Centrifugal compressors impellers

Eckhardt, D., Instantaneous Measurements in the Jet-Wake Discharge Flow of a Centrifugal Compressor Impeller, ASME Paper No. 74-GT-90. 

Figure 5-34. A fabricated centrifugal compressor impeller. Courtesy ofA-C Compressor Corporatiofi ...

Centrifugal compressor impellers, with the exception of the open impeller, are thrust unbalanced. The machine also has a requirement for a location device to maintain axial clearances. For these reasons, all centrifugal compressors use some form of thrust bearing. 

Impeller Fabrication Centrifugal-compressor impellers are either shrouded or unshrouded. Open, shrouded impellers that are mainly used in single-stage applications are made by investmentcasting techniques or by three-dimensional milling. Such impellers are used, in most cases, for the high-pressure-ratio stages. The... 

Centrifugal Compressors The flow in a centrifugal compressor enters the impeller in an axial direction and exits in a radial direction. 

Stanitz, J.D. and Prian, V.D., A Rapid Approximate Method for Determining Velocity Distribution on Impeller Blades of Centrifugal Compressors, NACA TN-2421, 1951. 

Calibrated pressure drops from the inlet flange to the eye of the firststage impeller in centrifugal compressors, when such data is available from the manufacturer. 

The radial-flow, or centrifugal compressor is a widely used comj sor and is probably second only to the reciprocating compressor in usage in the process industries. A typical multistage centrifugal compressor can he seen in Figure 1-11. The compressor uses an impeller consisting of... 

Obviously this test applies only to the centrifugal compressor. The manufacturer normally performs this test whether specified or not. Since the user does have an interest in the test, some discussion of the parameters is in order. API 617 mandates the test, which includes the requirement to spin the impeller at a speed of 115% of the maximum continuous speed for a duration of one minute. 

Similar to multistage centrifugal pumps, centrifugal compressors, as shown in Figure 10-9, use a series of rotating impellers to impart velocity... 

The impellers for centrifugal compressors are assemblies consisting of three parts the hub disc, the blades, and the cover disc. The hub and cover disc are machined from single-piece forgings of an alloy steel suitable for the application of the compressor. Blades are machined from forged steel plates of identical material. Each forging is checked with either sonic or X-ray machines to detect flaws or inclusions. 

Figure 12-46F. Open radial blade impeller, Type R. (Used by permission Bui. Centrifugal Compressors Single Stage. A C Compressor Corporation.)...

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