CN202263919U

CN202263919U - Sand negative-pressure gravity casting mold

Info

Publication number: CN202263919U
Application number: CN2011203599524U
Authority: CN
Inventors: 朱申明
Original assignee: ZHEJIANG WUJING MACHINE MANUFACTURING CO LTD
Current assignee: ZHEJIANG WUJING MACHINE MANUFACTURING CO LTD
Priority date: 2011-09-23
Filing date: 2011-09-23
Publication date: 2012-06-06
Anticipated expiration: 2021-09-23

Abstract

The utility model relates to a casting mold, and provides a sand negative-pressure gravity casting mold. The sand negative-pressure gravity casting mold solves technical problems that an existing sand negative-pressure casting sand box is low in recycling efficiency, a vacuumizing system is complex in structure, and reliability is poor. The sand negative-pressure gravity casting mold is applicable to casting large-size hollow conical rotary castings, is high in sand box recycling efficiency and comprises an upper box and a lower box, wherein the lower box consists of a lower sand box, a vacuum pipe and a bottom cover bucket with a vent, the lower sand box comprises a bottom plate, a vacuum pipe extending hole is disposed in the center of the bottom plate, the bottom cover bucket is reversely fastened on the bottom plate, the vacuum pipe consists of a vertical air inlet pipe and a horizontal communicating pipe, a free end of the horizontal air inlet pipe penetrates through the bottom plate to extend in an air suction cavity consisting of the bottom cover bucket and the bottom plate, an air suction opening is disposed on the wall of the vertical air inlet pipe, and a free end of the horizontal communicating pipe is connected with a vacuumizing system. A sand filtering metal net which is extremely easy to be damaged does not need to be arranged on a vacuumizing pipeline to prevent sand from being sucked into a vacuum pipe to damage the vacuumizing system, and accordingly recycling efficiency of the sand box is quite high.

Description

A kind of sand mold negative pressure gravity casting die

Technical field

The utility model relates to field of metal casting technology, especially relates to a kind of casting mould that is applicable to large-scale hollow taper rotary body foundry goods.

Background technology

Negative pressure casting method is a kind of casting method of inventing and succeeding in developing the beginning of the seventies at the end of the sixties.Existing molding sand negative pressure casting method requires the wall of sandbox to seal, and must be provided with that the grains of sand are crossed device in case the grains of sand get into vavuum pump and damage pumped vacuum systems.Said sand filtration device comprises the wire netting about 110 orders of being located at the bleed-off passage relevant position.These metal Neteases are stopped up or damage by the grains of sand in the use, when sandbox is reused, must clear up or change damaged wire netting.Therefore prior art negative pressure casting method, the repeated use efficient of sandbox is low, and pumped vacuum systems complex structure, dependability are poor, thereby the casting cost is had adverse effect.

Summary of the invention

The utility model mainly is that the sandbox wall that solves existing molding sand negative pressure casting method existence needs hermetically sealed; On the sandbox bleed-off passage filter sand wire netting must be set; And the filter sand wire netting in use is prone to stopped up or damage by the grains of sand; Therefore the repeated use efficient of sandbox is low, and pumped vacuum systems complex structure, dependability difference technical problem provide a kind of and be applicable to what large-scale hollow taper rotary body casting casting was used; The sandbox wall needn't be hermetically sealed, the sand mold negative pressure gravity casting die that the repeated use efficient of sandbox is high.

The used technical scheme of the utility model is: a kind of sand mold negative pressure gravity casting die comprises top box, nowel, ceramic sprue assembly, some riser head heat-preserving covers; Top box comprises sandbox, and nowel comprises sandbox down; Nowel comprises that also vacuum tube and bucket are located at cover bucket at the bottom of the truncated cone-shaped of small end the end; Following sandbox comprise at the bottom of the case support, with support base plate that the upper end is connected and the gusset plate tube that is positioned at the base plate top and is connected at the bottom of the case with base plate; The middle part of base plate is provided with vacuum tube and stretches into the hole; The cover bucket bucket end end, tip upside down on the base plate last, and bucket wall and bucket base fabric are provided with some passages; Vacuum tube comprises two periods in vertical air inlet pipe and level communicating pipe; Vertically the free end of the air inlet pipe vacuum tube that passes the base plate middle part stretches into the hole and stretches in the suction muffler that end cover bucket and plate upper surface by back-off constitute; Vertically the air inlet pipe upper end mouth of pipe is shut; Stretch and on the tube wall in the suction muffler, be provided with the some groups of air entries that circumferentially are uniformly distributed with, the distance of the centre distance plate upper surface of minimum one group of air entry is more than or equal to 30mm, and the free end of level communicating pipe links to each other with pumped vacuum systems; Last sandbox is a round platform tubular sandbox, is laid with some blow vents on its tank wall.

