Impeller Attachment Method

Abstract

A pump is provided having an impeller in combination with a power transmission shaft. The impeller has a tapered bore with impeller threads. The power transmission shaft has a shaft end with tapered threads configured to couple directly to the impeller threads of the tapered bore of the impeller, to transmit torque directly through the tapered threads, and to provide self axial or radial alignment even if the coupling of the tapered threads and the impeller threads of the tapered bore start out of alignment. The tapered thread configuration substantially reduces investment in lifting equipment and time by maintenance personnel because it eliminates the need for maintenance personnel to precisely align the impeller threads and the tapered threads before attaching or removing the impeller and the tapered threads release much more quickly from the impeller than a standard thread configuration, reducing the number of turns the power transmission shaft must be rotated by hand to free it from the impeller.

1 . A pump or pump assembly, arrangement or combination comprising:
 an impeller having a tapered bore with impeller threads; and   a shaft having a shaft end with tapered threads configured to couple directly to the impeller threads of the tapered bore of the impeller, to transmit torque directly through the tapered threads, and to provide self alignment even if the coupling of the tapered threads and the impeller threads of the tapered bore starts out of alignment,   the tapered thread and the impeller threads being configured in combination to substantially eliminate the need to precisely align the impeller threads and the tapered threads before attaching or removing the impeller, and   the tapered threads being configured to release quickly from the impeller threads when compared to a standard thread configuration, reducing the number of turns the shaft must be rotated to be removed from the impeller.   
     
     
         2 . A pump or pump assembly, arrangement or combination according to  claim 1 , wherein the shaft is a power transmission shaft. 
     
     
         3 . A pump or pump assembly, arrangement or combination according to  claim 1 , wherein the self alignment includes an axial or radial alignment. 
     
     
         4 . A pump or pump assembly, arrangement or combination according to  claim 1 , wherein the pump or pump assembly, arrangement or combination includes a slurry-type pump or centrifugal pump. 
     
     
         5 . Apparatus, comprising:
 an impeller having a tapered bore with impeller threads; and   a power transmission shaft having a shaft end with tapered threads configured to couple directly to the impeller threads of the tapered bore of the impeller, to transmit torque directly through the tapered threads, and to provide self alignment even if the coupling of the tapered threads and the impeller threads of the tapered bore starts out of alignment,   the tapered thread and the impeller threads being configured in combination to substantially eliminate the need to precisely align the impeller threads and the tapered threads before attaching or removing the impeller, and   the tapered threads being configured to release quickly from the impeller threads when compared to a standard thread configuration, reducing the number of turns the shaft must be rotated to be removed from the impeller.   
     
     
         6 . Apparatus according to  claim 5 , wherein the self alignment includes an axial or radial alignment. 
     
     
         7 . Apparatus according to  claim 5 , wherein the apparatus takes the form of a pump or pump assembly, arrangement or combination. 
     
     
         8 . Apparatus according to  claim 5 , wherein the pump or pump assembly, arrangement or combination takes the form of a slurry-type pump or centrifugal pump. 
     
     
         9 . Apparatus according to  claim 5 , wherein the apparatus takes the form of rotating machinery or equipment, including a compressor or fan.