Single Action Single Stage Liquid Ring Vacuum Pump 0.12 To 27m³/Min 2.2 KW To 130 KW

The SZ series liquid ring vacuum pump 0.12 to 27 cubic meters per minute

I. Introduction

The SZ series liquid ring vacuum pump is a classic and widely used line in China's industrial sector, with a history dating back to the last century. This series features single-stage, single-action pumps that function as both vacuum pumps and compressors. Its working principle involves an impeller eccentrically mounted within an oval-shaped pump chamber. As the impeller rotates, the sealing liquid (typically water) forms a liquid ring due to centrifugal force. The oval shape of the chamber causes the volume of the sealed spaces between the impeller vanes and the liquid ring to change periodically, thereby achieving gas intake, compression, and discharge.

Known for its simple structure, ruggedness, and economical price, the SZ series remains a reliable choice in many traditional industries, although its efficiency and ultimate vacuum are generally lower than newer series like the SK.

II. Advantages

1. Simple and Robust Construction: Features a classic design with relatively few components. Its mechanical structure is sturdy and reliable, capable of withstanding harsh conditions and long-term continuous operation.

2. Low Maintenance Cost: The simple structure makes it easy to disassemble, inspect, and maintain. It requires lower technical skill for maintenance, and spare parts are readily available and inexpensive.

3. Isothermal Compression & High Safety: The minimal temperature rise during compression makes it highly suitable for handling flammable and explosive gases safely.

4. Handles Wet Gases: Can pump or compress gas-liquid mixtures containing droplets without risk of liquid hammer and is tolerant of minor dust content.

5. Dual-Purpose Machine: Can be used as both a vacuum pump and a low-pressure compressor.

6. Cost-Effective: Offers low initial purchase cost and long-term maintenance cost, providing high value for money.

III. Key Technical Parameters

• Model Example: SZ-1, SZ-2, SZ-3, SZ-4 (The number historically indicated a performance level, not strictly linear with parameters).

• Pumping Speed (as Vacuum Pump): Typically ranges from 0.12 to 27 cubic meters per minute (2 to 450 liters per second). For example:

  • SZ-1: ~1.5 m³/min

  • SZ-2: ~3.4 m³/min

  • SZ-3: ~11.5 m³/min

  • SZ-4: ~27 m³/min

• Ultimate Vacuum (as Vacuum Pump): Can reach -0.087 MPa to -0.093 MPa (87% ~ 93% vacuum degree, or 13kPa ~ 7kPa abs. pressure).

• Discharge Pressure (as Compressor): Typically up to 0.1 ~ 0.15 MPa (G).

• Motor Power: Covers a wide range, from 2.2 kW to 130 kW, depending on the specific model.

• Operating Liquid Flow: Requires a continuous supply of sealing liquid, with a flow rate of approximately 10-100 liters per minute.

• Material of Construction: Main components are generally cast iron.

IV. Application Fields
The SZ series pump is widely used in traditional industries due to its economy and reliability:

• Vacuum Applications (as Pump):

  • Chemical & Pharmaceutical Industries: Vacuum filtration, vacuum drying, vacuum evaporation, vacuum crystallization.

  • Food Processing: Vacuum packaging, vacuum concentration.

  • Ceramics & Building Materials: Clay vacuum treatment, brick dewatering.

  • Machinery Industry: Vacuum lifting systems, central vacuum supply.

  • Light Industry: Deaeration in plastic extruders.

• Pressure Applications (as Compressor):

  • Gas Transfer: Transferring gases like chlorine, hydrogen, carbon dioxide (material selection depends on the medium).

  • Sugar Industry: Agitating and transferring syrup.

  • Wastewater Treatment: Aeration.

  • Pneumatic Systems: Providing air supply for low-pressure pneumatic devices.