According to relevant national standards, the hardness of barite ore grinding plant large gear should reach hb300 or above, and the tooth surface hardness of pinion should also be hrc45 or above.

However, some production units can not meet the above hardness requirements in actual production.This is needed to improve the hardness of barite ore grinding plant gears.

In addition, in order to save equipment maintenance time, some miners have omitted the internal stress treatment process of the gear, which makes it difficult for the gear to meet the hardness requirements in actual production, and then reduces the wear resistance of barite ore grinding plant gear.

The selection of lubricating oil and lubrication mode is not only an important means to ensure the normal operation of barite ore grinding plant gear, but also a necessary condition for noise reduction and wear reduction.

In the concentrator, the technicians chose barite ore grinding plant gear lubrication at random, and did not choose to use it respectively according to the different service characteristics and effects of different lubricating oils, nor did they choose the lubricating oil correctly according to the actual use situation on site.

This will lead to the insufficient viscosity of the lubricating oil during the operation of barite ore grinding plant gear, which can not effectively form a protective oil film, resulting in the wear of barite ore grinding plant gear.

In addition, there are still a few concentrators that use inferior lubricating oil as good, and use waste diesel oil as lubricating oil, which not only can not play the role of lubrication, but also accelerate the wear of barite ore grinding plant.

According to the specifications of barite grinding mill and customer needs, zenith can customize all aspects of barite grinding mill equipment to achieve the goals of energy saving, low consumption and high efficiency.

At present, the rotating speed of a large number of barite grinding mills is mostly 17R / min ~ 32R / min, and the running speed of small ring gear is mostly 120r / min ~ 200R / min.

The existing barite grinding mill generally adopts the transmission mode that the asynchronous motor drives the small gear ring after the speed is reduced by the reducer.

There are some defects, such as low efficiency, large land occupation, large amount of maintenance, large vibration and noise, large start-up impact and so on.

To solve this problem, zenith innovated the barite grinding mill drive system, replaced the original drive system with permanent magnet synchronous variable frequency speed regulation motor drive system, simplified the structure and further improved the transmission efficiency of the drive system.

Taking the 1000 t / D all sliming cyanidation carbon slurry plant project of Indonesia gold mine completed by Zenith 2018 as an example, we will elaborate the main contents of Raymond Mill commissioning of the project and the overall process of Raymond Mill commissioning from the three stages of Raymond Mill commissioning.

1、 Preparation stage before Raymond Mill commissioning preparation means that before starting Raymond mill, it is necessary to check whether all components meet the requirements of commissioning.

The main contents to be checked include lubrication, cooling, heating, sealing and fastening of various components.

Raymond Mill commissioning can be started only after the person in charge of each department ensures that all parts meet the conditions of commissioning.

Zenith wet overflow Raymond mill is selected for SBM Indonesia 1000t / D gold mine all sliming cyanidation project.

The grinding concentration determines the friction between grinding medium and material, pulp fluidity, effective density and effective weight of medium, and then affects the production efficiency of vertical roller mill. 

The grinding concentration also has a suitable range, which is too large or too small. In actual production, we generally advocate "high concentration grinding and low concentration classification". 

Generally, the grinding concentration is comprehensively determined by material properties, grinding process conditions, classification efficiency and overflow concentration. 

Taking the lattice vertical roller mill as an example, when coarse grinding (› 0.15mm), the grinding concentration should be controlled between 75 ~ 85%; When the overflow vertical roller mill is used to treat fine grinding products (0.10 ~ 0.074mm), the grinding concentration is generally controlled between 65 ~ 75%. 

 

In this case, Raymond mill is likely to cause "belly swelling", that is, the negative pressure in the cylinder is too large and the grinding effect is lost; However, if the ore feeding amount is insufficient, the ore discharge particle size of Raymond mill will become smaller and the sand return amount will be reduced accordingly.

In serious cases, the lining plate and grinding medium will make an obvious impact sound, resulting in the endless loss of grinding medium and lining plate.

When the ore feeding amount remains unchanged, the increase or decrease of ore feeding particle size will also be similar to the above situation. Therefore, the ore feeding quantity and particle size should be continuous, uniform and stable at a high level.

 

When entering the mill is too large, the grinding body and the lining plate will adhere, resulting in paste grinding, blocking the grate plate and full grinding. 

However, containing a small amount of moisture can effectively reduce the temperature and static electricity of vertical roller mill operation. Therefore, the average moisture of vertical roller mill operation is generally controlled at & lt; 15% is appropriate. 

Allowable moisture content of grinding material (for reference only) allowable moisture content of grinding material name rotary kiln and shaft kiln clinker 0.5 granular blast furnace slag 2.0 natural pozzolanic ash 2.0 limestone 1.5 clay 1.0 gypsum 10.06, vertical roller mill operation steel ball grading is unreasonable, which is to realize the impact and grinding of materials with different particle sizes, so as to improve the grinding efficiency, Therefore, the grading of vertical roller mill operation steel ball is very important.

 

Therefore, ensuring that the output of silica sand mill meets the standard is the top priority it is a very common problem that the output of silica sand mill fails to meet the design requirements in the production of concentrator. 

Under what circumstances will the output of silica sand mill fail to meet the design requirements? 1. 

The unreasonable design of the length proportion of each silo of silica sand mill will cause the imbalance of the coarse and fine grinding capacity of silica sand mill, resulting in the phenomenon of too coarse or too fine fineness of products, and then affect the output. 

Under normal circumstances, the length ratio of each warehouse of silica sand mill is as follows: warehouse number, warehouse type, 1 warehouse, 2 warehouse, 3 warehouse, single compartment 30 ~ 4060 ~ 70, double compartment 25 ~ 3025 ~ 3045 ~ 50.

 

Generally, the grading range is 25% ~ 35%, but the intermediate grading in practical application is mostly 28% ~ 32%. LM vertical roller mill steel ball grade ratio under common economic operation: steel ball diameter mm Φ one hundred Φ eighty Φ sixty Φ forty Φ 20 mass / total filling quantity 7.5% 6.9% 33.5% 30.1% 22 note: when the grindability of materials is poor or the grinding requirements are fine, the filling rate of one bin shall be & gt; 28%。

The temperature of LM vertical roller mill grinding material is too high. Generally, when the temperature of LM vertical roller mill grinding material is too high, it is easy to reduce the grinding efficiency. When the temperature of LM vertical roller mill exceeds 100 ℃, an air film isolated from each other on the surface of small particles of the material will be damaged, resulting in adhesion.

In order to reduce the temperature in the mill and improve the milling efficiency, a small amount of mist water can be sprayed into the milling bin to reduce the temperature in the mill to below 50 ℃.

Under what circumstances will the output of LM vertical roller mill fail to meet the design requirements? 

Unreasonable design of length proportion of each bin of LM vertical roller mill unreasonable length proportion of each bin of LM vertical roller mill will cause imbalance of coarse and fine grinding capacity of LM vertical roller mill, resulting in excessive coarse or fine fineness of products, and then affect the output. 

Generally, the length ratio of each warehouse of LM vertical roller mill is as follows: warehouse number, warehouse type, 1 warehouse, 2 warehouse, 3 warehouse, single compartment 30 ~ 4060 ~ 70, double compartment 25 ~ 3025 ~ 3045 ~ 50. Note: the data are for reference only, and the specific equipment warehouse length ratio shall be subject to the design of the manufacturer.