Repair process for cavitation corrosion of runner chamber of through-flow type water turbine

Abstract

The invention discloses a field repair process for cavitation corrosion of a runner chamber of a through-flow type water turbine, which belongs to the field of electromechanical technologies of hydropower stations. The field repair process comprises the following steps: (1) pre-cleaning: cleaning the surface of the part with the cavitation corrosion on the inner wall of the runner chamber; (2) assembly and welding: assembling and welding a support part according to a cavitation corrosion distribution region and reinforcing the part to be welded on the inner wall of the runner chamber; (3) back welding: filling up grooves with more serious cavitation corrosion condition through argon-arc welding one by one; (4) overlay welding: performing overlay welding on a cavitation corrosion belt on the basis of the step (3); (5) postprocessing: detaching the support part in the step (2) after cooling the welded part; and (6) grinding and polishing: grinding and polishing the welded repair surface. The repair process provided by the invention has the advantages of reliability of repair quality, small deformation, long service life of repaired part and applicability to large-area repair of the cavitation corrosion of the runner chamber of the through-flow type water turbine.

Description

technical field [0001] The invention discloses a repairing process, in particular to an on-site repairing process for cavitation in a runner chamber of a tubular water turbine, and belongs to the electromechanical technical field of a hydropower station. Background technique [0002] In the flow channel of the turbine, the cavitation formed by the cavitation of the water flow in the low-pressure area suddenly bursts in the high-pressure area, causing the pressure in the local area to increase suddenly. If the continuously formed and growing cavitation bubbles in the water flow collapse frequently on the wall of the runner chamber, the wall will be repeatedly impacted by huge pressure, which will cause fatigue damage and even surface erosion of the material, which is called the cavitation of the runner chamber. [0003] After many years of operation of the tubular hydroelectric generator set, the cavitation phenomenon in the runner chamber will directly lead to the continuous...

AI Technical Summary

Problems solved by technology

Since the high temperature of the welding arc will cause welding deformation and seriously affect the working quality of the runner chamber, the method of repairing welding with stainless steel materials is not suitable for large-area cavitation repair of the runner chamber, and this method does not adopt corresponding deformation control measures

The process of repairing with viscose materials, because the bonding strength of viscose materials is not as good as that of metal materials, it is easy to peel off and fall off under the impact of water flow, and the operating life of the turbine after repair is limited

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