Chill-free processing method of wind-driven generator hub

Abstract

The invention discloses a chill-free processing method of a wind-driven generator hub, and the method comprises the following steps: manufacture of a mould, manufacture of a sand mould and moulding by casting, wherein in the manufacture of the sand mould, a completely opened bottom gating system is utilized; an ingate is designed to be disc-shaped; a downgate on an upper sprue is a quantitative ladle stopper sprue gate; the ratio of the components is F(straight):F(transverse):F(internal)=1:(1.5-2):(25-28); a rectangular vent hole is arranged at the highest point at the top face of a casting; the total section area of the rectangular vent hole is greater than that of the ingate; a casting head is arranged on the top face of the casting; the height of the single casting head is greater than 400 mm; no chills are discharged during the manufacture procedure; in the moulding by casting, the casting speed of melted iron entering into a casting cavity is controlled within 0.5-1.0 m/s; the casting time is controlled within 150-210 seconds; and the casting temperature is between 1300 and 1310 DEG C. The chill-free processing method of the wind-driven generator hub disclosed by the invention has the advantages that the method adapts to the large scale production of low-temperature ductile iron castings for large wind-driven generator with quite high requirements, the process is simple, and the production cost is low.

Description

technical field [0001] The invention relates to the technical field of wind power generator sets, in particular to a chill-free processing method for a wind power hub in a wind power generator set. Background technique [0002] Wheel hub castings are large and complex parts in wind turbines (such as JF1500 hub castings, casting grade: QT400-18AL, casting weight: 7300kg, maximum casting size: 2600×2300×1710㎜), it is a number of parts The carrier of the components is the key component of the wind turbine, and it is suitable for complex and variable loads during operation. Therefore, the requirements are extremely strict, and the quality of the hub is one of the bottlenecks restricting the development of wind power above the MW level. However, the traditional casting method of adding cold iron and increasing the riser (the riser is very large, and the diameter of the riser is generally 1.3 to 1.5 times larger than the hot pitch circle) is very easy to produce a large number of...

AI Technical Summary

Problems solved by technology

However, the traditional casting method of adding cold iron and increasing the riser (the riser is very large, and the diameter of the riser is generally 1.3 to 1.5 times larger than the hot pitch circle) is very easy to produce a large number of surface defects and internal defects on the hub. For example, in the actual production according to the original process method, a circle of 200×100×80 cold iron needs to be placed on the blade mounting surfaces of the three sides of the hub, and some forming cold irons should also be placed at the transition between the upper plane and the rounded corners of the ribs. In the actual sand setting operation, four people are required to place the cold iron, and the unevenness of the cold iron placed not only has a great impact on the appearance quality of the casting, but also the weight of the casting will go into tolerance, and the production efficiency cannot be improved. The appearance quality of castings cannot be effectively controlled

The existence of these defects can no longer adapt to the large-scale production of low-temperature ductile iron castings for large-scale wind power with extremely high requirements.

Moreover, the above-mentioned traditional casting method of adding chilled iron and increasing the riser also has the disadvantages of complicated processing technology and high production cost.

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