Wet ball mill Introduction

Wet ball mill is a kind of ball mill. Ball mill can be divided into dry ball mill and wet ball mill. Wet ball mill needs to add water during the grinding process. Wet ball mill can be divided into two types according to its internal structure, one is overflow ball mill and the other is lattice/grid ball mill. The wet ball mill has the characteristics of high efficiency and energy saving. Because it adopts the wet grinding method, the material can be fully moistened, reducing the generation of dust. At the same time, the friction between the grinding steel ball and the grinding cylinder of the wet ball mill is relatively small, and the energy utilization rate is high, so the energy consumption is low. Tongli offers various specifications and models of Wet ball mill suitable for various ores such as gold ore, iron ore, copper ore, pyrrhotite, quartzite, bauxite, bluestone, kaolin, lithium ore (spodumene, lepidolite), calcite, magnesite, quartz sand, water slag, slag, glass, barite, potassium feldspar, alumina, granite, clinker, bauxite, etc.

Wet  ball mill structure

Mill Shell: The foundation of the wet ball mill, the mill shell, is a cylindrical structure made of premium-grade steel. Tongli heavy machinery is equipped with a large annealing furnace of 6.5x6.5x20m and a 6.5x6.5x20m large sandblasting room, which can conduct overall heat treatment and sandblasting on the ball mill to ensure the service life and appearance of the ball mill.

Trunnion: The trunnion (hollow shaft) of the wet ball mill is a steel casting manufactured in our metal casting workshop. It mainly plays the role of supporting and connecting the shell, it is the passage for the material to enter and exit. When the ball mill is operating, the trunnion is floating on the bearing bush with the aid of the forced high pressure lubrication system.

Bearing Bush: Wet ball mill bearing bush ensures the smooth rotation of the ball mill and empowers the ball mill to maintain optimal grinding conditions. It is equipped with a forced lubrication system and also cooling system. It has alloy surface and 3 rolling rods on the bottom to make sure when the ball mill trunnion moves, the position of the bearing bush can be adjustable.

Transmission connection: Tongli’s wet ball mill is equipped with a transmission connection, which is welded on the cylinder and machined together with the ball mill shell on our 5x18m CNC controlled horizontal lathe to avoid assembly errors and ensure the concentricity of the ball mill.

Hood Cover: The discharge hood of the wet ball mill is installed at the discharge end of the ball mill, and there is a screen inside. After grinding, the material with a qualified size will enter the discharge hood through the screen and enter the next process. There is a vent on the upper part of the discharge hood, and a discharge funnel on the lower part.

Diaphragm: The wet ball mill Diaphragm (compartment plate) is fan-shaped plate or bow-shaped grate plate fixed in the wet ball mill with bolts. Its function is to divide the ball mill into two or more chambers, the material moves to the next compartment through the openings on the grate plate. The function of the compartment plate is to prevent the grinding media running from one compartment to another compartment, so that the materials can be reasonably finely ground.

Liner: The function of the liner is to protect the shell of the ball mill and the trunnion, some special-shaped liners can also design to lift the grinding media to a certain position. According to the shape of the liner, it can be divided into flat liner, beaded liner, corrugated liner, ribbed liner, stepped liner, etc.

Over-flow ball mill transmission: Central drive ball mill refers to the arrangement of the driving mechanism for the mill. In a central drive configuration, the motor and gearbox are positioned at the center of the mill, usually between the grinding chamber and the mill shell. This design is in contrast to an edge or end drive configuration where the motor and gearbox are situated at one of the ends of the mill. Central drive transmission systems typically involve a motor that powers a gearbox, which then transfers the rotational energy to the mill's main shaft. The central drive design can provide advantages in terms of power distribution and efficiency compared to other drive arrangements. It can also offer better control over the mill's operation.

PLC control system: A PLC is a digital computer-based system that is designed to control various industrial processes automatically. In the context of a ball mill, a PLC is used to monitor and control parameters such as temperature, rotation speed, air flow, fuel flow, and other critical variables that affect the performance of the ball mill and the quality of the products being processed. 

Design principles of wet ball mill

The rotation motion of the Wet ball mill drives the internal steel balls or rods to squeeze the material to produce fine powder that meets the process requirements. The ball mill is composed of feeding part, discharging part, rotary part, transmission part and others.

The wet ball mill is equipped with a jacking device, which is convenient for maintenance and can be used for dry grinding or wet grinding with high efficiency. The inner lining of the overflow type ball mill shell is made of wear-resistant materials, so as to enhance the wear resistance and prolong the service life. The overflow ball mill equipment replaces the bush sliding bearing with rolling bearing, which not only saves energy but also reduces consumption.

