Welded impeller of canned motor pump used for central air conditioner

Abstract

The invention relates to a welded impeller of a canned motor pump used for a central air conditioner. The impeller comprises a front cover plate and a rear cover plate which are matched correspondingly, wherein long blades and short blades in spiral radial shapes are uniformly distributed on the inside surface of the rear cover plate; each short blade is positioned between two adjacent long blades; six straight blades are uniformly distributed on the outside surface of the rear cover plate; welding process holes are uniformly formed on the rear cover plate; the welding process holes are uniformly formed on the front cover plate correspondingly; the welding process holes on the front cover plate and the welding process holes on the rear cover plate are all provided with welding fluxes; and an integrated impeller is formed by welding. In the welded impeller, the front cover plate and the rear cover plate of the impeller are cast separately, which solves a difficult casting problem of the impeller with large impeller diameter and small egress width. The egress width of the impeller of the invention is only 3mm; the outside diameter of the impeller is over phi160mm; the efficiency of a pump is up to 20 percent; and the net positive suction head is below 0.45mm. The welded impeller improves the efficiency of the pump greatly. A small-flow high-lift lithium bromide canned motor has the characteristics of high efficiency and anti-cavitation performance.

Description

technical field [0001] The invention belongs to the technical field of shielded electric pumps, in particular to an impeller of a shielded electric pump for central air conditioning. Background technique [0002] Lithium bromide central air-conditioning canned electric pumps operate under high vacuum conditions, so they require good air tightness, high anti-cavitation performance, and relatively high efficiency in order to save energy. Small flow and high head pumps theoretically require a larger impeller outer diameter and a narrower outlet width. Larger impeller outer diameters and narrower outlet widths cannot be achieved in casting, so the performance requirements of small flow and high head must be met or With open impellers, such as Figure 7 and Figure 8 In the design method shown, the blades are radioactive straight blades, and the anti-cavitation performance meets the requirements, but the efficiency is generally low; or the design of increasing the flow rate is a...

AI Technical Summary

Problems solved by technology

Small flow and high head pumps theoretically require a larger impeller outer diameter and a narrower outlet width. Larger impeller outer diameters and narrower outlet widths cannot be achieved in casting, so the performance requirements of small flow and high head must be met or With open impellers, such as Figure 7 and Figure 8 In the design method shown, the blades are radioactive straight blades, and the anti-cavitation performance meets the requirements, but the efficiency is generally low; or the design of increasing the flow rate is adopted to artificially increase the width of the impeller outlet, and the flow rate of the high efficiency point of the pump is much higher than that of the pump working Point flow, high-efficiency point flow is too large, the actual efficiency of the pump's working flow point is still very low

Images