CN206169186U - Prevent psammitolite device of thermal fragment in production of steel -casting sand -lined metal mould casting - Google Patents

Abstract

The utility model relates to a prevent psammitolite device of thermal fragment in production of steel -casting sand -lined metal mould casting, it belongs to mechanical. The utility model discloses a swage, cover sand bed, cast steel foundry goods and breakable psammitolite, the swage includes swage and swage down, should go up the swage and match each other with swage down, and it has the sand bed of covering to cover in the swage, has the casting mould die cavity in the swage, and the shaping is cast to the cast steel foundry goods in this casting mould die cavity, and breakable psammitolite setting easily produces the position department of thermal fragment at the cast steel foundry goods. The utility model discloses it is rational in infrastructure, can prevent thermal fragment defect among the cast steel casting production effectively, reduce the foundry goods rejection rate, do benefit to the dimensional stability of foundry goods product, adjust the cooling rate at psammitolite device position effectively.

Description

The core device of hot tearing is prevented in a kind of steel-casting Sand-Faced Metal Mould Casting production

Technical field

This utility model is related to a kind of device, and in producing more particularly, to a kind of steel-casting Sand-Faced Metal Mould Casting hot tearing is prevented Core device, it belongs to mechanical.

Background technology

Sand-Faced Metal Mould Casting belongs to one of Special Processes of Metal Castings, and its casting mold is that a thin layer precoated sand shape is covered with metal mold inner chamber Into casting mold.Sand-Faced Metal Mould Casting production is a kind of energy-conservation, the mode of production of section material, is adopted by many castings production enterprises. Iron Mould Coated Sand is typically mainly used in the production of iron casting, and the surface quality of continuous castings of production is good, and dimensional accuracy is high, inherence tissue and Comprehensive mechanical performance is good, is a kind of economical production mode for producing premium casting.

In order to reduce the cost of Steel Castings, all technical of cast steel foundry goods is improved, progressively carried out steel-casting Sand-Faced Metal Mould Casting production application.Compared with ironcasting Sand-Faced Metal Mould Casting application, the production application of steel-casting is mainly deposited Problem be exactly the foundry production because of steel-casting in, shrinkage is far longer than ironcasting, and cast steel in high temperature When, the bad mechanical property such as intensity, so when steel-casting is produced using Sand-Faced Metal Mould Casting, cast steel foundry goods is particularly easy to produce heat One of phenomenon is split, so as to cause foundry goods to scrap, the reason for this is also current Steel Castings less employing Iron Mould Coated Sand technique.

Publication date is on 04 23rd, 2014, in the Chinese patent of Publication No. 103736937A, discloses a kind of name The referred to as patent of invention of " cracking strip of thin-walled box steel-casting ".The patent integrally casts out anti-in steel-casting matrix two sides junction Split muscle, although the patent eliminates cracking phenomena in thin-walled box steel-casting, but the structure is not particularly suited for steel-casting ferrum Type covers the phenomenon that hot tearing is produced in sand Foundry Production, therefore or can not solve cast steel foundry goods is particularly easy to produce decrepitation.

Utility model content

The purpose of this utility model is to overcome above-mentioned deficiency present in prior art, and provides a kind of structure design and close Reason, can be effectively prevented thermal fragmentation defect in cast steel castings production, casting wasted product rate be reduced, beneficial to the dimensionally stable of cast product Property, prevent the core of hot tearing from filling in the steel-casting Sand-Faced Metal Mould Casting production of the rate of cooling for effectively adjusting core device position Put.

The technical scheme in the invention for solving the above technical problem is：Prevent in the steel-casting Sand-Faced Metal Mould Casting production The only core device of hot tearing, including swage, layer of sand and cast steel foundry goods are covered, the swage includes upper swage and lower swage, ferrum on this Type and lower swage are mutually matched, and layer of sand is covered with swage, there is casting mold die cavity in swage, and cast steel foundry goods is finally in the casting mold die cavity Interior casting, it is characterised in that：Also include frangible core, the frangible core is arranged on the portion that cast steel foundry goods is also easy to produce hot tearing At position；It is rational in infrastructure, thermal fragmentation defect in cast steel castings production can be effectively prevented, casting wasted product rate is reduced, and can effectively adjust The rate of cooling at section core device position.