The utility model, last sandbox are round platform tubular top box, and last lower open mouth is laid with passage on the tank wall, so mould sandbox wall is not in and is whole sealing status, and simple in structure, manufacturing cost and use cost is low.The large-scale hollow taper rotary body foundry goods of similar gyratory crusher mantle; Can constitute by several sections round platform cylindrical shells of different taperings; And by covering the suction muffler that bucket and plate upper surface constitute at the bottom of the truncated cone-shaped of back-off; Reduced the consumption of nowel molding sand on the one hand, alleviated nowel weight, the carrying of being convenient to mould is moved; On the other hand; Reduced the flowing velocity of air in suction muffler when bleeding, simultaneously because the vertical air inlet pipe upper end mouth of pipe of vacuum tube is shut, vertically the air entry on the air inlet pipe is opened in the place of stretching on the tube wall in the suction muffler apart from the plate upper surface certain distance.Therefore no matter be at the structure molding sand or when vacuumizing; Even there is the passage of grains of sand cover bucket wall to spill the end of from; Can not fall in the vacuum tube yet or carried by air and be inhaled in the vacuum tube; But directly fall and stay and amass on base plate, stay amass the grains of sand on the base plate can be when making sandbox next time before cover bucket at the bottom of the buckle closure quilt cleaned out.Therefore; The utility model needn't use very easily the filter sand wire netting that damages to prevent that the grains of sand are sucked into into vavuum pump on vacuum-pumping pipeline to cause pumped vacuum systems to damage, therefore also need not be as prior art when sandbox is reused, will expend time in cleaning or replacing filter sand wire netting.So the pumped vacuum systems reliability of the utility model is high, long service life, it is high that sandbox is reused efficient, thereby help improving casting production efficiency, reduces the Foundry Production cost.During Foundry Production, only need to connect vavuum pump in the cast first few minutes and bleed, the gas of suction muffler is constantly walked by suction, and at the inner negative pressure state to be poured that forms of molding sand; During casting, still keep the state of bleeding, therefore casting is carried out under the state of bleeding; Casting cycle molding sand inside keeps negative pressure state always, has improved the flowability of molten metal, and molten steel adsorbs near the die cavity inwall; The minimizing molten steel splashes, turbulent flow; Oxide reduces, and has improved the molten steel degree of purity, reduces foundry goods and forms pore slag inclusion factor; Because of the gas of suction muffler is constantly walked by suction; Ambient atmos gets into from top box and forms convection current, has accelerated the suction muffler air circulation, can effectively prevent to produce the danger of casting gas explosion; Improved the security of Foundry Production, and can form the stratiform of molten steel and solidify trend from the foundry goods inwall to outer wall; Because of negative pressure has increased dies cavity and extraneous pressure differential, make molten metal cooled and solidified under the effect that increases external pressure again, formed foundry goods compact tissue structure, casting compactness improves 2～5%, and the foundry goods mechanical performance is higher than common sand foundry goods 5～10%.

As preferably, cover bucket of the said end superimposedly constitutes by cover bucket down and last cover bucket are separable, and a following barrel end of covering barrel will have the peace bunghole.This preferred version; Be divided into adaptive two branch buckets up and down to end cover bucket; The following cover bucket bucket end, have the peace bunghole; The workman can stand in through the peace bunghole and move down the cover bucket on the base plate of nowel and put operations such as wooden model, chill and solid molding sand during installation, and play cover barrel installing and locating is easy, helps improving nowel manufacturing efficient.

As preferably, ceramic sprue assembly comprises vertical main sprue and is no less than three, the secondary sprue that is communicated with and circumferentially is uniformly distributed with main sprue.This preferred version, the autonomous sprue of molten metal gets into, and flows into the die cavity in the mould simultaneously along the several secondary sprue that circumferentially is uniformly distributed with, and die cavity molten steel distribution consistency degree is high, helps improving casting quality.

As preferably, the diameter of end cover bucket upper vent hole be 2mm to 10mm, the minimum spacing in hole is 100mm.This preferred version, when making nowel, passage is not easy to be stopped up by the grains of sand, and end cover bucket intensity is high, and aeration is good.

As preferably; Vertically the aperture of air inlet pipe is that 30mm is to 80mm; Vertically the tube wall of air inlet pipe is provided with three to five groups of air entries; The air entry number of every group of air entry is three to six, the aperture of air entry be 3mm to 5mm, the distance of the centre distance plate upper surface of minimum one group of air entry is more than or equal to 50mm.This preferred version, vacuum tube vacuumizes effective, and the air entry air velocity is low, and the grains of sand that spill on the base plate and in the passage are difficult for being inhaled in the vacuum tube, and the dependability of pumped vacuum systems is high, and maintenance cost is low, helps reducing the casting cost.