Over flow wet ball mill: The discharge method adopted by the overflow wet ball mill is automatic discharge. Through continuous feeding, the finished product with qualified size in the mill overflows from the discharge end. This method makes the material fully ground, but also result in excessive grinding, the overflow ball mill is suitable for materials with high fineness requirements.

Grid type wet ball mill: Lattice ball mill is equipped with a forced discharge device at the discharge end, the grinding efficiency is high, and the residence time of the material in the mill is relatively short.

Advanced manufacturing Equipment: Tongli has over 100 set of large-scale mechanical processing equipment, especially a 5.3x18-meter fully numerically controlled horizontal lathe to ensure the processing accuracy and concentricity of the ball mill.

Heat treatment: Tongli heavy machinery is equipped with a large annealing furnace of 6.5x6.5x20m and a large sandblasting room, which can conduct overall heat treatment and sandblasting on the ball mill to ensure the service life and appearance of the ball mill.

Process Control: Tongli has its own metal casting foundry, starting from the raw material to the finished product, Quality in every detail, from start to finish.

Lubrication system: Tongli ball mill is equipped with force lubrication system, there is an oil station equipped for the transmission part, another oil station for the gearbox to ensure smooth operation and prolong service life of the ball mill.

Cooling system: The main bearing bush is equipped with a water cooling system, and a cooler is also installed in the lubrication system to forcibly cool the lubricating oil.

Transmission connection: Tongli’s ball mill is equipped with a transmission connection, which is welded on the cylinder and machined together with the ball mill shell to avoid assembly errors and ensure the concentricity of the ball mill.

Specifications of wet ball mill

Note: * Mill diameter refers to the inner diameter, while the mill length refers to the effective grinding length.

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Industry Knowledge extension

What is the advantage of wet ball mill?

Wet ball mill is a multifunctional equipment that can be applied to different types of material grinding. It can grind materials with various hardness, such as quartz stone, chalcopyrite, iron ore, metal ore and so on. At the same time, it can also grind materials of various viscosities, such as paints, paints, pigments, etc.When some materials are required by the technological process and have special requirements for fineness, then wet ball mills should be used for grinding, such as coal water slurry grinding. Dry ball mills, such as cement ball mill and coal ball mill, have strict requirements on the moisture content of the material. When the moisture content of the material is too high, it will be difficult to discharge and stick. In order to reduce the moisture, a hot blast stove must be added to reduce the moisture. The investment and production costs is higher. The wet ball mill can process ore with high moisture and clay content. When selecting low-grade magnetic iron ore, the wet ball mill can easily obtain any particle size required, and is suitable for magnetic separation. During the operation of the dry ball mill, the material layer will affect the energy consumption, while the wet ball mill will not, which is more energy-saving.

What is the difference between Open-circuit and closed-circuit ball mill?

Closed-circuit grinding refers to that in the grinding operation, the material is fed into the mill and then classified after one grinding, the ore with unqualified particle size is returned to the mill for regrinding, and the ore with qualified particle size is sent to the next stage. The closed-circuit mill has a high crushing rate, and the quality of the obtained product is high. At the same time, the output of the closed-circuit production is relatively large, but its disadvantage is that the production process is relatively complicated and the input cost is high.The production process of the open circuit mill is relatively simple, and the input cost is low. And its disadvantage is that it has low production efficiency, because the qualified fine powder cannot be removed in time, so it produces a large energy consumption during production.

What is the difference between ball mill and vertical roller mill?

Both ball mills and vertical roller mills plays a vital role in the cement grinding plant. Ball mills are versatile and cost-effective, suitable for various materials and simple to maintain. On the other hand, vertical roller mills offer superior energy efficiency and particle size control, making them ideal for cement and ore grinding applications. The choice between the two depends on specific requirements, budget constraints, and technical expertise.

How to install A Ball mill?

The first step of ball mill installation is to Install the base frame of the ball mill. The base installation uses a large number of metal partitions as base pads, prepare metal partitions with different thicknesses in advance for backup. After the base is installed, the worker can adjust the position of the base and the number of partitions according to the actual situation, the width of the partition cannot be less than 80mm, and the external exposed part should exceed at least 10mm In order to move the baffle, after the location of the baffle is determined, a welding operation is required. After the ball mill chassis is installed, it is necessary to accurately measure the levelness and level of the chassis with a spirit level and a tracking instrument.