At present, the commonly used vacuum feeding machines in our country are divided into electric feeding machines and pneumatic feeding machines, which can replace manual automatic feeding into equipment such as hoppers, reaction tanks, dryers, mixers, etc. They also have the function of automatic dust collection and dust removal. The conveying capacity of the conveyor is generally between 100-5000kg/h.
The main features of the vacuum feeding machine are:
1. The vacuum feeding machine consists of a vortex vacuum pump (without oil or water), a membrane filter bag filter, a compressed air backflushing device, a pneumatic discharge door device, a vacuum hopper, a stainless steel adjustable suction gun, a conveying hose, and other components.
2. The motor is powered by a vortex vacuum pump, which is oil-free, water-free, and maintenance free.
3. The entire conveying process is completed in a completely enclosed state, eliminating dust pollution.
4. The body is a modular structure, and the barrel body is connected with quick opening clamps, making disassembly and cleaning convenient and fast.
5. Low energy consumption, low noise, and convenient control.
6. Special S-shaped flanging is used between barrels to effectively prevent dust leakage

The screening efficiency and productivity of the rotary vibrating screen are the technical and economic indicators of the screening process. There is a certain relationship between them, and it is also related to other factors. The following three categories are the main factors that affect the screening process:
1、 The Properties of Sieve Surface and the Influence of Its Structural Parameters
The vibrating screen causes particles to move vertically with the screen surface, resulting in high screening efficiency and large production capacity. The relative motion between particles and the screen surface is mainly parallel to the bar screen, plane vibrating screen, and tube screen, which have low screening efficiency and production capacity. For a certain material, the productivity of the sieve is determined by the size of the sieve opening. The productivity depends on the width of the screen surface, which has a high productivity. The larger the effective screening area (i.e. the ratio of the sieve aperture area to the entire sieve surface area), the higher the unit area productivity and screening efficiency of the sieve surface. The larger the mesh size, the greater the productivity per unit sieve surface and the higher the screening efficiency.
2、 Physical properties of screened materials
The particle size composition, humidity, mud content, and particle shape of the material itself. When the content of fine particles in the material is high, the productivity of the sieve is also high. When the material humidity is high, the screening efficiency generally decreases. However, the larger the sieve size, the smaller the impact of moisture. Therefore, for wet materials with high moisture content, in order to improve the screening process, it is generally possible to increase the sieve size or use wet screening. Wet screening or pre washing should be used for materials with high mud content.
3、 The impact of production conditions
When the load of the sieve is large, the screening efficiency is low. The flatness of the sieve largely depends on the size of the sieve aperture and the overall screening efficiency; The larger the sieve aperture, the lower the screening efficiency required, and the higher the productivity. The uniformity of feed is of great significance for the screening process. The amplitude and frequency of the rotary vibrating screen are related to the structural and physical properties of the screen. Within a certain period of time, increasing vibration can improve the screening index.

1) The structure is relatively simple and the cost is relatively low [4].
2) Reliable work, easy maintenance and management.
3) Compact size, small cross-sectional size, and small footprint. It is easy to enter and exit hatches and carriages during unloading operations at ports.
4) It can achieve sealed transportation, which is conducive to transporting materials that are prone to flying, hot, and strongly odorous, reducing environmental pollution, and improving the working conditions of port workers.
5) Convenient loading and unloading. The horizontal screw conveyor can load and unload at any point on its conveying line; The configuration of a relatively spiral reclaiming device for vertical screw conveyors can have excellent reclaiming performance.
6) It can be transported in reverse direction, and can also enable a conveyor to simultaneously transport materials in two directions, namely towards the center or away from the center.
7) The unit energy consumption is relatively high.
8) Materials are prone to grinding and wear during transportation, and the wear of spiral blades and material grooves is also severe.

The installation requirements for screw conveyors are:
1. 20 days before the installation of the screw machine, the foundation should be well watered. This foundation should ensure sufficient stability of the screw machine during operation.
2. Before installing the screw machine, all parts should be thoroughly counted and various pollutants inside and outside should be cleaned.

3. The adjacent flange surfaces should be connected smoothly and tightly, and the misalignment deviation at the joints on the inner surface of the casing should not exceed 1.4mm.

4. Asbestos rubber plates are allowed to be placed between the casing flanges to adjust the accumulated error in the length of the casing and spiral body.

