between more than one roller. 

The fourth physical characteristic of Chinese silks, a soft "hand , we feel is the result of calendering, which is a characteristic mechanical method for finishing silks in China (Figure 3). This process involves a stone base plate, a wooden roller, and a heavy rocking stone. The silk fabric is placed on a roller and subjected to intense pressure as a workman rocks back and forth on a rocking stone. This process leaves an unmistakable sheen and soft clinging hand that can distinguish Chinese silks from Western ones. 

Scarab beetles, Scarabaeus sacer, also known as dung rollers, are indigenous to Egypt, where they were regarded as sacred in ancient times, and whole beetles were mummified. This was still being done as recently as the 1950s, and the beetles sold as jewellery. Today they are copied in carved stone. 

Before mixing, materials are prepared, i.e. coarse grains are finely ground in a mill, wooden roller or ball mill etc. Fob potassium nitrate or barium nitrate a wooden roller will do. But hard stone-like masses need to be ground in a suitable machine. Each of the materials should be passed once through the sieve in order to make the mesh size uniform and to remove foreign substances. In practice it is common to find unexpected matter nails, pieces of metal, sand etc. which are present in the materials even though they look as if they are pure. 

Mortar and pestles Grunding stones Cutter mills Sieves and screens Roller mills... 

The one-roll mill works on a similar principle but the nip is regulated by a pressure bar. Shearing takes plaee between the roller and the shearing bar. Stone mills have similar prineiples of operation. The rotor turns on a stator to achieve shearing... 

Hemp is retted in water tanks in a manner similar to flax, after which the stalks are laid out to dry. The fibres are then separated either manually or mechanically by passing through fluted rollers which crush the woody tissues. At this state the hemp is softened by beating with a softwood mallet on a flat stone or a hard floor. The same effect can also be achieved when a heavy millstone, usually operated by water power, rolls over the fibres for 3 or 4 hours. Finally the fibres, which tend to stick together, are separated by combing. 

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