Negative-pressure turbo with blower uses the cooling principle of air convection and negative-pressure ventilation. It inhales fresh air naturally from the opposite side of the installation site, the door or window, and forces the indoor hot gas out of the room rapidly. Any poor ventilation problem can be improved. The cooling and ventilation effect can reach 90%-97%.
The strong advantages of negative pressure fan: 1. Low investment and low energy consumption. The same refrigeration rate, one-time investment is about one sixth of air conditioning, operating costs are about one tenth of air conditioning; 2. Strong cooling. Summer can cool more than 5-15 degrees, and the higher the temperature, the greater the range of cooling (indoor can be reduced to 25-30 degrees); 3, fresh and humid air. The air cleanliness can reach 99%.
Summary of negative pressure fan:
Negative pressure fan is the latest type of fan, which belongs to axial flow fan. It is called negative pressure fan because it is mainly used in negative pressure ventilation and cooling engineering. Negative pressure ventilation and cooling engineering includes two aspects: ventilation and cooling. The problems of ventilation and cooling are solved simultaneously. Negative pressure fan is also used in positive pressure water curtain environmental protection air conditioning, positive pressure air supply, positive pressure air blowing and other fields. The negative pressure fan has the characteristics of huge volume, super large duct, super large blade diameter, super large exhaust volume, super low energy consumption, low speed and low noise. The negative pressure fan is mainly divided into galvanized plate square negative pressure fan and glass fiber reinforced plastic trumpet negative pressure fan from the structural material. The structure and technical parameters of all galvanized sheet square negative pressure fans on the market are basically the same. The type classification of negative pressure fans will be described in detail. FRP horn negative pressure fan can be divided into belt type and straight knot type according to different transmission modes. The type classification of negative pressure fan will be explained in detail.
Ventilation principle of negative pressure fan:
The negative pressure fan discharges air outwards to reduce the indoor air pressure, and the indoor air becomes thinner. The characteristics of the negative pressure fan form a negative pressure area. The air flows into the room due to the compensation of the air pressure difference. In the practical application of industrial plant, the negative pressure fan is centrally installed on one side of the plant, and the air inlet is on the other side of the plant. The air is convective blown from the air inlet to the negative pressure fan. During this process, the doors and windows near the negative pressure fan remain closed, forcing air to flow into the workshop by compensating the doors and windows on the side of the intake port. The air flows into the workshop in an orderly line from the intake port, passes through the workshop, and is discharged from the workshop by a negative pressure fan. The ventilation is thorough and efficient, and the ventilation rate can be as high as 99%. Through specific engineering design, design ventilation speed and wind speed according to need, any high-heat, harmful gas, dust and smoke can be quickly discharged from the workshop, and any poor ventilation problem can be solved once and for all. The ventilator can be opened in a few seconds.
Type classification of negative pressure fan:
The structure and technical parameters of all square negative turbo with blower sold in the market are basically the same. The main models are 1380 * 1380 * 400 mm 1.1 kW, 1220 * 1220 * 400 mm 0.75 kW, 1060 * 1060 * 400 mm 0.55 kW and 900 * 900 * 400 mm 0.37 kW. The speed of all galvanized square negative pressure fans is 450 rpm, the motor is 4-pole 1400 rpm, the motor protection level is IP44, and the insulation level is B. Individual smaller size negative pressure fans lose their significance as negative pressure fans due to small air volume, high noise and low exhaust efficiency, so they are not described here. Comparing with large negative pressure fan, it is more efficient and energy-saving. FRP trumpet negative pressure fan can be divided into belt type and direct connection type according to its transmission structure. Belt-type speed is 370-450 rpm, using hexapole or quadrupole aluminium shell motor protection grade IP55, F insulation, low speed product noise is relatively low. The direct motor mainly has three types: 12 poles 440 rpm, 10 poles 560 rpm and 8 poles 720 rpm. The 12 poles motor is the most used, and the fan with high speed is noisy. Belt-type products are the most energy-saving, economical and durable. Straight-knot products are suitable for use in places where the belt-type can not work, such as oil pollution and corrosion of the belt. There are six, seven, three and five blades in the wind blade of FRP trumpet negative pressure fan. The materials of the wind blade are mainly die-cast aluminum alloy, engineering plastics (nylon plus fibre) and FRP. The number of blades, the angle and radian of the blades need to be matched reasonably with the speed and power. Single data can not explain the exhaust performance of the fan.