In sum; The beneficial effect of the utility model is: sandbox is simple in structure, and is easy to manufacture, and the molding sand consumption is few; It is high that sandbox is reused the efficient rate; Corresponding pumped vacuum systems is simple in structure, reliability is high, long service life, thereby helps improving casting production efficiency, reduces the Foundry Production cost.

Description of drawings

Fig. 1 is a kind of structural representation of the utility model.

The specific embodiment

Below through embodiment, and combine accompanying drawing, to the utility model technical scheme do into one one bright specifically.

Embodiment is a kind of casting mould of gyratory crusher mantle.

As shown in Figure 1, the utility model casting mould comprises that top box 2,

nowel

1,3, six of ceramic sprue assemblies are symmetrically distributed in the riser head heat-preserving cover 4 of top box 2 upper surfaces; Nowel 1 comprises that down sandbox 1.1, vacuum tube 1.2 and the bucket end are located at cover bucket 1.3 at the bottom of the truncated cone-shaped of small end; Following sandbox 1.1 by support at the bottom of the case 1.1.3, with support the circular bottom plate 1.1.1 that the weldering of 1.1.3 upper end connects together at the bottom of the case and be positioned at the base plate top and constitute with gusset plate tube 1.1.2 that the base plate weldering connects together; Wherein the center of base plate 1.1.1 is provided with vacuum tube and stretches into the hole; At the bottom of 1.3 barrels in the end cover bucket in the last base plate 1.1.1 central authorities that tip upside down on; End cover bucket 1.3 superimposedly constitutes by cover bucket 1.3.1 and last cover bucket 1.3.2 down are separable; The bucket end periphery of following cover bucket 1.3.1 is provided with the location structure that cover bucket 1.3.2 is installed in not shown being used to, and the central authorities at the bucket end of play cover bucket 1.3.1 have the peace bunghole, play cover bucket 1.3.1 and last cover bucket 1.3.2 bucket wall and a barrel end of going up cover barrel 1.3.2 be evenly equipped with passage 1.3.0; The diameter of passage 1.3.0 is 3mm, and the spacing in hole is 100mm; Vacuum tube 1.2 comprises two sections of vertical air inlet pipe 1.2.1 and level communicating pipe 1.2.2; Vertically the free end of the air inlet pipe 1.2.1 vacuum tube that passes base plate 1.1.1 center stretches into the hole and stretches in the suction muffler that is made up of the end cover bucket 1.3 of back-off and base plate 1.1.1 upper surface; Vertically air inlet pipe 1.2.1 and base plate 1.1.1 seal weld connect together; Vertically the air inlet pipe 1.2.1 upper end mouth of pipe is shut, and vertically the aperture of air inlet pipe 1.2.1 is 60mm, and vertically the tube wall of air inlet pipe 1.2.1 is provided with three groups of air entry 1.2.3; The air entry number of every group of air entry 1.2.3 is four; Air entry 1.2.3 is that the aperture is the circular hole of 5mm, and the distance of minimum one group of air entry 1.2.3 centre distance base plate 1.1.1 upper surface equals 50mm, and the free end of level communicating pipe 1.2.2 links to each other with pumped vacuum systems; Top box 2 comprises sandbox 2.1, last sandbox 2.1 be small end at the round platform tubular sandbox last, that upper and lower side is uncovered, be uniformly distributed with the blow vent that some diameters are 10mm on last sandbox 2.1 tank walls, the spacing of passage is 100mm; Six casting incubation risers all are laid in the upper surface of top box 2, and each insulated feeder is provided with an insulating riser sleeve 4; Pottery sprue assembly 3 comprises a vertical main sprue 3.1 and six secondary sprues 3.2 that are communicated with and circumferentially are uniformly distributed with main sprue.Be provided with the alignment pin location structure between last sandbox 1.2 and the following sandbox 1.1.

During manufacturing; At first cope 2.1, weldering be connected with vacuum tube following sandbox 1.1, go up cover bucket 1.3.2 and mfg. moulding die material requested such as cover bucket 1.3.1 and instrument are ready to down; And add five to seven kg of water glass by per hundred kilograms of dried sand and evenly mix and be ready to the molding sand raw material, then:

