CN105397026A - Casting process for forming complex pipeline in titanium alloy investment casting - Google Patents

Abstract

The invention discloses a casting process for forming a complex pipeline in a titanium alloy investment casting; and the process comprises the steps of: preparation of a pipe, parting and manufacturing of a wax mold, combination of the wax mold, roasting after steam dewaxing, and casting after laying a titanium pipe in a mold shell. The pipe formed by the process has no gap with a main body; the sealing and pressure resisting requirements of the pipe can be satisfied; the formation of the pipe is more flexible compared with a ceramic core and direct coating; the forming process requirements of pipes with various shapes of castings can be satisfied; the casting process difficulty is reduced; after the process is performed, the defects of cleaning difficulty and use limit are overcome, the casting surface quality is guaranteed, the production period is shortened, and the casting production cost is saved; and as the titanium pipe is inlaid after high-temperature roasting of the mold shell, the deformation in the casting process is reduced, and the casting quality is further improved.

Description

A kind of casting technique forming complex pipeline in titanium investment foundry goods

Technical field

The present invention relates to investment pattern precision casting field, particularly relate to a kind of casting technique forming complex pipeline in titanium investment foundry goods.

Background technology

In existing titanium investment castings production technology, traditional titanium alloy casting pipeline forms the main method adopting core moulding.The position that diameter >=φ 20 and flexibility are greater than 90 degree is no more than a place, generally takes the method for direct paint case making to be formed; Diameter is between φ 10 and φ 20, and length≤100 and the bending position being greater than 90 degree are no more than the better simply pipeline at two places, generally adopt ceramic core; For the long pipeline that diameter≤φ 10 is complex-shaped, above two kinds of process programs there will be following problem in actual mechanical process: the ceramic core and the formwork not easy-clear that 1, form pipeline, in the process of cleaning, easily damage inner-walls of duct; 2, core easily ruptures and core shift under the fierce impact of titanium liquid, causes uneven, the deficient casting of foundry goods pipeline wall thickness and runout; 3, ceramic core is difficult to locate in a mold, easily eccentric or fracture; 4, the coating cleaning in the complex pipeline formed by coating is very difficult, substantially cannot realize; 5, in the wax-pattern stage titanium pipe is embedded in relevant position or directly titanium pipe placed in a mold directly casting and form wax-pattern, when later stage formwork high-temperature roasting, titanium pipe is easily oxidized, cracking etc., cause the foundry goods of cast defective.

Summary of the invention

In order to solve the problems of the technologies described above, the present invention aims to provide one

The present invention is achieved by following technical solution:

4, in titanium investment foundry goods, form a casting technique for complex pipeline, it is characterized in that its processing step is:

(1) pipeline is made into the shape of needs, in pipeline, fills up yttrium oxide sand, pipeline opening waterglass aluminum mixture vanadine mud is blocked;

(2) by pipeline somatotype, and press somatotype making main body wax-pattern, split wax-pattern and cover plate wax-pattern, Split mold comprises bonding wax-pattern;

(3) bonding wax-pattern and main body wax-pattern are bonded together, make overall shell with after the roasting of main body wax-pattern steam dewaxing high-temperature vacuum; Split cover plate wax-pattern is made shell separately;

(4) shell is pressed vacuum≤10Pa after steam dewaxing; Temperature: 1050 ± 20 DEG C; Be incubated 3 ~ 5 hours after roasting, be cooled to less than 180 DEG C to come out of the stove with stove;

(5) pipeline made is inserted in roasting shell, split cover plate wax pattern shell and pipeline are located, then remove moisture with blowtorch baking, be combined into integrated poured shell;

(6) integrated poured shell is carried out preheating, cast, the foundry goods after cast, walk operation by the technological process of general precision-investment casting.

Yttrium oxide sand in described step (1) is 100 order sand.

In described step (2), body die needs to offer location in mind, prevent titanium pipe eccentric under molten metal impulsive force and centrifugal action.

