Patent 9243646 was granted and assigned to Grundfos on January, 2016 by the United States Patent and Trademark Office.
An impeller (2) for a centrifugal pump includes a first shroud having a plurality of blades (8). A second shroud is joined onto the first shroud by way of welding. Each blade (8) has an apex region (12), at which the blade contacts the second shroud. At least one of the blades (8) in a first section (20) of the apex region (12) has a weld connection to the second shroud, and in at least one second section (14) of the apex region (12) is free of a weld connection.