CN102407285A

CN102407285A - Casting method of stack sand splicing mold

Info

Publication number: CN102407285A
Application number: CN201110367879XA
Authority: CN
Inventors: 倪俭明
Original assignee: NANJING LIUHE JINSHENG MACHINERY FITTINGS FACTORY
Current assignee: NANJING LIUHE JINSHENG MACHINERY FITTINGS FACTORY
Priority date: 2011-11-18
Filing date: 2011-11-18
Publication date: 2012-04-11

Abstract

The invention discloses a casting method of a stack sand splicing mold and belongs to the field of casting. The method comprises: (1) designing castings required to be manufactured, and producing a plurality of intermediate models which are split horizontally; (2) placing the intermediate models into a stack box and pouring sand moldings, opening pouring ports and exhaust ports on the sand molds after drawing, standing for curing, and brushing a layer of charcoal on the surfaces of the sand molds; and (3) stacking the sand molds according to the casting design, aligning the pouring port with the exhaust port, and pouring to prepare the castings. According to the method provided by the invention, because the intermediate molds and stacking sand molds are adopted, the master of accuracy of the castings with complex surfaces is good, and the molding effect of the castings is improved; the surfaces of the castings are more smooth and have high molding degree; and the method can be used for producing large and medium-sized castings, and large processing equipment is not required.

Description

A kind of range upon range of sand mold is pieced together the die cast method

Technical field

The present invention relates to casting field, relate in particular to a kind of range upon range of sand mold and piece together the die cast method.

Background technology

On casting technique, sand casting does not generally receive the restriction of part shape, size and complexity, and raw material sources is wide, instant effect, cost are low, and the foundry goods that adopts sand casting process to produce at present accounts for more than 80% of foundry goods total output.The hand moulding method of sand casting is a lot; Comprise solid pattern molding, the moulding of digging sand, odd-side molding, multiple mould, split case moulding, multiple mould etc.; Multiple mould superposes some sand molds up and down, pours molten iron into from the sprue gate of top, utilizes multiple mould can produce baroque foundry goods; Once-cast also capable of using is accomplished the manufacturing of some foundry goods simultaneously; But the foundry goods levels that this method is produced is different, and lower floor's foundry goods influences casting quality owing to receive the easy case and the sand that rises of rising of the pressure of top.

Along with development of science and technology, the automatic and mechanical degree of Foundry Production is improving constantly, and the direction towards flexible production develops simultaneously, to enlarge the adaptability of in batches different and many variety production.When being proposed more to be strict with, casting factory also need higher cost to keep.For existing middle-size and small-size foundry goods processing factory; Produce very difficulty of bigger foundry goods, and production cost is high, for produce in batches, the production of high accuracy foundry goods all rests on more original level; Even possess the equipment of heavy castings, to the also bad grasp of foundry goods precision.

Summary of the invention

Goal of the invention: the purpose of this invention is to provide a kind of range upon range of sand mold and piece together the die cast method, with finished surface complicated and in, heavy castings, and effectively improve molding effect.

Technical scheme: for realizing above-mentioned purpose, a kind of range upon range of sand mold of the present invention is pieced together the die cast method, comprises the steps:

(1) the foundry goods design that will process, several mid-modules that the level of producing is cut apart;

(2) place folded case to pour into sand molding mid-module, on sand mold, open the sprue gate after the molding with exhaust outlet leaves standstill curing, grey at sand mold surface brush one deck charcoal then;

(3) sand mold is range upon range of according to the foundry goods design, and with sprue gate and exhaust outlet alignment, cast makes foundry goods.

The present invention is cut apart the foundry goods of needs processing through drawing, makes the mid-module that can be combined into a full die.For the ease of producing, the height of said mid-module is consistent, and consistent with folded case height, and the sand mold height of producing like this is consistent, is convenient to produce.

The present invention is through adding resin and the harden(ing)by itself of curing agent realization molding sand in molding sand, when the molding sand color by light yellow when becoming grass green, sand mold possesses enough hardness, can carry out subsequent step.The every 100kg of said molding sand adds the mixture of 2 ~ 4kg furane resins and curing agent, and the volume ratio of said furane resins and curing agent is 2:5 ~ 3:5.The sulfonation curing agent that said curing agent is processed for the phenyl compound sulfonation, said phenyl compound comprises benzene, toluene or xylenes.

When furane resins and curing agent are mixed into molding sand, earlier curing agent was added in the molding sand mixing 1 ~ 2 minute, add furane resins again and mix.

Because the present invention adopts range upon range of sand mold assembled, as suitably not handling, oozes out at joining place easily after the pouring molten iron, influences the product effect, therefore after every layer of sand mold sclerosis,, completely cut off molten iron at sand mold surface brush one deck charcoal ash.

In order to guarantee that molding sand can not be out of shape in cast, the folded case in the said step (2) is the folded case of metal upright around the upper and lower opening, the last lower edge smooth of said folded case.

Beneficial effect: a kind of range upon range of sand mold of the present invention is pieced together the die cast method owing to adopt mid-module and range upon range of sand mold, the foundry goods precision that the surface is complicated is grasped, and improved the molding effect of foundry goods, and cast(ing) surface is more smooth, and forming degree is high.This method can be used in the production, heavy castings, and does not need large-sized processing equipment.

The specific embodiment

A kind of range upon range of sand mold is pieced together the die cast method, several mid-modules that the design of the foundry goods that will process earlier, the level of producing are cut apart, and the height of these mid-modules is identical.

Place folded case to pour into sand molding mid-module, molding sand has added furane resins and curing agent, but the self-hardening moulding.The every 100kg of molding sand adds the mixture of 2 ~ 4kg furane resins and curing agent, and wherein, the volume ratio of furane resins and curing agent is 2:5 ~ 3:5.Curing agent is the special-purpose sulfonation curing agent (model 3#) of casting that Nanjing San Chuan coating Co., Ltd produces, and furane resins are the SCH-300 furane resins that Nanjing San Chuan coating Co., Ltd produces.When furane resins and curing agent are mixed into molding sand, earlier curing agent was added in the molding sand mixing 1 ~ 2 minute, add furane resins again and mix.Molding is then opened the sprue gate on sand mold and exhaust outlet leaves standstill curing.When the molding sand color by light yellow when becoming grass green, sand mold possesses enough hardness, then at sand mold surface brush one deck charcoal ash.

Sand mold after the sclerosis of brushing the charcoal ash is range upon range of according to the foundry goods design, and with sprue gate and exhaust outlet alignment, cast makes foundry goods.

The cast(ing) surface forming degree that utilizes said method to make is very high, has saved follow-up finishing process greatly.

The above only is a preferred implementation of the present invention; Be noted that for those skilled in the art; Under the prerequisite that does not break away from the principle of the invention, can also make some improvement and retouching, these improvement and retouching also should be regarded as protection scope of the present invention.

Claims

1. a range upon range of sand mold is pieced together the die cast method, it is characterized in that this method comprises the steps:

2. a kind of range upon range of sand mold according to claim 1 is pieced together the die cast method, it is characterized in that: the every 100kg of the molding sand in the said step (2) adds the mixture of 2 ~ 4kg furane resins and curing agent, and the volume ratio of said furane resins and curing agent is 2:5 ~ 3:5.

3. a kind of range upon range of sand mold according to claim 2 is pieced together the die cast method, it is characterized in that: earlier curing agent was added in the molding sand mixing 1 ~ 2 minute, add furane resins again and mix.