JPH0521198U - Structure of multi-stage centrifugal compressor - Google Patents

Abstract

(57) [Summary] [Purpose] With a structure that improves the efficiency of the multi-stage centrifugal compressor,
Each stage impeller has the performance as designed, the expected efficiency, and the power has the effect as guaranteed. A heat insulating material is filled in a portion of a partition plate of a multistage centrifugal compressor where a fluid outlet side passage and a fluid inlet side passage are formed back to back.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure for improving the efficiency of a multi-stage centrifugal compressor.

[0002]

[Prior Art]

 The multi-stage centrifugal compressor for increasing the pressure of gas sequentially increases the pressure by the multi-stage centrifugal impeller, and when the temperature rise limit accompanying it is reached, the fluid is once guided to the outside of the compressor and the intermediate cooler is used to bring it to near normal temperature. It is cooled until it is introduced into the compressor again, and compression is repeated until the required pressure is increased.

In the structure of a centrifugal compressor, a multi-stage centrifugal impeller is fitted on a shaft, a partition plate separates adjacent impellers from each other, and the fluid is pressurized by the impeller and discharged in the centrifugal direction. The discharged fluid is guided in the centrifugal direction by the passage formed by the partition plate, the operating energy is recovered as pressure, and U-turned again to be sucked into the next impeller.

In such a structure, the inlet passage and the outlet passage of the partition plate are back-to-back, and heat transfer between the inlet passage side and the outlet passage side cannot be avoided. In particular, the temperature difference is large at the wall surface portion of the passage where the fluid reaches the limit of temperature rise and is guided to the intercooler and where the cooled fluid is again guided to the compressor, and the heat transfer becomes severe.

[0005]

[Problems to be solved by the device]

 There is a temperature difference in the heat transfer on the wall of the partition plate that separates the adjacent inlet / outlet passages, especially when the heat is transferred to the intercooler at the temperature rise limit, cooled to near room temperature, and then guided to the compressor again. Since it is large, it becomes violent, and the temperature of the fluid that has been cooled is raised by the heat, and the compression ratio as theoretically designed cannot be obtained.

Inability to obtain the compression ratio as designed also affects the fluid volume, and the fluid volume of the impeller is unique to the air column height, so the suction volume to the next stage is the design point. It becomes a mismatching. Then, each of the multi-stage impellers accumulates the mismatching in sequence, so the influence on the efficiency becomes very large and the power exceeds the design value. The present invention has been made to solve this drawback.

[0007]

[Means for Solving the Problems]

 The present invention solves the above-mentioned conventional problems, and blocks the transfer of heat from the outlet side fluid to the inlet side fluid at the location where the fluid outlet side passage and the fluid outlet side passage of the partition plate are formed back to back. This is the structure of a multi-stage centrifugal compressor filled with a heat insulating material.

The partition plate filled with the heat insulating material is either a full-stage partition plate having the corresponding portion or a partition plate having a large temperature difference between adjacent fluids.

[0009]

[Action]

 By filling the part of the partition plate where the fluid outlet side passage and the fluid inlet side passage are formed back to back with a heat insulating material, the heat transfer due to the temperature difference between the fluid on both sides is largely blocked. Therefore, the temperature condition as designed is maintained, the compression ratio and the fluid volume become as designed, and the suction point is sucked at the design point volume of the impeller of the next stage, and the air column height as designed for the volume is obtained. Mismatching is eliminated and performance and efficiency as designed can be obtained.

[0010]

【Example】

 An embodiment of the present invention will be described with reference to FIG. The first-stage impeller 1, the second-stage impeller 2, and the third-stage impeller 3 are fitted on the main shaft 4 to form a rotor. Partition plates 6, 7, 8 and 9 supported by a casing 5 are arranged on both sides of the stage impellers 1, 2 and 3 to partition the stage impellers 1, 2 and 3.

The fluid is sucked in from the suction port A in the direction of the arrow, enters the first-stage impeller 1, is given motion energy and is discharged in the centrifugal direction, and is pressurized in the passage formed by the partition plates 6 and 7. , Makes a U-turn, enters the entrance passage of the partition plate 7, and enters the second-stage impeller 2. Similarly, the second stage impeller 2 similarly raises the pressure to reach the pressure increase limit, and then it comes out from the intermediate discharge port B of the casing 5 and is cooled to near room temperature by an intermediate cooler (not shown). It returns from the suction port C into the compressor, and is sucked into the third-stage impeller 3.

In such a gas flow, the heat insulating material 10 is filled in the part of the partition plate 7 where the inlet passage and the outlet passage of the second-stage impeller 2 face each other. The temperature of the fluid discharged from the second-stage impeller 2 is prevented from rising through the partition plate 7 as the temperature of the fluid on the inlet side increases.

Similarly, the fluid that returns from the intercooler to the intermediate suction port C and is sucked into the third-stage impeller 3 depends on the temperature of the fluid discharged from the second-stage impeller 2 or the third-stage impeller. A heat insulating material 10 is filled inside the passage wall of the partition plate 8 so that the temperature does not rise due to the temperature of the discharged fluid of No. 3.

[0014]

[Effect of the device]

 Since the present invention has the above-mentioned structure, it is possible to block the heat transfer of the fluid flowing back to back of the multi-stage centrifugal compressor, and each stage impeller is sucked at the designed temperature. Therefore, each stage impeller can perform as designed, achieve the expected efficiency, and achieve the power required. The effect of improving reliability for performance is remarkable.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a multi-stage centrifugal compressor according to an embodiment of the present invention.

[Explanation of symbols]

 1 1st-stage impeller 2 2nd-stage impeller 3 3rd-stage impeller 4 Spindle 5 Casing 6, 7, 8, 9 Partition plate 10 Insulation material A Suction port B Intermediate discharge port C Intermediate suction port

Claims (1)

[Scope of utility model registration request] 1. A part of the partition plate where the fluid outlet-side passage and the fluid inlet-side passage are formed back to back is filled with a heat insulating material for blocking heat transfer from the outlet-side fluid to the inlet-side fluid. And the structure of the multi-stage centrifugal compressor.