Preferably, frangible core described in the utility model is double-decker, the centre of frangible core is provided with cellular sky Hole；Under by certain squeezing action power, the cellular empty pore structure is crushed, and is receiving original frangible core size The direction of extruding force reduces or shortens.

Preferably, frangible core described in the utility model is in cast steel foundry goods cooling procedure, in the middle of the frangible core Cellular empty hole brittle fracture under shrinkage stress effect, so that frangible core is formed produce and cast steel foundry goods between at casting mold Raw gap；The hindered contraction for making the original position becomes not hindered contraction, releases foundry goods solid-state cooling procedure linear shrinkage generation Shrinkage stress, it is to avoid cast steel foundry goods produces thermal fragmentation defect at the position.

Preferably, one layer therein of the double-decker of frangible core described in the utility model is required according to foundry goods cooling Can be formed by chill；By the required rate of cooling for adjusting the thickness of chill to adjust the foundry goods position, meet foundry goods and coagulate Gu the requirement of cooling.

This utility model compared with prior art, with advantages below and effect：1st, this is adopted in Iron Mould Coated Sand casting mold Core device is planted, the generation of thermal fragmentation defect in cast steel castings production can be effectively prevented；2nd, by chill in change sand core structure Riding position and chill thickness are obtained to adjust the solidification cooling at the foundry goods position more to be had to casting solidification process The solidification cooling condition of profit, reduces casting wasted product rate；3rd, using frangible core device Iron Mould Coated Sand casting mold swage, it is big generous Foundry goods process medium casting of unpacking out separate with swage；4th, the foundry goods produced using frangible core device casting mold, foundry goods To mitigate, the casting residual stress of foundry goods greatly reduces hindered contraction degree, is conducive to the dimensional stability of cast product.

Description of the drawings

Fig. 1 is the structural representation one that this utility model embodiment is also easy to produce hot tearing position.

Fig. 2 is the structural representation two that this utility model embodiment is also easy to produce hot tearing position.

Fig. 3 is the frangible sand core structure schematic diagram one of this utility model embodiment Iron Mould Coated Sand steel-casting.

Fig. 4 is frangible sand core structure schematic diagram after Fig. 3 attrition crushings.

Fig. 5 is the frangible sand core structure schematic diagram one of this utility model embodiment Iron Mould Coated Sand steel-casting.

Fig. 6 is frangible sand core structure schematic diagram after Fig. 5 attrition crushings.

Fig. 7 is the casting mold structure schematic diagram that this utility model embodiment places frangible core device.

Fig. 8 is the frangible core of this utility model embodiment squeezed broken knot for preventing hot tearing from producing in steel-casting cooling procedure Structure schematic diagram.

In figure：Swage 1, upper swage 11, lower swage 12 covers layer of sand 2, frangible core 3, casting mold die cavity 4, cast steel foundry goods 5, honeybee Nest shape cavity hole 6, be obstructed position A, cools down B at hot tearing of being obstructed, extruding force F.

Specific embodiment

Below in conjunction with the accompanying drawings and by embodiment the utility model is described in further detail, and following examples are right It is of the present utility model explanation and this utility model is not limited to following examples.

Embodiment.

Referring to Fig. 1 to Fig. 8, the swage 1 in the present embodiment includes upper swage 11 and lower swage 12, swage 11 and lower ferrum on this Type 12 is mutually matched, and being covered with swage 1 in layer of sand 2, swage 1 has casting mold die cavity 4, and cast steel foundry goods 5 is arranged on the casting mold die cavity 4 Interior, frangible core 3 is arranged on the position that cast steel foundry goods 5 is also easy to produce hot tearing.

Cellular sky of the frangible core 3 in the present embodiment in the cooling procedure of cast steel foundry goods 5, in the middle of the frangible core 3 The brittle fracture under shrinkage stress effect of hole 6, so that between producing and cast steel foundry goods 5 between at the formation casting mold of frangible core 3 Gap；Frangible core 3 is double-decker, and the centre of frangible core 3 is provided with cellular empty hole 6；The double-decker of frangible core 3 its In one layer according to cast steel foundry goods 5 cooling require also can be formed by chill.

