The invention provides a high-flow-rate ultra-large-
diameter semi-milling and semi-
welding closed ternary
impeller and a manufacturing method. The closed ternary
impeller mainly comprises a wheel cover, a wheel disc and a blade, wherein the blade is uniformly divided into two halves, one half of blade is integrally milled and formed with the wheel cover, the other half of blade is integrally milled and formed with the wheel disc, in addition, the two halves of blades are welded at a
butt joint part for forming an integral blade, a groove is formed in the
butt joint part of the two halves of blades, and in addition, a
welding seam is formed in the middle of the whole blade after the
welding. The manufacturing method comprises the following steps that the blade of the ternary
impeller is uniformly divided into two parts, one half of blade is integrally milled into the wheel disc, one half of blade is integrally milled into the wheel cover, the groove is formed in the
butt joint part of the two halves of the blades, in addition, the whole blade is welded after the fixation by a tooling, and the welding seam is formed in the middle of the whole blade; after the welding of the wheel cover and the wheel disc of the impeller is completed, the stress is eliminated, and the outer contour of the impeller is finely turned in the turning
processing center of a
numerical control machine tool after the re-installing and re-clamping; finally, the welding part of the blade is manually ground to be smooth. The ternary impeller and the manufacturing method have the characteristics that better pneumatic performance and pneumatic efficiency are realized, the
processing quality is good, the impeller intensity is high, and the like.