Casting device and process for large 90-degree pressure-resistant aluminum alloy bend shell of extra-high pressure GIS switching equipment

Abstract

The invention relates to a casting device and process for a large 90-degree pressure-resistant aluminum alloy bend shell of extra-high pressure GIS switching equipment. The bend shell is of a 90-degree bend structure, flanges are arranged at the two ends of the bend shell, and the bend shell comprises a sand core lifting structure and a core box. The sand core lifting structure comprises a lifting hook, an embedded support connected with the lifting hook and a thick nut connected with the lifting hook and the embedded support. The core box is provided with a containing groove for containing a sand core, a notch for containing the lifting hook and a through hole allowing the containing groove and the notch to be communicated. The lower end of the embedded support of the sand core lifting structure is of a cross-shaped structure for locating two flange parts of the sand core respectively. The exact center of the upper portion between the two flanges of the sand core is located through the lifting hooks. An inner casting channel of the sand core comprises multiple vertical barrels connected with transverse casting channels and casting gates. By the adoption of the device and process, part casting quality can be improved, and it is guaranteed that parts receive the pressure of the hydraulic pressure destructive test requirement.

Description

technical field [0001] The invention relates to a low-pressure casting device for aluminum alloy castings and a process thereof, in particular to a low-pressure casting process applied to manufacturing large-scale pressure-resistant aluminum alloy casting shells for key parts of UHV GIS switchgear. Background technique [0002] The UHV power grid has the characteristics of large capacity, long distance and low loss power transmission, which can greatly improve the transmission capacity of my country's power grid. The UHV GIS switchgear is a national key development project. The aluminum alloy casting shell involved in the present invention is the product of this product. One of the key parts, these parts are large-scale shell castings. At present, the manufacturing method mostly adopts the gravity casting process, and the material used is the cast aluminum alloy ZL101A with a high tendency of oxidation and pinholes, so the casting process is difficult. Therefore, it is necessa...

AI Technical Summary

Problems solved by technology

In order to ensure the filling, degassing and slag discharge of molten aluminum, the two gates YJ01 and YJ02 adopt a gap-type pouring system, but they must be poured at the two gates YJ01 and YJ02 at the same time during pouring, which is inconvenient to operate, and the two gates The pouring speed of the gate cannot be kept consistent, which will lead to poor casting quality; for this process, a filter must be designed at the bottom of the gate, but the placement of the filter is very difficult; The way to solve the problem that the main core of the bent tubular core is unstable, and the core is easy to be partial after the core is placed, but the problem of lifting the sand core is not considered

The castings produced have been inspected in all aspects. The main problem is that the pressure of the hydrostatic destructive test cannot meet the design requirements.

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