(1) earlier at the bottom of the cover bucket 1.3.1 bucket down on the last base plate 1.1.1 that tips upside down on sandbox down; The workman stands in the upward mobile cover down of a base plate 1.1.1 bucket 1.3.1 through the following peace bunghole that covers the bucket end central authorities of bucket 1.3.1 and puts in place; Layer overlay thick about 50 arrives the molding sand of 100mm on the surface of the base plate 1.1.1 between the gusset plate tube 1.1.2 of down cover bucket 1.3.1 and play sandbox 1.1 then; Put wooden model assembly 5 to molding sand after solid; Down charging into molding sand and solid between cover bucket 1.3.1 and the wooden model 5 then, during the moulder that stands on the base plate 1.1.1 to put chill 1.4 by technological requirement in good time, treat play to fill up molding sand between cover barrel 1.3.1 and the wooden model 5; Cover folded being anchored to down of last cover bucket 1.3.2 on the bucket 1.3.1 again; And then between last cover bucket 1.3.2 and the wooden model 5, on charge into molding sand and solid on the upper surface at the bottom of the cover bucket 1.3.2 bucket, during and bury in good time and put ceramic sprue assembly 3 well, and then the molding sand in nowel blows carbon dioxide and makes its sclerosis back finishing die joint;

(2) put the contraposition on nowel 1 of last sandbox 2.1 and fix tightly well, between wooden model assembly and last sandbox 2.1, charge into molding sand and solid molding sand; Note having put the riser head heat-preserving cover during this time in good time, blow the molding sand of carbon dioxide hardening top box 2 at last again;

(3) unpack and trip out the wooden model assembly, revise behind the die cavity at the mold cavity surface swabbing oven dry coating.

During casting, before casting, toast die cavity once more and mould assembling is fixed; Be communicated with the free end of the level communicating pipe 1.2.2 of vacuum tube 1.2 with pumped vacuum systems simultaneously; Open vavuum pump in casting about the first five minute and bleed, the casting metals liquid while bleeding waters full molten metal continued and bleeds about five minutes minute, unpacks after the condensation and takes out foundry goods, accomplishes one and takes turns casting manipulations.

Claims

1. a sand mold negative pressure gravity casting die comprises top box (2), nowel (1), ceramic sprue assembly (3), some riser head heat-preserving covers (4); Top box (2) comprises sandbox (2.1), and nowel (1) comprises down sandbox (1.1), it is characterized in that: nowel (1) comprises that also the vacuum tube (1.2) and the bucket end are located at cover barrel (1.3) at the bottom of the truncated cone-shaped of small end; Following sandbox (1.1) comprise support at the bottom of the case (1.1.3), with support base plate (1.1.1) that (1.1.3) upper end is connected and the gusset plate tube (1.1.2) that is positioned at above the base plate and is connected with base plate at the bottom of the case; The middle part of base plate (1.1.1) is provided with vacuum tube and stretches into the hole; End cover bucket (1.3) the bucket end, tip upside down on the base plate (1.1.1) last, and bucket wall and bucket base fabric are provided with some passages (1.3.0); Vacuum tube (1.2) comprises two periods in vertical air inlet pipe (1.2.1) and level communicating pipe (1.2.2); Vertically the free end of air inlet pipe (1.2.1) vacuum tube that passes base plate (1.1.1) middle part stretches into the hole and stretches in the suction muffler by the end cover bucket (1.3) of back-off and base plate (1.1.1) upper surface formation; Vertically air inlet pipe (1.2.1) the upper end mouth of pipe is shut; Stretch and on the tube wall in the suction muffler, be provided with the some groups of air entries that circumferentially are uniformly distributed with (1.2.3), the distance of the centre distance plate upper surface of minimum one group of air entry is more than or equal to 30mm; The free end of level communicating pipe (1.2.2) links to each other with pumped vacuum systems; Last sandbox (2.1) is a round platform tubular sandbox, is laid with some blow vents on its tank wall.

2. a kind of sand mold negative pressure gravity casting die according to claim 1 is characterized in that: said end cover bucket (1.3) is by covering bucket (1.3.1) and last cover bucket (1.3.2) separable superimposed formation down, and barrel end of following cover bucket (1.3.1) has the peace bunghole.

3. a kind of sand mold negative pressure gravity casting die according to claim 1 and 2 is characterized in that: the secondary sprue (3.2) that ceramic sprue assembly (3) comprises vertical main sprue (3.1) and is no less than three, is communicated with main sprue and circumferentially is uniformly distributed with.

4. a kind of sand mold negative pressure gravity casting die according to claim 1 and 2 is characterized in that: the diameter of passage (1.3.0) be 2mm to 10mm, the minimum spacing in hole is 100mm.

5. a kind of sand mold negative pressure gravity casting die according to claim 1 and 2; It is characterized in that: vertically the aperture of air inlet pipe (1.2.1) is 30 to 80mm; Vertically the tube wall of air inlet pipe (1.2.1) is provided with three to five groups of air entries (1.2.3); The air entry number of every group of air entry (1.2.3) is three to six, the aperture of air entry (1.2.3) be 3mm to 5mm, minimum one group of air entry (1.2.3) apart from the distance of base plate (1.1.1) upper surface more than or equal to 50mm.