CN1045555C - Simple casing tech by lost wax casting - Google Patents

Abstract

The present invention relates to a simple making technique for shells by lost wax casting. The technique comprises the following steps: immersing the surface of a wax mould in alcohol-base paints for 2 to 3 times, and drying the surface by cold wind every time; filling self-hardening sand at the back for shaping; immersing the wax mould in water glass for 1 to 8 minutes after hardening, taking out the wax mould for drying in shade and hardening, and then dewaxing the wax mould by hot air; calcining the dewaxed wax mould at 400 to 900 DEG C to obtain a shell. The present invention has the advantages of simplified shell making technique, no sand spreading step, no volatilization of corrosive ammonium chloride in calcination, environmental improvement, easy cleanness of an obtained casting after pouring, no sand adhesion and high production efficiency, and is suitable for the precision casting of ferrous metal and non-ferrous metal whose weight is from a plurality of grams to scores of kilograms.

Description

Easy casing tech by lost wax casting

The present invention relates to casting technique, especially a kind of casing tech by lost wax casting.

In the background technology field, conventional casing tech by lost wax casting complexity, operation is various, spreads silica flour behind its surface layer dip-coating material, in the ammonium chloride solution pond, harden, dry in the shade, be repeatedly twice, go up reinforced layered slurry then, stucco, sclerosis, dry in the shade, 6～8 times repeatedly, not only operation is many, speed slow (the system shell stage is generally taken 3～5 days), the work-yard is big, and ammonium chloride can corrode steel equipment, silica flour flies upward, and influences workers'health, the many more easy more waste products that go out of operation.

The objective of the invention is: be developed into and a kind ofly soak alcohol-base paint on the wax-pattern surface, self-hardening sand molding is filled at the back, behind the steep water glass, the easy casing tech by lost wax casting with hot blast dewaxing, roasting form can solve some problems that exist in the background technology field.

To achieve the above object of the invention, the technical solution used in the present invention is:

1. soak alcohol-base paint 2～3 times on the wax-pattern surface, dry up with cold wind at every turn, self-hardening sand molding is filled at the back, after the sclerosis, steep water glass (M=2.8～3.2) 1～8 minute, taking-up is dried in the shade after the sclerosis, with the dewaxing of 60～120 ℃ of hot blasts, 400～900 ℃ of roasting temperatures 0.5～4 hour;

2. the preparation of self-hardening sand

A. fill a prescription (% by weight)

Standard quartz sand or corundum sand 75/150 order 100

Furane resins 0.2～2

Glycerol triacetate or concentration are 70～75% p-methyl benzenesulfonic acid 0.1～2

B. sand mulling craft

Sand glycerol adding triacetate mixing adds mixed with resin after 20～120 seconds after 1～3 minute again, goes out sand molding; Or sand to add concentration be 70～75% p-methyl benzenesulfonic acid mixing after 1～3 minute, add mixed with resin again after 20～120 seconds, go out sand molding.

The present invention compares with background technology, the useful effect that has is: the foundry goods that it was cast removes dimensional accuracy, surface roughness meets outside the investment pattern precision casting requirement, also have process for making shell and simplify, no stucco operation, non-corrosive ammonium chloride evaporates during roasting, improve environment, the casting cleaning that obtains after the cast is easy, and no scab is boosted productivity.It is applicable to that weight is from several hot investment castings that restrain tens kilograms ferrous metal and non-ferrous metal.

Be embodiments of the invention below:

Embodiment 1

Lion shape wax-pattern (or module) soaks (brush or spray) alcohol-base paint 2～3 times on the surface, dry up with cold wind at every turn, self-hardening sand molding is filled at the back, after the sclerosis, steep water glass (M=2.8～3.2) 1～3 minute, taking-up is dried in the shade after the sclerosis, with 60～80 ℃ of 2 hot blast dewaxing, 500～650 ℃ of roasting temperatures 1 hour, the imitative gold copper of pattern of fever cast knocked out formwork layer of sand and dope layer gently after the cooling, obtain any surface finish of lion shape copper chapter foundry goods, no scab phenomenon, cleaning is very convenient, and every in copper chapter nearly weighs 120 grams.

A. the prescription of self-hardening sand (% by weight)

Standard quartz sand or corundum sand 75/150 order 100

Furane resins 0.5

Glycerol triacetate 0.6

B. sand mulling craft

Sand glycerol adding triacetate mixing adds mixed with resin after 30～60 seconds after 1～3 minute again, goes out sand molding.

Embodiment 2

" flying apsaras " wax-pattern (or module) soaks (brush or spray) alcohol-base paint 2～3 times on the surface, dry up with cold wind at every turn, self-hardening sand molding is filled at the back, after the sclerosis, and steep water glass (M=2.8～3.2) 8 minutes, taking-up is dried in the shade after the sclerosis, with the dewaxing of 80～100 ℃ of hot blasts, 600～800 ℃ of roasting temperatures 2～3 hours, pattern of fever cast 35# molten steel (watering about 1600 ℃ of temperature), remove formwork after the cooling, cast(ing) surface does not have viscosity sand layer.195 millimeters of " flying apsaras " steel-casting diameter of phi, thick about 12 millimeters of edge, every nearly weighs 2.4 kilograms.

A. the prescription of self-hardening sand (% by weight)

Standard quartz sand or corundum sand 75/150 order 100

Furane resins 1.5

P-methyl benzenesulfonic acid (concentration is 70%) 0.8

B. sand mulling craft

Sand added the p-methyl benzenesulfonic acid mixing after 1～3 minute, added mixed with resin again after 30～60 seconds, went out sand molding.

Claims (1)

1. easy casing tech by lost wax casting is characterized in that:

1) soak alcohol-base paint 2～3 times on the wax-pattern surface, dry up with cold wind at every turn, self-hardening sand molding is filled at the back, after the sclerosis, steep water glass (M=2.8～3.2) 1～8 minute, taking-up is dried in the shade after the sclerosis, with the dewaxing of 60～120 ℃ of hot blasts, 400～900 ℃ of roasting temperatures 0.5～4 hour;

2) preparation of self-hardening sand

A. fill a prescription (% by weight)

Standard quartz sand or corundum sand 75/150 order 100

Furane resins 0.2～2

Glycerol triacetate or concentration are 70～75% p-methyl benzenesulfonic acid 0.1～2

B. sand mulling craft

Sand glycerol adding triacetate mixing adds mixed with resin after 20～120 seconds after 1～3 minute again, goes out sand molding; Or sand to add concentration be 70～75% p-methyl benzenesulfonic acid mixing after 1～3 minute, add mixed with resin again after 20～120 seconds, go out sand molding.