JZJ2B series Package Units
One Roots pump+water ring vacuum pump unit
One Roots pump+water
ring vacuum pump unit
Two Roots pumps+water
ring vacuum pump unit
Three Roots pumps+water ring vacuum pump unit
Summary
JZJ2B package
unit is composed of one set of ZJ Roots
pump as the main suction pump and one set of 2BV
water ring vacuum pump or a package unit as the fore pump. Except
for pumping the normal gases, they can also pump other gases that contain
moisture, organic solvent or dust. Comparing with the common mechanical
vacuum pump, the Roots unit is not easy to be the polluted by the oil,
moisture and dust. And comparing with the water ring vacuum pump, it has
higher vacuum and bigger suction capacity when it operates in the high
vacuum.
The package units are used extensively in many areas such as chemical,
electric, machinery, pharmacy, up air simulation test, foodstaff etc..
Because the fore pump is the 2BV series
water ring vacuum pumps with high efficiency and energy saving, the
JZJ2B series package units are better than the JZJ2S
series. And the JZJ2B series units have some advantages such as high
efficient, compact structure , without leakage, corrosive-proof, higher
protection grade etc.
When the oil is used as the operating liquid of the fore pump, it can
improve the limited vacuum of the unit efficiently.(see the parameter
table). Thus the oil ring package units are closed system, they can decrease
the pollution and save water. They are used extensively in the vacuum
dipping, vacuum dry, and vacuum pumping.
Organic solvent or other liquid can also be used as operating liquid of
the fore pum (for example: methanol, alcohol, xylene,anilin and acetone
whose denseness is lower.). To use the 2BW
series package unit as the fore pump can decrease the environment
pollution and improve the re-claim organic solvent effectively. The limited
vacuum is determined by the saturation steam pressure of the operating
liquid.
How to choose the Roots pump-water ring vacuum pump unit?
Normally, to choose the water ring vacuum pump as the fore pump is better than to choose the others because the following reasons. First, the water ring vacuum pump can pump plentiful coagulable steam. And this advantage is more obviously when use the gas-down and oil seal mechanical vacuum pump as the fore pump because it is poor in pumping the coagulable steam.
Secondly, to use the solvent as the operating liquid will make the oil bad. Sometimes, the system is not allowed the pollution. Furthermore, to choose the package units, it is necessary to make the working vacuum five or ten times of the limited vacuum in order to achieve the best performance of the package units. i.e. working vacuum>=limited vacuum *(5~10).
Several category of the package units
- Roots pump+water ring vacuum pump:The function of the water ring vacuum pump is to form the pre-vacuum for the Roots pump.
- Roots pump+Roots pump+water ring vacuum pump:When use one set of the Roots pump, especially connecting with the water ring vacuum pump, the limited vacuum of the whole unit is much lower with the restricted scope . But to use two sets of the Roots pumps in series and connect them with the water ring vacuum pump can improve the whole limited vacuum effectively.
- Roots pump+Roots pump+Roots pump+water ring vacuum pump:If the two Roots pumps and the water ring vacuum pump unit still dose not satisfie the requirements of the vacuum , another Roots pump can be added. These series Roots units are used extensively in some high vacuum technics of the vacuum freezing or dry process.
Type denotation
For example:J
Z J 2 B 1 5 0 - 2 . 1
J-denotes the first letter in the chinese spelling"ji zu"
ZJ-denotes the main pump using ZJ series Roots pump
2B-denotes the fore pump using the 2BV/2BE series water(or liquid) ring
vacuum pumps
("2S" denotes the fore pump using the 2SK series water (or liquid)
ring vacuum pumps
150-denotes the suction capacity of the main pump (refers the Roots pump)
L/s
2.1-denotes the suction speed ratio among the thre pumps
(i.e. the suction speed ratio between the main and the second pump is
2 and the second and the fore is 1.)