CN101352754A

CN101352754A - EPS investment pattern negative-pressure casting method

Info

Publication number: CN101352754A
Application number: CNA2008101474654A
Authority: CN
Inventors: 刘成文; 杨丽
Original assignee: HOUMA MOFAN MACHINERY MANUFACTURING Co Ltd
Current assignee: HOUMA MOFAN MACHINERY MANUFACTURING Co Ltd
Priority date: 2008-08-19
Filing date: 2008-08-19
Publication date: 2009-01-28

Abstract

The invention relates to a negative pressure casting method of an EPS investment pattern, which comprises the following steps: a. an EPS pattern is chosen, and the pattern surface is coated with a layer of a neat and smooth paint when the pattern density is not less than 26g/L; b. 2-4 layers of a melting pattern paint are coated after the pattern surface is dry; c. the pattern is put into an oven after drying of the pattern surface, the oven temperature is controlled to be 940 DEG C-970 DEG C, and the EPS pattern is burnt away at the time of baking a shuttering; d. the negative pressure is controlled to be 0.06MPa when casting. The negative pressure casting method of the EPS investment pattern solves the problem that big castings can not be cast by investment casting and the maximum casting weight can reach about 3 tons. The EPS melting pattern negative pressure casting method has the advantages of strengthening the negative pressure casting shuttering, improving the surface roughness and precision of the disappearance mould and reducing the coating layers to 2-4 layers, thus reducing the cost.

Description

The EPS investment pattern negative-pressure casting method

Technical field

The invention belongs to lost-foam casting method, be specifically related to a kind of EPS investment pattern negative-pressure casting method.

Background technology

Traditional model casting is to adopt cured mould, loses the cast down of cured back normal pressure.The mould rigidity is poor, and shell easily bursts, and its maximum characteristics are to cast the part that weight generally is not more than 6kg; To be that system shell number is minimum must not be lower than 5 layers for next, will reach 9 layers at most, and the production cycle is long, the cost height.Authentic lost foam casting regurgitates and produces carbon defects when preventing to pour into a mould, require the EPS density of modes the smaller the better, so just brought the yielding defective of mould, if prevent that distortion from strengthening density and not only producing aforementioned two problems, and requirement improves negative pressure and pouring temperature, both increase energy consumption, shortened the life-span of smelting furnace again.The surface roughness of disappearance die casting is also more less better than lost wax casting.

Summary of the invention

The technical problem to be solved in the present invention provides a kind of EPS investment pattern negative-pressure casting method, solves the problem that lost wax casting can not be cast big part, and maximum casting weight can reach about 3 tons, strengthen the negative pressure casting shell, improved disappearance mould surface roughness and precision, coating can reduce to layer 2-4, and cost reduces.

Technical scheme of the present invention: a kind of EPS investment pattern negative-pressure casting method, its step is as follows: a, select for use EPS mould, density to be not less than under the situation of 26g/L, the mould surface hangs and is coated with layer of smooth coating; B, treat that die face is done after, hang again and be coated with layer 2-4 fusible pattern coating; C, etc. after die face does, be put in the baking box, the roasting formwork, oven temperature is controlled at 940 ℃-970 ℃, simultaneously the EPS mould is burnt; When d, cast, negative pressure is controlled at 0.06MPa.

The present invention compared with prior art has following beneficial effect: can cast the big foundry goods about 3 tons.Strengthen the negative pressure casting shell, produce mild steel and can not produce carburetting.The surface roughness and the precision of disappearance die casting have been improved.Can reduce to layer 2-4 with fusible pattern than coating, cost reduces.

The specific embodiment:

A kind of EPS investment pattern negative-pressure casting method, its step is as follows: a, select for use EPS mould, its density to be not less than under the situation of 26g/L, the mould surface hangs and is coated with layer of smooth coating; B, treat that die face is done after, hang again and be coated with layer 2-4 fusible pattern coating; C, etc. die face be put in the baking box after doing, oven temperature is controlled at 940 ℃-970 ℃, in the roasting formwork EPS mould is burnt; When d, cast, negative pressure is controlled at 0.06MPa.

Bright and clean coating is selected the 199th page of " lost foam casting practical technique " book, the 210th page for use, disclosed bright and clean coating, and by Dong Xiuqi, Zhu Lijuan chief editor, China Machine Press publishes.In January, the 2007 front page second impression.

Precoating selects for use " 6 Special Processes of Metal Castings of casting handbook " the 77th～114 page of book open.Can cast branch by the mechanical mechanics of China and compile, in August, 2006 second edition the third printing.

Claims

1, a kind of EPS investment pattern negative-pressure casting method is characterized in that its step is as follows:

A, select the EPS mould for use, mould is not less than in density under the situation of 26g/L, and the mould surface hangs and is coated with layer of smooth coating;

B, treat that die face is done after, hang again and be coated with layer 2-4 fusible pattern coating;

C, etc. die face be put in the baking box after doing, oven temperature is controlled at 940 ℃-970 ℃, in the roasting formwork EPS mould is burnt;

When d, cast, negative pressure is controlled at 0.06MPa.