CN1322948C

CN1322948C - Mould and method for preparation high-pressure switch cast aluminium can

Info

Publication number: CN1322948C
Application number: CNB2004100502907A
Authority: CN
Inventors: 李荣德; 侯峻岭; 陆启为; 于海朋
Original assignee: NEW NORTHEAST ELECTRIC(SHENYANG)HIGH VOLTAGE SWITCHGEAR CO Ltd; Shenyang University of Technology
Current assignee: NEW NORTHEAST ELECTRIC(SHENYANG)HIGH VOLTAGE SWITCHGEAR CO Ltd; Shenyang University of Technology
Priority date: 2004-08-20
Filing date: 2004-08-20
Publication date: 2007-06-27
Anticipated expiration: 2024-08-20
Also published as: CN1597179A

Abstract

The present invention relates to a mold and a process for preparing high-voltage switch cast aluminum pots, which belongs to the integration forming of metal. The present invention provides a low-pressure casting method by a metal model in order to solve the problem that the present sand mold low-pressure casting method for production has poor product quality and low efficiency and qualification rate, wherein a guide port, a direct pouring channel and a cap port connected with a riser tube is arranged on the mold; a transverse pouring channel and an annular inner pouring port connected with the transverse pouring channel are arranged on a sand core; pressure injected into a mold cavity by the molten metal is gradually increased to 5000 to 8000KPa step-by-step. Thus, compared with the prior art, both the quality and each physical chemistry index of products are correspondingly increased and meet the technical requirements of high-voltage transmission and distribution, and the present invention has the advantages of low cost and high rate of finished products.

Description

The mould and the method for preparation high-voltage switch gear cast aluminium jar

Technical field

The present invention relates to a kind of metal forming process,, adopt the mould of method and employing this method of aluminium alloy casting moulding especially about high-voltage switch gear sealing SF6 metal can.

Background technology

At present, about producing the method for high-voltage switch gear sealing SF6 metal can, most Japan's methods with the moulding of steel plate assembly welding commonly used that adopt, the tank body that this method is produced is big, quality big, poor, the cost height of rotproofness, add the production routine complexity, size and surface quality are difficult for guaranteeing that the finished product rate is low; People are in order to address the above problem, occurred employing aluminium alloy monoblock cast new method in recent years, but majority is to use conventional sand casting process, the result is that surface quality is poor, organize not fine and close, pore, cinder hole are more, and resistance to pressure descends, poor air-tightness, production efficiency is low, qualification rate is low, and the production cost height is difficult to satisfy tensile strength 220～300kg/cm ², percentage elongation 1～4%, withstand voltage＞4.0MPa, leak rate＜1ugSF6/m ²S and surface smoothness 〉=technical requirements such as Re150 μ m.

Summary of the invention

At above-mentioned weak point, the invention provides that a kind of to satisfy tensile strength be 220～300MPa, percentage elongation is 1～4%, withstand voltage＞4.0MPa, leak rate＜1ugSF6/m2s and surface smoothness reach 〉=technical requirements such as Re150 μ m, and dense structure, withstand voltage anti-corrosion, the geometry complete and accurate, finished product qualification rate height, the mould and the method for preparation high-voltage switch gear cast aluminium jar.

The technical solution adopted for the present invention to solve the technical problems is: adopt metal die and low-pressure casting method to make its product Integratively formed, the mould that wherein prepares high-voltage switch gear cast aluminium jar, it includes mould crust and core, mould crust is provided with the introducing port that links to each other with the crucible stalk, link to each other with this mouthful and to be located at the sprue of its underpart, little flange place, mould upper end is provided with the cap mouth, and this cap mouth communicates with die cavity; Core is provided with to communicate with sprue and occupies the cross gate of left and right end, communicates with cross gate, prolongs its cross gate and moves towards direction and be furnished with circular gate.

