JZJ2B Series Roots-Water Ring Unit -- Water Ring Vacuum Pump -- Vacuum Unit

Overview:
The JZJ2B series Roots water ring unit is a gas extraction unit composed of a ZJ-type Roots pump as the main extraction pump and a 2BV series water ring pump or Roots-water ring unit as the fore pump. In addition to extracting general gases, it can also extract gases containing moisture, organic solvents, or a small amount of dust. Compared to general mechanical vacuum pumps, it is not afraid of oil contamination, water vapor, or fine dust. Compared to general water ring vacuum pumps, it features higher vacuum levels and greater pumping speeds under high vacuum conditions.
By utilizing the energy-efficient 2BV series water ring pump as the fore pump, the JZJ2B series vacuum unit offers higher efficiency, a more compact structure, no leakage (the 2BV pump uses mechanical sealing, unlike the gland packing seal of the 2SK series), corrosion resistance (2BV uses stainless steel or aluminum bronze impellers), and a high protection level compared to the JZJ2S series.
The Roots vacuum pump employs the independently developed ZJ series Roots vacuum pump from our company. The improved ZJ series Roots vacuum pump, with enhanced sealing between the pump chamber and bearing chamber, prevents pump oil from easily emulsifying during processes involving the extraction of large amounts of water vapor and various solvents.
The working fluid for the fore pump of the Roots water ring vacuum unit is mostly water, but organic solvents (such as methanol, ethanol, xylene, acetone, etc.) or other liquids can also be used. Using the fore pump as a closed-loop circulation system significantly reduces environmental pollution and greatly improves the recovery of organic solvents. The ultimate vacuum level is determined by the saturated vapor pressure of the working fluid.

Key considerations for selecting a Roots unit:
1. Understand the composition of the gas being extracted, including whether it contains condensable vapor, particulate dust, or corrosive elements. When selecting a vacuum pump, it is necessary to know the gas composition and choose the appropriate pump accordingly. If the gas contains vapor, particles, or corrosive gases, auxiliary equipment such as condensers or dust collectors should be installed on the pump's intake pipeline.
2. The operating pressure of the Roots vacuum unit should meet the ultimate vacuum and working pressure requirements of the vacuum equipment. For example, if a vacuum drying process requires a working pressure of 10 mmHg (absolute), the selected vacuum pump should have an ultimate pressure of at least 2 mmHg, preferably below 1 mmHg. Typically, the pump's ultimate pressure should be half to one order of magnitude higher than the working pressure of the vacuum equipment.
3. Correctly select the operating point of the Roots vacuum unit. The normal operating range of the Roots vacuum unit is from the maximum inlet pressure to 5 times the ultimate pressure. For example, the normal operating range of the JZJ2B150-2.1 Roots water ring vacuum unit is 6000 Pa to 125 Pa. This range represents the optimal operating pressure range after the main pump is started, where the unit operates most efficiently.
4. Under its operating pressure, the vacuum unit should be able to evacuate all gases generated during the vacuum equipment process.
5. Select the appropriate unit configuration based on actual working conditions. For example, the JZJ2B300-4.1 and JZJ2B300-2.1 units have the same maximum pumping speed and ultimate pressure, but differ in their operating ranges and power consumption. The normal operating range of the JZJ2B300-4.1 unit is 2000 Pa to 125 Pa, while the JZJ2B300-2.1 unit operates from 5000 Pa to 125 Pa. Clearly, the JZJ2B300-2.1 unit has a wider operating range but consumes more power. If the system's working pressure is confirmed to be below 2000 Pa, the JZJ2B300-4.1 unit should be prioritized to save energy. However, if the unit requires strong pre-pumping capability and needs to operate at higher pressures for extended periods, the JZJ2B300-2.1 unit with a larger fore pump is more suitable.

Model designation method:
Example: J Z J 2 B 1 5 0 － 2 . 1
J represents the first letter of "unit"
ZJ indicates the main pump is a ZJ series Roots vacuum pump
2B indicates the fore pump is a 2BV/2BE series water (liquid) ring vacuum pump
(2S indicates the fore pump is a 2SK series water (liquid) ring vacuum pump)
150 is the pumping speed of the main pump (Roots pump) in L/s
2.1 is the pumping speed ratio code
(i.e., the pumping speed ratio between the main pump and secondary pump is 2, and between the secondary pump and fore pump is 1)

JZJ2B series Roots-water ring vacuum unit technical specifications:

Notes: 1. The above table only recommends standard series. Due to varying working conditions in practical applications, inlet gas and pressure may change significantly. Therefore, selection should be based on actual pumping processes, gas release processes, condensation of condensable gases, time-varying inlet pressure, etc., through verification calculations or by referencing existing equipment usage. Roots vacuum pumps and water ring vacuum pumps can also be configured separately based on actual conditions.
　　　 2. For detailed technical specifications of individual pumps, refer to the respective pump's technical parameters.
　　　 3. If explosion-proof requirements are needed for vacuum pump motors, electrical contact vacuum gauges, control cabinets, etc., please specify during ordering. The corresponding 2BV5 series in the table should be replaced with the 2BV6 series.
　　　 4. The maximum inlet pressure refers to the highest pressure at which the main pump can start. Starting the main pump above this pressure may cause overload.