The rod mill does not use the grid plate to discharge ore, but uses the overflow type and the open type to discharge the ore; the hollow shaft journal of the discharge end is generally larger than the ball mill of the same specification. The rotation speed of the rod mill cylinder should be lower than the working speed of the same size ball mill , so that the medium inside is in the sloping state.

The lining of the rod mill is mostly waved, stepped or wedge shaped. Depending on the method of mine discharge, the rod mill can be divided into a central discharge type (overflow type) and a peripheral discharge type (open type). The former is widely used and the latter has stopped manufacturing. Figure 6-8 shows the structure of the overflow rod mill. It can be seen from the figure that the diameter of the hollow journal of the discharge end is much larger than that of the overflow ball mill of the same specification, in order to reduce the level of the slurry and accelerate the speed of the slurry through the rod mill. The large rod mill has a discharge opening of up to 1200mm.

The rod mill grinds the ore according to the pressure of the rod and the peeling force. When the rod hits the ore, the first is to break the coarse particles, and then grind the smaller ore; the rod is in contact with the rod, and the ball is in point contact with the ball, so when the rod rotates along the barrel wall When it rises, it is sandwiched between coarse particles and acts like a bar sieve to allow fine particles to pass between the joints. This also helps to crush the coarse particles and concentrate the coarse particles in the place where the grinding media strikes. Therefore, the rod ball mill has selective grinding action, and the product has a uniform particle size and less pulverization.

Rod mills usually use steel rods with a diameter of 50~100mm as the grinding medium, while rod mills use steel balls as the grinding medium. The length of the steel rod is 25~50mm shorter than that of the cylinder. It is usually made of high carbon steel with 0.8%~1% carbon. The loading of the rod is about 35%~45% of the effective volume of the rod ball mill. When observed with the naked eye, The horizontal plane of the rod is about 100~200mm below the centerline of the cylinder. The ratio of the length of the rod mill to the diameter is generally 1.5 to 2.0, and the inner surface of the liner on the end cap should be a vertical plane. The purpose is to prevent and reduce the chaotic movement, bending and breaking of the steel rod in the cylinder to ensure that the steel rod moves regularly. The ratio of the barrel length to the diameter of the ball mill is small, and in most cases the ratio is only slightly greater than one.

Manipulator Laser Welding Machine

Manipulator laser welding machine

Shenzhen You Kong Laser Technology Co., Ltd , https://www.youkonglaser.com