Wherein, in mold cavity during cast aluminium, make the molten metal injection pressure progressively be raised to 50～80KPa, and be divided into: rise the liquid stage, fill the type stage, crust stage, pressurization stages, pressurize crystallization stage, release stage, the method of operating of each section period and pressure oscillation is to rise the liquid stage in 25～35 second time, and relative pressure increases by 25～35KPa; Fill the type stage in 40～50 second time, pressed relative pressure increase by 10～20KPa on the basis in last stage Mo; The crust stage kept that to fill type stage Mo pressure value constant in 1～5 second time; Pressurization stages relative crust stage Mo pressure in 3～9 second time increases by 15～25KPa; Crystallization stage was kept pressurization stages end pressure value in 150～300 second time constant.

The invention has the beneficial effects as follows: method is workable, makes things convenient for parameter control, the product surface quality height of especially producing, and yield rate rises, anti-corrosion good pressure-resistant performance, every high-voltage electrical apparatus engineering index all can meet the demands, and cost is low.

Description of drawings

Below in conjunction with accompanying drawing, the invention will be further described:

Fig. 1 is a production method flow chart of the present invention;

Fig. 2 is that the mould master looks the cross-section structure principle schematic in Fig. 1 method;

Fig. 3 is a mould left side sectional structure principle schematic among Fig. 2;

Fig. 4 is a casting method operating procedure curve map in Fig. 1 method;

Among the figure: 1 chill, 2 ingates, 3 sprues, 4 introducing ports, 5 rising heads, 6 cross gates, 7 moulds, 8 cores

The specific embodiment

The mould of preparation switch cast aluminium jar is to make with metal material, and its structure is shown in Fig. 2,3.Its mould crust is provided with the introducing port 4 that links to each other with the crucible stalk, the sprue 3 that links to each other with this mouthful and be located at its underpart, and little flange place, mould upper end is provided with cap mouth 5, and this cap mouth 5 communicates with die cavity; Core 8 is provided with the cross gate 6 that communicates and occupy left and right end with sprue 3, communicates with cross gate 6, prolongs its cross gate 6 and moves towards direction and be furnished with circular gate 2.Consider that foundry goods reaches certain density and relevant metallographic crystallization process brings good effect to product quality, its casting method and step are as shown in Figure 1.

The operating procedure of casting method promptly is divided into and rises the liquid stage as shown in Figure 4, fills the type stage, the crust stage, pressurization stages, crystallization stage and release stage, more than the method for operating of each time in stage and pressure variation be: rise the liquid stage in 25～35 second time, relative pressure increases by 25～35KPa; Fill the type stage in 40～50 second time, pressed relative pressure increase by 10～20KPa on the basis in last stage Mo; The crust stage kept that to fill type stage Mo pressure value constant in 1～5 second time; Pressurization stages is in 3～9 second time, and the stage pressure that crusts relatively increases by 15～25KPa; Crystallization stage is in 150～300 second time, and it is constant to keep pressurization stages end pressure value, and this stage finishes the back release, takes out foundry goods.

Each time in stage and pressure change to the production different wall product parameters select as table:

Claims

1, a kind of mould for preparing high-voltage switch gear cast aluminium jar, include mould crust and core, it is characterized in that mould crust is provided with the introducing port that links to each other with the crucible stalk, linking to each other with this mouthful is located at the sprue of its underpart, little flange place, mould upper end is provided with the cap mouth, and this cap mouth communicates with die cavity; Core is provided with to communicate with sprue and occupies the cross gate of left and right end, communicates with cross gate, prolongs its cross gate and moves towards direction and be furnished with circular gate.

2, application rights requires 1 described mould to prepare the method for high-voltage switch gear cast aluminium jar, include giving the ingot metal fusing, insulation, low pressure casting step is characterized in that the molten metal injection pressure progressively is raised to 50～80KPa, and be divided into: rise the liquid stage, fill the type stage, crust stage, pressurization stages, the pressurize crystallization stage, in the release stage, the parameter of each section period and pressure oscillation is: rise the liquid stage in 25～35 second time, relative pressure increases by 25～35KPa; Fill the type stage in 40～50 second time, pressed relative pressure increase by 10～20KPa on the basis in last stage Mo; The crust stage kept that to fill type stage Mo pressure value constant in 1～5 second time; Pressurization stages relative crust stage Mo pressure in 3～9 second time increases by 15～25KPa; Crystallization stage was kept pressurization stages end pressure value in 150～300 second time constant.