Rod mill
Rod mill introduced
The rod mill is a mill, the grinding media are steel bars, cylinder form is cylindrical, the quintana length / diameter ratio between 1.3 to 2.6, its ways of discharge is the overflow type surrounding open-type wind, the transmission mode to take a peripheral gear drive and friction drive in two ways, cylinder support in three ways: bearing support, roller support, mixed support, the general direction of the application of various industrial sectors.
Rod mill Classification
The wet rod mill can be divided into a nesting overflow type openings in and around the three, the overflow type. The opening rod mill row of ore speed faster product coarse grain size, had crushed a lesser degree; peripheral-type row of mine mill feed both ends of discharge faster product granularity is more coarse.
The dry rod mill using wind nesting, but the general domestic production of this mill. Rod mill overflow structure and overflow ball mill, the difference is the curvature of the conical end caps of the rod mill, inner side equipped with a smooth lining, while the cylinder on the general use of smooth liner; row mine hollow shaft diameter. The steel bar mill rules of exercise does not occur skew, and therefore would not fight against each other in the whereabouts of bending; larger diameter of discharge port in order to facilitate the loaded rod and into the maintenance and inspection, but also to reduce the slurry level , so that the slurry can be quickly discharged. The rod mill speed is low, medium filling rate is low, about -40%. Feed size is generally 25 ~ 30mm over the General Assembly to make steel bars skew, the operation will cause the steel bars bent and broken; the same time, the nugget of the General Assembly, there are large gaps between bars and difficult to grind to a fine-grained, causing output to fall. Ore by the steel bars falling "line contact" to be crushed and ground, stick stamping before the chunk is not broken, fine rarely, and thus been crush phenomenon, more uniform product granularity, usually a ~ 3mm.
The characteristics of a rod mill
(1) the structure of the rod mill and ball mill is basically the same, the difference is that the former is the cylinder length to diameter ratio (LID) larger, generally 1.5 to 2.0. Row of ore client does not have exclusive mineral lattice board, port of discharge Overflow Ball Mill for successful nesting, loading the rod and remove the broken rods and curved rods. Chaotic stick phenomenon, in order to prevent the cylinder rotating steel bar skew and conical end caps of the rod mill before putting the lining of the inner surface is flat. It is based on the round steel bar as the grinding media, grinding equipment, and its length is generally shorter than the length of the cylinder about 100 ~ 150 mm in diameter is generally 60 to 120 mm, steel bars are too thick to easily smashed mill lining too thin wear and easy to break.
(2) operation of the rod mill line of contact between the rods and bars, rods and materials, so the grinding "effect, uniform particle size, generally 1 to 3 mm in the material had crushed a lesser degree. Rod accumulation in the cylinder stationary bulk density of 1.36 times the ball medium of the same material, so the rod mill media filling rate is low, typically 30% to 35%, the transfer rate is also lower, typically 60% ~ 75%. Should not be greater than 25 mm feed size, otherwise it would stick to produce skewed work causes the rod bend and break, so that the grinding effect of deterioration.
(3) rod dielectric rod medium to add a plus rod machine, production should be regularly wear Stick media parking inspection machines, at any time taken out for the broken and bent rod media, so as not to interfere with the normal finished Haobang media work. Rod mill operating rate is low, generally 80% to 88%.
The use of a rod mill
Used for processing brittle materials such as tungsten, tin re-election; also be used for the pretreatment of the ball mill feed for the open-circuit grinding in order to reduce the granularity of the ball mill feed.