Stainless Steel Roots Blower

Stainless Steel Roots Blower

• Advantages of stainless steel roots blower
• Based on the introduction of Japanese SR series and R series fans, the company developed a compressor based on years of successful design and processing experience based on the successful experience and problems in the MVR project. Its characteristics are specifically reflected in the following aspects:

Stainless Steel Roots Blower

Corrosion problem

• For the common corrosion problems of steam fans, anti-corrosion of the flow-passing parts of the fans
• SUS304, SUS316L, and 2205 dual-phase steel are available. SUS304 is used in working conditions with a small temperature rise; 2205 stainless steel is used in high temperature and harsh working conditions due to its small thermal expansion coefficient and good corrosion resistance. 2205 fans are the perfect choice for long-term safe and efficient operation.
• Cast iron with Ni-P coating or Teflon coating can be used. The advantage is that the thermal expansion coefficient of cast iron is much lower than that of stainless steel, which can effectively prevent the rotor from seizing during rotation.
• Roots blower is a volumetric rotary blower. Each concave curved surface part on the rotor and the inner wall of the cylinder form a working volume. During the rotation of the rotor, the gas is taken away from the suction port. When it moves to the vicinity of the exhaust port, it is connected to the exhaust port. At the moment of passage, due to the rotation of higher pressure air flow, the pressure in the working volume suddenly rises, causing the steam temperature to rise.
• The two rotors work alternately in sequence. The two rotors do not contact each other, and the gap between them is tightly controlled to achieve sealing, so the discharged gas is not contaminated by lubricating oil.
• The high-speed centrifugal compressor is based on the principle of converting kinetic energy into potential energy. It uses a high-speed rotating impeller to accelerate the gas, then decelerates it, changes the flow direction, and converts the kinetic energy into potential energy. The main feature of high-speed centrifugal compressors is the compact arrangement of the binary impeller and compressor and gearbox. The motor, gearbox and compressor are usually mounted on the same base. It has the characteristics of low noise and high efficiency. Since the linear speed of the outer end of the impeller is greater than 400m/s and it is highly stressed, it is generally made of chromium-nickel steel or titanium alloy.
• The centrifugal blower has the characteristics of low compression ratio and large flow rate. Like the centrifugal compressor, the gas enters the impeller inlet from the axial direction and flows out radially under the action of centrifugal force. The fan impeller and casing are of welded plate structure and require the use of reinforcing ribs. A gearbox is usually not required and the drive system can achieve the required impeller speed. Due to the low compression ratio, the temperature rise is usually 6-8°C, and two units are often used in series in MVR systems.

Sealed form

• Use multiple labyrinth seals, double shaft seals (the oil seal made of VITON prevents lubricating oil from the tank from entering the side/main box, and the seal made of fluorine rubber prevents steam from entering the tank), and can be flexibly matched according to needs such as air backflush seals and mechanical seals.
• The combination can ensure that the seal of the compressor can be effective and reliable for a long time under positive or negative pressure working conditions and in different media environments such as water vapor or alcohol vapor; under conditions with particularly high application environmental requirements, we will combine the working chamber and The structure of the labyrinth + PEPE piston ring seal between the side bodies has been changed to a dedicated steam seal, which no longer distinguishes between positive and negative pressure application environments. Please refer to the special sealing process documents for details.

Cavitation of stainless steel fans

• Causes of cavitation: In valves, throats and other parts of the fluid, when the streamline interval narrows sharply and the flow rate increases, and when the pressure drops below the saturated vapor pressure of the fluid, the fluid boils and the fluid in the fluid Excess air separates, creating bubbles. When these bubbles generated in low-lying parts move like high-pressure parts, they are squeezed by the surrounding pressure, and the phenomenon in which their volume decreases and even ruptures is called cavitation. When cavitation occurs, a strong shock wave will be generated when the bubbles burst under the pressure of the surrounding pressure. When the pressure is relatively high, the impact energy will damage the metal surface.
• Prevention of cavitation
  As a measure to prevent cavitation
  (1) Control the circumferential speed of the rotor to be 30m/s or less below the current circumferential speed where cavitation does not occur.
  (2) Use 2205 dual-phase steel with good cavitation resistance.
  (3) Add appropriate amount of spray water to the inlet of the Roots blower to control the outlet temperature.