Roots blower of introduction

What is roots blower：

Roots blower, also known as Roots blower, is a volumetric rotary blower, using two or three blade rotors in the cylinder for relative motion to compress and transport gas rotary compressor. The blower is simple in structure and convenient in manufacture. It is suitable for gas conveying and pressurizing in low pressure situations and can also be used as a vacuum pump. Its biggest characteristic is that when the pressure is adjusted within the allowable range, the flow rate changes slightly, the pressure selection range is very wide, and it has the characteristics of forced gas transmission. When conveying, the medium is not oily. It has simple structure, convenient maintenance, long service life and small vibration of the whole machine.

Due to periodic suction, exhaust and instantaneous constant volume compression, the gas velocity and pressure fluctuation will be caused, which will produce a larger aerodynamic noise. In addition, the clearance between the rotor and between the rotor and the cylinder will cause gas leakage, thus reducing efficiency. The exhaust volume of Roots blower is 0.15 to 150 cubic meters / minute, and the rotation speed is 150~3000 rpm. The single stage pressure ratio is usually less than 1.7, up to 2.1, and can be used in series.

Roots blower transport medium for clean air, clean gas, sulfur dioxide and other inert gases, special gas industries (gas, natural gas, methane, carbon dioxide, sulfur dioxide, etc.) and high-pressure working conditions of the preferred products. In view of the above characteristics, it can be widely used in metallurgy, chemical industry, fertilizer, petrochemical, instrumentation, building materials industry.

According to the shape of the rotor, roots blower is divided into two leaf type and three leaf type. The three leaf rotor is rotated and rotated by two rotors for three times at each rotation. Compared with the two blade type, the gas pulsation is small, the vibration is small, and the noise is low.
The speed of Roots blower is 150~3000 revolutions / min. The flow rate is 0.15-1200 cubic meters per minute, the pressure is 9.8-196 kPa, the power is 0.75-1000 kW, the single machine weight is 100-9000 kg.

The difference between Roots blower and centrifugal fan is quite different:

1.The working principle of the centrifugal fan is different. The centrifugal fan uses curved blades, and the centrifugal force is used to throw the gas to the casing. The Roots fan uses two 8-shaped blades, and the gap between them is very small. By the extrusion of the two blades, the gas is squeezed to the outlet.

2.Owing to the different working principles, the working pressure of roots fans is generally different, and the outlet pressure of roots fans is higher, while that of centrifugal fans is smaller.

3.Different air volume, general Roots blower used in the air volume requirements are not large but high pressure, and centrifugal blower used in low pressure requirements, air volume requirements in places.

4.Manufacturing accuracy is different, Roots fan requires high precision, assembly requirements are also strict, and centrifugal fan is relatively loose.