Changsha Zoomlian pump industry independently designed and produced the multistage pump design widely used in the current market is mainly divided into two categories: one is the D-type standard multistage pump, whose impeller is linearly arranged, whether from left to right or the opposite direction; The other is the DP series self-balancing multistage pump, which automatically balances the axial force through the impeller arranged in the positive and negative directions. Both pump types start with the first stage impeller of a single suction or specific pump head, followed by a multi-stage centrifugal structure of a single suction impeller.
In addition, there are also multistage centrifugal pumps with full double suction impellers constituting a rotor system, which are specially designed with double suction. For multistage pumps with double impellers, the flow channel design is complex and difficult to implement, so the number of double impellers is usually limited to 2 to 3 pieces.
Type D and type DG multistage centrifugal pumps use sequential impeller, the medium flows from one end, after each level of impeller pressure from the other end of the outflow. The DK two-stage Split Case Pump achieves axial force self-balance on the impeller through the open design, and the medium enters from one end, is connected to the other end through the internal conduit in the middle position, and finally discharged from the middle outlet. To meet the challenge of high pressure sealing, these pumps often need to be equipped with a balanced pipe decompression and a sealing device in the high and low pressure area, but this sacrifices some pump efficiency and increases volume.
In response to the above problems, the technical team of Hunan Lishende energy-saving pump industry has developed a new type of double-import self-balancing multistage pump. The core feature of this pump is that the outlet in the middle position corresponds to the double-suction impeller, the two inlet are located at both ends of the pump, the double-suction impeller between the multistage impeller is symmetrical layout with the outlet as the center, which can effectively improve the suction range of the pump, so that the cavitation phenomenon is more difficult to occur, at the same time, this pump has no throttling sleeve design, for later maintenance, the cost is more controllable. It's also more convenient.
The new double-inlet self-balancing multistage centrifugal pump is divided into two types: segmented type (characterized by both ends of the guide vane and the middle volute outlet) and integrated type (the pump body itself as the volute). Since both ends are inlet, the medium is not pressurized, so there is no high pressure end, no balancing tube is required. At the same time, the symmetrical arrangement of the double-suction impeller at the outlet naturally balances the axial force, reduces the need for sealing devices in high and low pressure areas, reduces leakage, and avoids the space lost by the traditional multistage pump due to the balancing device and sealing device.
This not only improves efficiency, saves materials, but also extends continuous operation time, and its structure is more concise than the single-suction multistage pump, which is easy to maintain later.