Winnower

Yangchang machine

A hoist is a simple and messy equipment for grain, which can remove light and large impurities from grain and is beneficial for grain storage. Power: 3KW, conveyor belt is a seamless circular belt.

What is the working principle of a belt hoist?

Grain processing machinery is suitable for cleaning, screening, and grading. Various types of grain cleaning machinery use different working principles to separate grain particles and impurities. There are six commonly used types.

According to particle size separation, woven metal wire mesh and punched metal plate are used as screening surfaces. The cylindrical screen surface can be divided into reciprocating vibration or flat screen surface and axial screen surface. Compared with grain particles, there are two types of equipment for the sieve holes on the screen surface: ① The sieve holes are slightly larger than the diameter of the grain particles. Such as large sieve and cylindrical sieve. Its function is to allow grains and smaller impurities to pass through the sieve holes, while larger impurities are discharged as sieve residue. The large impurity sieve (Figure 1) feeds the grain into the circular working mesh belt, and during movement, it falls into the lower belt through the sieve holes along with small impurities. Large impurities such as paper, burlap bags, ropes, bricks, wood, and long straw are removed as sieve material, while some small impurities such as dust and sand particles are removed through the sieve holes as the grain continues to flow into the fixed inclined sieve surface at the outlet. Grains are subjected to strong suction treatment before being discharged from the machine. The main component of the cylindrical screen (Figure 2) is a horizontal cylinder composed of perforated screen plates. In addition to the suction and dust removal equipment, brushes for cleaning the sieve holes are also installed. Food enters the interior of the cylinder and is discharged through the large sieve holes. Large impurities accumulate on the sieve surface and are discharged from one end of the cylinder. Both are used for preliminary cleaning when grain is stored in the warehouse Grain particles with smaller sieve diameters than reciprocating vibrating screens, rotary screens, and high-speed vibrating screens. Small impurities in grain particles can be removed through sieve holes, and the grain can be discharged as sieve residue. All used for cleaning before processing after grain is released from the warehouse. The cleaned grain is discharged as the sieve material for the next layer of screening. If a larger sieve surface is replaced, it can also be used for preliminary cleaning. The reciprocating vibrating screen (Figure 3) is driven by an eccentric shaft or a self balancing vibrator and typically has three layers of screen surfaces. Screen out large impurities; Two layers of screening to remove large heterogeneous grains; Three layers of screening are used to remove small impurities. Both the inlet and outlet of grain are treated with suction to remove light impurities. The screen body of the flat rotary screen (Figure 4) is suspended on four sets of suspension rods, and the balance wheel drives the flat rotary motion, with two layers of screen surfaces. After changing the structure and working parameters, it can also be used for grading broken rice. The screen body of the high-speed vibrating screen undergoes small amplitude circular motion in a vertical plane under the centrifugal inertia force generated by the high-speed rotation of the balance weights on both sides, with 2-4 layers of screen surface. Used to separate barnyard grass from rice, the effect is better.

Separation by specific gravity is used to separate impurities such as stones, mud blocks, metal blocks, glass, ceramics, coal slag, etc. that are similar in size and shape to grain particles but different in weight. Separate dehumidification and drying methods: ① A typical separate dehumidification device is a wheat washing machine, which includes a spiral water washing tank and a vertical spin drying tank; Impurities with high specific gravity settle quickly in the washing tank, and the wheat particles that accumulate at the bottom of the tank and are transported from the small screw conveyor to the discharge outlet are floated to the drying part by the large screw conveyor, removing the free water on the surface Dry process equipment includes a specific gravity sorting device and a specific gravity sorting device. Grain is uniformly fed into a porous plate (fish scale porous plate or steel wire woven mesh plate) that undergoes inclined reciprocating vibration in the specific gravity stone removal machine (Figure 5), and is fluidized by controlling the airflow. The semi suspended state flows towards the lower end through its own weight and is discharged. Heavy stones, mud blocks, and other materials vibrate back and forth, causing the porous plate to move upwards and be discharged from the aggregate area. There are two ways to provide airflow: inhalation and blowing. The working principle and structure of the specific gravity grading table are similar to those of the specific gravity stone removal machine: first, the grain and impurities are divided into two parts by weight, and then cleaned separately, which can reduce the number of cleaning equipment or smaller equipment. Dry equipment can save water, prevent wastewater from polluting the environment, facilitate maintenance, and gradually replace wet equipment. Impurities and materials separated by shape are similar in size to grain particles, while buckwheat, peas, awnless crickets, oats, barley, and others have different shapes. Typical equipment includes: ① Spiral separator. It does not require moving parts or electrical equipment, and its vertical axis has a large outer helical surface surrounding some small inner helical surfaces. Grains enter the entrance of the internal rotation surface, and impurities from spherical seeds roll quickly and have a large momentum, which can be thrown into the external rotation surface under centrifugal force and discharged from the outlet. Grain particles flow along each inner helical surface towards each outlet. The device has low productivity and can only be used as an auxiliary device Drum selection machine (Figure 6). Its working part is a slightly inclined horizontal rotating drum with many groove holes (bag holes) on the inner wall, and a spiral collection groove with adjustable position in the center. Any particles (spherical and small) that can remain in the nest will be lifted by the rotation of the drum and fall into the spiral collection groove, and then the grains will be discharged through the discharge end of the drum Nest eye disc selection machine. Its working components are one or several sets of disks installed coaxially (Figure 7), with dense holes on the surface. When the dish rotates and food is buried in the lower part, it will enter the nest and bring short grains (buckwheat, awnless elm, broken rice, etc.) to a certain height, and fall into the collection trough next to the machine and flow out.

According to the natural properties of impurities, such as separating magnetic impurities, permanent magnets can be installed on the feed chute of grain processing machinery to adsorb impurities onto the surface of the magnetic steel and clean them regularly manually. Persistent magnet drum and electromagnetic drum can also be used. Fixed semi cylindrical persistent magnet steel and electromagnetic steel are installed inside the non-magnetic drum. Grain flows along the surface of the drum towards the outlet, and magnetic impurities are adsorbed on the surface of the drum by the magnet steel. As the drum rotates to an area without magnet steel, they detach from the collection container. Separate colored particles from grains (such as rye in wheat, red rice in rice, yellow brown rice, etc.). The photoelectric sensing device is installed in each narrow slot parallel to the machine, and the grain flows through the narrow slot in a thin and narrow stream. When colored particles flow into the light region, their reflection characteristics cause the sensor to emit information, open the valve at the bottom of the narrow groove, and discharge the colored particles. This device has good performance, but low productivity. The crickets in rice and brown rice can be separated using an electrostatic cricket removal machine, where the grains are evenly and thinly fed into the machine. The crickets exhibit significant polarization in a strong electrostatic field and tend to be discharged from the machine towards the mechanical side.