There are several types of fan fans for mine ventilation? What is its structure and working principle?

Commonly used fan fans, in terms of its construction, there are two types of centrifugal and axial flow.

The centrifugal fan is shown in Figure 1. When the working wheel rotates inside the spiral casing, due to the centrifugal force generated by the blade, a low pressure region appears in the central portion of the working wheel to draw in air; the rim portion generates a high pressure region to press air out of the diffuser. When the working wheel is continuously rotated by the motor, the air continuously enters from the suction port and is forced out from the diffuser through the working wheel.

Figure 1 Schematic diagram of a centrifugal fan

The axial flow fan is shown in Figure 2. When the working wheel rotates continuously, since the blade is in the shape of a wing and has a certain angle with the rotating surface (as shown in FIG. 3), a low pressure region is taken in the rear of the blade to take in air, and a high pressure region is generated in front of the blade to press air. This continues to create a romantic flow. In order to improve the efficiency of the fan, the streamline body is installed on the air inlet side of the working wheel to reduce the impact loss; the rectifier is installed on the air outlet side, which is a fixed working wheel for the purpose of overcoming the rotating wind flow discharged by the working wheel; The diffuser is then used to increase the static pressure. In order to increase the wind pressure of the fan, a set of working wheels and rectifiers can be added, which is called a secondary axial fan. The angle between the blade of the axial fan and the rotating surface is called the mounting angle. The mounting angle θ can be adjusted. As the installation angle increases, both wind pressure and air volume increase. The general installation angles are seven angles of 15°, 20°, 25°, 30°, 35°, 40°, and 45°.

Figure 2 Schematic diagram of axial fan

1-working wheel; 2-blade; 3-shell; 4-collector;

5-rectifier; 6-streamline body; 7-diffuser

Figure 3 Blade mounting angle of an axial fan

Θ-blade mounting angle; t-blade spacing

Fan fans used in mines can be divided into: fan fans for ventilation in the whole mine, called main fan fans, referred to as main fans; fan fans used to enhance ventilation in a certain area, called auxiliary fan fans, referred to as auxiliary fans; The fan fan used for the single-head working surface is called a local fan, which is referred to as a local fan. These fans have different characteristics depending on the requirements of use.

Tension Roller

Continuous annealing furnace with furnace roll

Make various types of roller from small diameter (60mm) to large diameter (1600mm). In particular, the large diameter Furnace Roller used in continuous annealing production line with higher reliability is highly appraising. In addition, it also produces special roller for measuring temperature and equalizing temperature.

High speed wire rod mill at home, at the wire rolling mill, rod line and use of roller slit rolling mill ring, due to the work under the roll ring in relatively poor thermal conditions, therefore must be able to withstand the wear and corrosion of cooling water and the big rolling torque and so on, at present a lot of manufacturers adopt tungsten carbide tungsten carbide roll rings, but because the cost of tungsten carbide roll ring manufacturing high, caused the enterprise production costs rise, and in view of the actual situation, our factory successfully developed special wear-resistant alloy MSW66552 series, nearly half of the manufacturing cost is tungsten carbide, the effect of using basic tungsten carbide. The e product has been confirmed by the user, MSW66552 alloy product hardness 88HS, roll surface hardness difference less than 2HS, 6000C red hardness more than 82HS, roll body radial 30mm hardness difference less than 3HS, impact toughness more than 15J/CM2, fracture toughness more than 60Mpa. M1 /2.