Steel-plastic composite anti-wear plate for water guide sealing structure of water turbine

Abstract

The invention relates to a steel-plastic composite anti-wear plate for a water guide sealing structure of a water turbine. The steel-plastic composite anti-wear plate for the water guide sealing structure of the water turbine comprises a water turbine bottom ring and a water turbine top cover, wherein a bottom ring anti-wear plate assembly is arranged on the upper end surface of the water turbine bottom ring and comprises a plurality of fan-shaped bottom ring anti-wear plate units with the same structures; the bottom ring anti-wear plate units are uniformly distributed along the upper end surface of the water turbine bottom ring; a top cover anti-wear plate assembly comprises a plurality of fan-shaped top cover anti-wear plate units with the same structures; each top cover anti-wear plate unit consists of a first top cover anti-wear plate unit and a second top cover anti-wear plate unit; and the first top cover anti-wear plate units and the second top cover anti-wear plate units are successively and alternately distributed uniformly along the lower end surface of the water turbine top cover.

Description

technical field [0001] The invention belongs to the technical field of sealing the water guiding mechanism of a hydropower station unit, and in particular relates to a steel-plastic composite wear-resistant plate used for the water guiding and sealing structure of a hydraulic turbine. Background technique [0002] The flow surface of the water guide mechanism of the turbine is scoured by high-speed water flow during operation, especially when the water contains a lot of sand, the abrasive damage is very serious, which is a difficult and common problem for the water quality of sandy multi-phase flow and the water turbines of medium and high head hydropower stations. It has endangered the safe and economical operation of power plants for a long time. [0003] In the structural design of the water turbine, the bottom ring of the water guiding mechanism and the flow-through surface of the top cover need to be protected by a special cladding layer, which is an anti-wear plate. T...

AI Technical Summary

Problems solved by technology

However, the wear resistance is not ideal, especially when the sand content is large, the life of this kind of anti-wear plate often limits the overhaul period of the unit

The replacement of the anti-wear plate requires a long shutdown, consumes a lot of materials and labor hours, and causes huge economic losses (maintenance and power outage losses: taking a unit with a capacity of 200,000 kw as an example, the daily power loss is 4.8×10 5 degree, the on-grid electricity price is calculated at 0.3 yuan / kWh, and the loss is 1.44 million yuan per day)

[0004] Through the existing literature search and the actual operation of hydropower stations, it is found that some hydropower stations have used nylon as the bottom ring anti-wear plate instead of metal anti-wear plates. Although the anti-wear ability has been improved to a certain extent, the effect is not obvious; High-density polyethylene is used to make anti-wear plates. Although the anti-wear performance of this anti-wear plate is better than that of nylon, it is easy to deform after long-term use. After soaking in water for 2 to 3 years, it will deform due to water absorption and swelling The enlarged "wedge-shaped gap", resulting in "secondary channeling" in the gap, and the cavitation of the gap and the impact of high-frequency and large angle of attack on the sediment are superimposed, resulting in serious cavitation of the leakage ring of the turbine, threatening the safe operation of the turbine

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