Process for casting U-shaped frame of wind power generation equipment

Abstract

The invention relates to a process for casting a U-shaped frame of wind power generation equipment. The process is carried out according to the following steps of: (a) smelting; (b) nodularization-inoculation treatment; (c) modeling, core making, steel tube arrangement, core placement and mould assembly; (d) casting; and (e) unpacking, posttreatment, inspection and warehousing. In the process, the horizontal modeling and vertical casting technology are adopted, and a bottom gate casting system is designed so as to ensure the internal quality of castings; slot holes of the castings are directly cast by adopting the method of inlaying cast-steel pipes so as to reduce hot spots of the castings, and the cooling rate of the castings is high so that the internal density and the nodularization quality of the castings can be increased; a cold drawn seamless steel pipe is adopted, the surface is processed by shot blast or sand blast, and the casting temperature of molten iron ranges from 1350 DEG C to 1380 DEG C, thereby ensuring the better fusion between the steel tube and a casting body, and simultaneously greatly reducing the workload of post machining, reducing working procedures and increasing the production efficiency; and nodularization treatment is carried out by adopting heavy rare earth nodulizer, and inoculation treatment is carried out by adopting special long-acting inoculant, thereby further ensuring the nodularization quality of the castings.

Description

technical field [0001] The invention relates to a casting process, in particular to a casting process for a U-shaped frame of a wind power generating equipment. Background technique [0002] With the rapid development of wind power generation technology, the demand for wind power equipment products is rapidly expanding. The U-shaped frame is one of the important parts of wind power equipment. The internal quality of the castings is high. The original casting process is: For pouring, 8 long holes of ￠44×480mm are not cast out, and are formed by machining and drilling, so that the wall thickness of the casting is relatively thick, resulting in relatively large thermal joints. In order to prevent shrinkage and porosity defects in the casting, There are two thermal insulation and heating risers in the hot section. The casting blank cast by this process, 8 long holes of ￠44×480mm need to be machined. In addition, two heat-insulating and heating risers of each type need to be imp...

AI Technical Summary

Problems solved by technology

[0002] With the rapid development of wind power generation technology, the demand for wind power equipment products is rapidly expanding. The U-shaped frame is one of the important parts of wind power equipment. The internal quality of the castings is high. The original casting process is: For pouring, 8 long holes of ￠44×480mm are not cast out, and are formed by machining and drilling, so that the wall thickness of the casting is relatively thick, resulting in relatively large thermal joints. In order to prevent shrinkage and porosity defects in the casting, There are two thermal insulation and heating risers in the hot section. The casting blank cast by this process needs to be machined with 8 long holes of ￠44×480mm. In addition, each type of heat-insulating and heating riser needs to be imported from abroad, the order cycle is long, the cost is high, and sometimes the failure to arrive on time affects production

In addition, due to the thick wall thickness of the casting, the modulus of the hot section reaches 4.8, and the use of heat preservation and heating risers makes the solidification period of the central part long and the cooling rate slow, resulting in unstable spheroidization levels, sometimes failing to meet the acceptance requirements of castings, resulting in Casting scrap