The difference between negative pressure Roots blower and positive pressure Roots blower
The main differences between negative pressure Roots blowers and positive pressure Roots blowers are reflected in the following aspects:
1、 Working principle and structure
1. Negative pressure Roots blower:
The main way to achieve vacuum pumping is through inhalation, so the design of its air inlet is crucial.
The air intake is usually equipped with a muffler and directly connected to the main pipe, while the exhaust muffler mainly serves the exhaust effect.
The negative pressure fan generates negative pressure suction from one side of the factory building, and the air enters from the wind and passes evenly through the interior of the factory building, causing the air inside the factory building to mix evenly.
2. Positive pressure Roots blower:
Mainly using exhaust ports to generate positive pressure by expelling air to the outside.
Its structure may be simpler compared to negative pressure fans, as there is no need to specifically consider the complex design of the air inlet.
The positive pressure fan sucks in air from the rear and discharges it towards the front, and the wind force is related to the distance between the fans.
2、 Range of work pressure
1. Negative pressure Roots blower:
The range of work pressure is usually between -9.8 kPa and -46.6 kPa.
2. Positive pressure Roots blower:
The working pressure range is usually between 10kpa and 98kpa.
3、 Application scenarios
1. Negative pressure Roots blower:
Commonly used in situations where vacuum or negative pressure suction is required, such as vacuum packaging, negative pressure suction systems, etc.
In industrial plant applications, negative pressure fans are centrally installed on one side of the plant, with the air inlet on the other side of the plant. Air flows through the air inlet to the negative pressure fan to form convective blowing.
2. Positive pressure Roots blower:
Commonly used in situations where air supply or positive pressure is required, such as pneumatic conveying, aeration, sewage treatment, etc.
Positive pressure fans are also commonly used in situations where indoor air pressure needs to be increased or fresh air needs to be provided, such as ventilation systems.
4、 Performance characteristics
1. Negative pressure Roots blower:
Capable of generating strong negative pressure suction, suitable for situations that require rapid removal of indoor gases or dust.
The noise during operation is relatively low and can maintain a relatively stable negative pressure state.
2. Positive pressure Roots blower:
Capable of providing stable positive pressure output, suitable for situations where gas needs to be delivered to the outside or positive pressure needs to be provided.
The noise and vibration that may be generated during operation can usually be reduced by installing mufflers and shock absorbers.
In summary, there are significant differences between negative pressure Roots blowers and positive pressure Roots blowers in terms of working principle, working pressure range, application scenarios, and performance characteristics. The choice of type of Roots blower depends on specific application requirements and working environment.