The invention has the beneficial effects as follows:

Compared with prior art, a kind of casting technique forming complex pipeline in titanium investment foundry goods provided by the invention, gapless between the pipe of formation and body, can meet the sealing of pipeline and withstand voltage requirement; This process program forms pipeline and forms pipeline more flexibly relative to ceramic core and direct coating, can meet the pipeline forming technological requirement of the various shape of foundry goods, reduces casting manufacturability difficulty; After implementing this process program, overcome cleaning difficulty, use restricted shortcoming, ensure that surface quality of continuous castings, shorten the production cycle, saved castings production cost; Due to titanium pipe-inserted again after formwork high-temperature roasting, decrease the deflection in casting process process, the quality in kind of foundry goods obtains further raising.

Accompanying drawing explanation

Fig. 1 is embodiments of the invention structure charts

In figure: 1-seals core print, 2-yttrium oxide sand, 3-tracheae, 4-wax-pattern foundry goods, 5-cover plate formwork, 6-oil pipe, 7-formwork, 8-plug.

Detailed description of the invention

Below in conjunction with accompanying drawing, technical scheme of the present invention is described further, but described in required protection domain is not limited to;

5, be illustrated in figure 1 in pipeline and form oil pipe 6, the implementing process of tracheae 3,

(1) tracheae 3 and oil pipe 6 are made into shape as shown in the figure, in tracheae 3 and oil pipe 6 pipeline, fill up 100 order yttrium oxide sands, pipeline opening waterglass aluminum mixture vanadine mud is blocked; Prevent slip from infiltrating in pipeline.

(2) by pipeline somatotype, make with tracheae 3 cavity and foundry goods body main body wax-pattern, make split wax-pattern containing oil pipe 6 cavity and bonding wax-pattern and cover plate wax-pattern 5; Main body wax-pattern is provided with location core print and prevents titanium pipe eccentric under molten metal impulsive force and centrifugal action;

(3) bonding wax-pattern and main body wax-pattern are bonded together, make overall wax-pattern foundry goods 4 with after the roasting of main body wax-pattern steam dewaxing high-temperature vacuum; Split cover plate wax-pattern 5 is made shell separately;

(4) wax-pattern foundry goods 4 is pressed vacuum 9Pa after steam dewaxing; Temperature: 1070 DEG C; Be incubated 4 hours after roasting, be cooled to less than 180 DEG C to come out of the stove with stove;

(5) tracheae 3 made, oil pipe 6 are inserted in roasting shell, at the in-built upper plug head 8 of the pipeline opening exposed, with cover plate formwork 5, pipeline is located, then be combined into integrated poured shell after removing moisture with blowtorch baking;

(6) integrated poured shell is carried out preheating, cast, the foundry goods after cast, walk operation by the technological process of general precision-investment casting.

Claims (3)

1. in titanium investment foundry goods, form a casting technique for complex pipeline, it is characterized in that its processing step is:

(1) pipeline is made into the shape of needs, in pipeline, fills up yttrium oxide sand, pipeline opening waterglass aluminum mixture vanadine mud is blocked;

(2) by pipeline somatotype, and press somatotype making main body wax-pattern, split wax-pattern and cover plate wax-pattern, Split mold comprises bonding wax-pattern;

(3) bonding wax-pattern and main body wax-pattern are bonded together, make overall shell with after the roasting of main body wax-pattern steam dewaxing high-temperature vacuum; Split cover plate wax-pattern is made shell separately;

(4) shell is pressed vacuum≤10Pa after steam dewaxing; Temperature: 1050 ± 20 DEG C; Be incubated 3 ~ 5 hours after roasting, be cooled to less than 180 DEG C to come out of the stove with stove;

(5) pipeline made is inserted in roasting shell, split cover plate wax pattern shell and pipeline are located, then remove moisture with blowtorch baking, be combined into integrated poured shell;

(6) integrated poured shell is carried out preheating, cast, the foundry goods after cast, walk operation by the technological process of general precision-investment casting.

2. a kind of casting technique forming complex pipeline in titanium investment foundry goods according to claim 1, is characterized in that: the yttrium oxide sand in described step (1) is 100 order sand.

3. a kind of casting technique forming complex pipeline in titanium investment foundry goods according to claim 1, it is characterized in that: in described step (2), body die needs to offer location in mind, prevent titanium pipe eccentric under molten metal impulsive force and centrifugal action.