Prevent the process of hot tearing as follows in the production of the present embodiment steel-casting Sand-Faced Metal Mould Casting：

（1）Frangible core 3 is positioned over into the hindered contraction position in the casting mold of Iron Mould Coated Sand cast steel casting；

（2）Pouring molten steel is entered into casting mold die cavity 4, solidification cooling；

（3）In cast steel 5 cooling meat of foundry goods, because of the shrinkage stress that foundry goods linear shrinkage is produced, frangible core 3 is extruded brokenly It is broken, so as to form certain space between foundry goods and casting mold；

（4）Will be because during the generation linear shrinkage of foundry goods solid-state cooling procedure, producing because of casting mold deformability between foundry goods and casting mold Shrinkage stress discharge substantially, it is therefore prevented that cause the phenomenon of casting thermal fragmentation to occur because foundry goods shrinkage stress is excessive.

The crushing strength of the frangible core 3 in the present embodiment should be less than the cooling procedure after completing the setting of cast steel foundry goods 5 In the position produce the stress intensity of fire check.

The present embodiment places frangible molding core at the position that cast steel foundry goods 5 is also easy to produce hot tearing, when cast steel foundry goods 5 is in solidification In cooling procedure after the completion of cooling, with the linear shrinkage of foundry goods, the increase of shrinkage stress, act on frangible molding core Core is squeezed broken by shrinkage stress, most at last linear shrinkage stress discharges completely, it is to avoid the generation of decrepitation.

The frangible core device operation principle of hot tearing is prevented in the production of the present embodiment steel-casting Sand-Faced Metal Mould Casting：Swage covers The casting mold of sand casting is to be covered with a thin layer overlay film on the swage without deformability completely of shaping to form, and casting mold die cavity 4 is thin to be covered It is the swage of perfect rigidity behind layer of sand.Therefore, the casting mold rigidity of Iron Mould Coated Sand is very high, and the deformability of casting mold is very poor.Foundry goods Cast is entered after casting mold, and with being gradually lowered for temperature, molten iron or molten steel carry out cooled and solidified from liquid to solid-state, to be solidified complete Cheng Hou, with the further reduction of temperature, foundry goods proceeds by Solid State Contraction, certain linear shrinkage is produced, until casting temperature Unpacking temperature is reduced to, foundry goods of unpacking out is carried out.Because the rigidity of Iron Mould Coated Sand casting mold is very well, casting mold is in foundry goods cooling procedure Substantially seldom there is deformability, the cooling meat, linear shrinkage so with foundry goods is being hindered by casting mold, and foundry goods will be produced The very big stress that is obstructed, when the stress that is obstructed is more than the calorific intensity at the foundry goods position, the position will crack, that is, custom " hot tearing " for claiming, as Figure 1-Figure 2, is obstructed position A and cooling is obstructed B at hot tearing.

In ordinary sand casting production, the identical foundry goods deformability suitable because sand mold type molds have just is not easy to produce Heat is split.And the high rigidity of Iron Mould Coated Sand casting mold, rare deformability, just it is particularly easy to cause cast steel foundry goods 5 to shrink position of being obstructed Thermal fragmentation defect.

As shown in fig. 7, frangible core 3 is placed at position of being obstructed in casting mold medium casting cooling procedure, solidify after casting pouring When linear shrinkage can produce certain shrinkage stress in cooling procedure afterwards, when the stress for shrinking also less than produces the stress of hot tearing, and More than the structure of frangible core 3 intensity when, frangible core 3 is crushed, and casting mold position of being obstructed just generates certain void space, this Sample foundry goods position of being obstructed can be no longer obstructed with free shrink, and shrinkage stress is just released completely, and so as to eliminate foundry goods heat is produced The condition split, it is ensured that foundry goods is complete, eliminates thermal fragmentation defect.

