What are the 400 mesh ore grinding machines available for processing?

"400 mesh" refers to a particle size range of 20 micrometers to 75 micrometers, which is typically used in the mining and mineral processing industries for grinding various ores. There are various types of grinding machines available that can be used to achieve the desired mesh size, including:

1. Ball Mills: They use steel or ceramic balls to grind the ore into a powder. The grinding process happens as the balls collide with each other and the ore particles. These mills can be batch or continuous process mills and are available in various sizes and configurations.

2. Rod Mills: These mills use rods instead of balls for the grinding process. They are generally used for coarser grinding than ball mills and can achieve a mesh size of 65 to 200.

3. Autogenous Mills (AG Mills): These mills use the ore itself as the grinding media, with the particles scraping and grinding against each other. They are typically used for larger scale operations.

4. Semi-Autogenous Mills (SAG Mills): These are a hybrid type of mill that combines the action of a ball mill and an AG mill. They use a combination of ore particles and metal balls for grinding.

5. Horizontal Roller Mills: These mills use horizontal rollers with a grinding track to process the ore. They can achieve high throughputs with relatively low energy consumption.

6. Vertical Roller Mills: These mills are designed with a vertical axis and use rollers to grind the ore. They are energy-efficient and suitable for various applications.

7. Jet Mills: These mills use a high-pressure stream of air or other gases to impact and grind the ore particles. They are suitable for ultra-fine grinding and can achieve mesh sizes down to 10 micrometers.

8. Impact Mills: These mills use a rotating disc with hammers or pins that impact the ore particles, breaking them down into smaller sizes. They can achieve coarse to medium grinding depending on the configuration.

9. Stirred Mills: Also known as Attrition Mills, these mills use a rotating horizontal axis with stirrers to mix and grind the ore. They are suitable for fine and ultra-fine grinding.

10. Classifiers: While not a grinding machine per se, classifiers are often used in conjunction with grinding mills to separate the final product based on particle size.

When selecting a grinding mill, several factors need to be considered, including the required mesh size, throughput, energy efficiency, and the ore's composition and properties. It is common for mines to use a combination of milling machines to achieve the desired particle size distribution for processing.