A prestressed combined internal cooling mold core and method for hot extrusion forming of a large valve body

Abstract

The invention discloses a prestressed combined mold core and internal cooling method for hot extrusion of a large valve body. The mold core is decomposed into three parts: the core, the core sleeve and the flange. The structure is simple and the processing is convenient. Combined structure, no need for fastener assembly, easy replacement of the core core, improving the overall structural strength and core life of the core core, reducing the manufacturing cost of the core core, and reducing the consumption of molds. The invention also discloses an internal cooling method for a prestressed combined mold core formed by hot extrusion of a large valve body. A spiral and paper clip cooling channel is set between the core and the core sleeve, and the cooling water or compressed air is passed through the core sleeve. Introduced into the paperclip cooling channel at the flange, and then out of the core sleeve along the tapered spiral cooling channel, it can effectively reduce the temperature of the core during hot extrusion, avoid early failure of the core, and improve the quality of the core. life. Adopting the cooling method of the invention can effectively improve the fluidity of the metal, and improve the filling and forming quality of the metal.

Description

technical field [0001] The invention belongs to the technical field of plastic forming of metal materials, and in particular relates to a prestressed combined internal cooling mold core and a method for hot extrusion forming of a large valve body. Background technique [0002] The large three-way valve body with left and right double flanges is a key component of high-end valves in oil and gas wellhead devices and Christmas tree equipment. The traditional production method mainly adopts the free forging method. The forgings are fat and big, and a large amount of material needs to be removed by machining to obtain the flange and inner shape structure of the valve body. The material utilization rate is low, and the metal flow line of the product is not continuous. The service life is low; when the die forging method is used, although the above situation can be improved, it is full of difficulties for the double flange die chamber of the large valve body, which is prone to fold...

AI Technical Summary

Problems solved by technology

The mold core is generally of integral structure, heavy, expensive material, complex cavity, and difficult manufacturing process. At the same time, due to the direct contact time between the high-temperature blank and the inside of the mold core for as long as 30 seconds, the mold core is heated violently, coupled with high temperature The strong friction and extrusion of metal, complex internal and external forces, and extremely uneven stress distribution can easily cause high-temperature wear, collapse, deformation or local melting and thermal cracks inside the mold core, resulting in the scrapping of the entire mold core, thus reducing production costs. a higher proportion of

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