5. The nominal distance between the outer diameter of the screw and the casing is consistent

6. The suspension bearings of the screw conveyor should be reliably fixed on the lifting ears of the casing, and after connecting with adjacent screws, the screw rotation should be uniform. During installation, adjusting shims can be added between the suspension bearing support and the casing lifting ears to ensure that the coaxiality of the spiral axis meets the requirements

7. When the screw machine is single drive, the tail bearing blind cover should be opened, and the distance from the bearing end face to the blind cover should be measured to be less than 20mm.

8. The coaxiality between the main shaft of the screw machine and the reducer shaft should comply with the provisions of GB1184-80 "Regulations on Shape and Position Tolerances without Individual Tolerance Indications".
9. After the chassis of the screw machine is installed, tighten the foundation bolts.
10. Tighten all connecting bolts to a reliable level.
11. The cover of the screw conveyor should be installed in sequence, with a cover buckle installed at an interval of about 0.5m. The last cover at each overlap of the cover should have a cover buckle installed, and one to two cover buckles should be installed at both ends of the screw conveyor to ensure the sealing of the screw conveyor.
12. The dust collection port, feed port, and discharge port should avoid the overlap between the casing flange and the machine cover, and generally adopt on-site welding

Application of rotary vibrating screen in chemical industry
Application of Large-scale Rotary Vibrating Sieve in Chemical Industry

Rotary vibrating screen is a commonly used screening equipment, which is widely used in material screening, classification, removal of impurities and other processes in the chemical industry. Here are a few applications of rotary vibrating screens in the chemical industry:

Classification and screening: rotary vibrating screen can be used for classification and screening of chemical raw materials, intermediates and products. For example, for the screening of polymer particles, screens with different apertures can be used according to the particle size to separate particles of different particle sizes to meet the needs of different particle sizes. In addition, for the classification and screening of granular materials such as catalysts, adsorbents, and activated carbon, rotary vibrating screens are also commonly used equipment.

Removal of impurities: There are often impurities in raw materials, intermediates and products in the chemical industry, such as metal particles, fibers, particles, etc. These impurities will affect the quality of materials and process efficiency. The rotary vibrating screen can be used to remove these impurities to ensure the quality of the material. For example, for metal particles in granular materials, a combination of magnetic screening and rotary vibrating screen can be used to remove metal particles to achieve the purpose of purifying materials.

Recycling: In the chemical industry, some materials can be recycled through rotary vibrating screens. For example, for materials such as waste polymers and waste liquids, they can be classified, screened, and dried through rotary vibrating sieves to recycle useful materials and reduce waste rates and waste of resources.

In short, the rotary vibrating screen has a wide range of applications in the chemical industry, and is often used in material screening, classification, removal of impurities, recycling and other processes. When using a rotary vibrating screen, it is necessary to select appropriate parameters such as screen aperture, amplitude and vibration frequency according to the material properties and screening requirements to ensure the best screening effect and productivity.

Rotary vibrating screen is a commonly used screening equipment, which is widely used in materials screening, grading, removing impurities and other processes in the construction industry. Here are a few applications of rotary vibrating screens in the construction industry:

Sand screening: The sand and gravel materials commonly used in the construction industry need to be screened to meet the needs of different particle sizes. The rotary vibrating screen can be used to screen and classify sand and gravel materials to separate sand and gravel particles that meet the requirements. At the same time, the rotary vibrating screen can also remove impurities in the gravel and improve the quality of the gravel.

Cement production: The rotary vibrating screen can be used for material screening in cement production. For example, in the production process of cement raw materials, limestone, clay and other materials need to be screened to separate the material particles that meet the requirements and ensure the quality of cement.

Concrete Production: In the process of concrete production, the aggregate needs to be screened to meet the strength and quality requirements of the concrete. The rotary vibrating screen can be used for sieving and grading the aggregate to separate the aggregate particles that meet the requirements and remove impurities and dust.

Construction waste treatment: Construction waste often contains useful bricks, steel bars and other materials, which can be separated and recycled by rotary vibrating screens. The rotary vibrating screen can be used to screen, classify, remove impurities and other processes for construction waste, reduce waste disposal costs and improve resource utilization.

In short, the rotary vibrating screen has a wide range of applications in the construction industry, and is often used in sand and gravel screening, cement production, concrete production, construction waste treatment and other processes. When using a rotary vibrating screen, it is necessary to select appropriate parameters such as screen aperture, amplitude and vibration frequency according to the material properties and screening requirements to ensure the best screening effect and productivity.