Frangible core 3 is mainly positioned over the position that casting mold medium casting is also easy to produce thermal fragmentation defect by the present embodiment, works as molten steel Cast is completed into casting mold, solidification cooling, in subsequent solid-state cooling procedure, when the stress that the linear shrinkage of foundry goods is produced is more than During core crushing strength, i.e., the stress that the linear shrinkage of foundry goods is produced should be less than producing the stress of hot tearing, and frangible core 3 is just broken, Certain spatial joint clearance is formed between frangible core 3 and foundry goods, the hindered contraction for making the original position becomes not hindered contraction, The shrinkage stress of foundry goods solid-state cooling procedure linear shrinkage generation is released, foundry goods can be avoided to produce thermal fragmentation defect at the position.

As shown in figures 3 to 6, the structure of frangible core 3 is double-decker in the present embodiment, and centre is cellular empty hole 6, under by certain squeezing action power, the honeycomb texture is crushed, and makes original core size contract in the direction of power F that is squeezed Little or shortening.

Frangible core 3 in the present embodiment is positioned over into the hindered contraction position in the casting mold of Iron Mould Coated Sand cast steel casting, During the cooling meat of cast steel foundry goods 5, because of the shrinkage stress that foundry goods linear shrinkage is produced, can be by the core attrition crushing, so as in casting Certain space is formed between part and casting mold, as shown in figure 8, thus will because foundry goods solid-state cooling procedure produce linear shrinkage when, The shrinkage stress produced because of casting mold deformability between foundry goods and casting mold discharges substantially, it is therefore prevented that because foundry goods shrinkage stress is excessive The phenomenon for causing casting thermal fragmentation occurs.

Additionally, the frangible core 3 in the present embodiment can also be used to adjust casting heat energy-saving position in Sand-Faced Metal Mould Casting technique Rate of cooling.In order to adjust the rate of cooling of core position foundry goods, in core double-decker layer also can be formed by chill, this Sample can adjust the required rate of cooling at the foundry goods position by the thickness of adjustment chill, meet casting solidification cooling Require, make the frangible core 3 in the present embodiment play elimination core rest hot tearing and adjust the position solidification cooling shape The dual function of state.

The quantity of the frangible core 3 in the present embodiment can according to actually being selected, if from multiple frangible cores 3, Multiple frangible cores 3 are both placed in the position that cast steel foundry goods 5 is also easy to produce hot tearing, are effectively prevented heat during cast steel foundry goods 5 is produced Split the generation of defect.

By above-mentioned elaboration, those skilled in the art can implement.

Furthermore, it is necessary to explanation, the specific embodiment described in this specification, is named the shape of its parts and components Claiming etc. can be with difference, and above the content described in this specification is only to this utility model structure example explanation. Equivalence changes or simple change that construction, feature and principle described in all foundation this utility model inventional ideas is done, wrap Include in the protection domain of this utility model patent.This utility model person of ordinary skill in the field can be to described Specific embodiment is made various modifications or supplements or substituted using similar mode, without departing from knot of the present utility model Structure surmounts scope defined in the claims, all should belong to protection domain of the present utility model.

Claims (3)

1. prevent the core device of hot tearing in a kind of production of steel-casting Sand-Faced Metal Mould Casting, including swage, cover layer of sand and cast steel casting Part, the swage includes upper swage and lower swage, and swage and lower swage are mutually matched on this, and layer of sand, swage are covered with swage Inside there are casting mold die cavity, cast steel foundry goods casting in the casting mold die cavity, it is characterised in that：Also include frangible core, it is described easy Broken core is arranged on the position that cast steel foundry goods is also easy to produce hot tearing；The frangible core be double-decker, the centre of frangible core It is provided with cellular empty hole；Cellular cavity of the frangible core in cast steel foundry goods cooling procedure, in the middle of the frangible core Hole is frangible, so that frangible core is formed produce gap and cast steel foundry goods between at casting mold.

2. prevent the core device of hot tearing, its feature from existing in steel-casting Sand-Faced Metal Mould Casting production according to claim 1 In：One layer therein of the double-decker of the frangible core requires to be formed by chill according to the cooling of cast steel foundry goods.

3. prevent the core device of hot tearing, its feature from existing in steel-casting Sand-Faced Metal Mould Casting production according to claim 1 In：The crushing strength of the frangible core produces fire check less than the position in cast steel foundry goods cooling procedure after completing the setting Stress intensity.