CN111408691A

CN111408691A - Sand core structure, pouring system and casting method of high-speed punch base casting

Info

Publication number: CN111408691A
Application number: CN202010189283.4A
Authority: CN
Inventors: 宋贤发; 项铮宇; 吴超; 周宁; 张亚敏; 詹善国
Original assignee: Ningbo Tuotie Machinery Co ltd
Current assignee: Ningbo Tuotie Machinery Co ltd
Priority date: 2020-03-18
Filing date: 2020-03-18
Publication date: 2020-07-14

Abstract

A sand core structure, a pouring system and a casting method of a base casting of a high-speed punch press are characterized in that: the structure comprises a sand core body for filling an oil tank cavity in a base of the high-speed punch press, wherein the sand core body consists of a first sand core and a second sand core, and the first sand core and the second sand core are integrally formed; and a core bone structure is pre-embedded in the connecting part of the first sand core and the second sand core. This application has the location accuracy, fixed firm, is difficult to the fracture under hot-water heating effect and molten iron impact, buoyancy effect, and does not have the advantage of fash yet.

Description

Sand core structure, pouring system and casting method of high-speed punch base casting

Technical Field

The invention relates to the technical field of preparation of high-speed punch base castings, in particular to a sand core structure, a pouring system and a casting method of a high-speed punch base casting.

Background

The high-speed punch has high punching speed, the stroke per minute can reach 1200 times/min, and the production efficiency of the high-speed punch is 5-10 times that of a common punch. The high-speed punching machine rotates by a crankshaft, and then a connecting rod on the crankshaft drives a sliding block to reciprocate downwards to complete punching production, wherein a moving machine part can damage a normal gap due to thermal expansion, or is blocked due to failure of lubricating oil at high temperature, and the mechanical strength of the machine part can be reduced or even damaged due to high temperature. Therefore, in order to ensure the normal operation of the press, the parts operating at high temperature must be cooled.

The base casting of the high-speed punch press is a structure with a cavity inside, wherein the cavity inside is an oil tank for storing lubricating and cooling oil, the temperature of lubricating oil in the oil tank of the base is controlled within plus or minus 0.5 ℃ through adopting double-system oil cooling heating equipment, effective lubrication and cooling are timely provided for each kinematic pair of a transmission system, the temperature of the structure of a mechanical system is balanced, abnormal mechanical wear among the kinematic pairs is reduced, cold and hot deformation of key parts is effectively controlled, influence of the cold and hot deformation on the precision of a machine tool is prevented, the continuity of the machining precision of the high-speed punch press is guaranteed to be constant, the base casting is the base casting structure of the high-speed punch press as shown in figure 1, the blank weight of the casting product is 5800Kg, the pouring weight is 6500Kg, the material is nodular cast iron 500-7A, the external dimension is 2160mm × 1370mm × 870mm, the maximum wall thickness is 420mm, the minimum wall thickness is 30mm, the casting body 1 ' is specifically provided with an oil tank 2 ', a pipeline channel 3 ' is arranged on the side wall of the oil tank, and the oil leakage phenomenon is easily caused by the oil leakage phenomenon, and the oil leakage phenomenon easily occurs at the connection of a second oil tank and the oil leakage hole.

In addition, high-speed punch's base casting structure, in the design casting process, the cavity position that the oil tank formed need set up the psammitolite, the psammitolite belongs to the more common part in the casting field, structure and the size psammitolite location of psammitolite according to actual need are also all the same, in the conventional psammitolite location structure, only need simply become the sand core head in the mould and can use, and just need consider combination psammitolite location accuracy to the psammitolite that some casting moulds formed by the combination of a large number of psammitolites, avoid leading to the inconsistent product of casting mould size to scrap because of the location inaccuracy of psammitolite, different psammitolites can need different location structure: in order to facilitate the manufacture of the sand core, the oil tank sand core in fig. 2 adopts a conventional combination of two sand cores, namely a first sand core 4 'and a second sand core 5', as shown in fig. 2, a flash exists between the first sand core and the second sand core, and the flash is difficult to polish; moreover, because the sand core is large in size, the integral sand core cannot be manufactured, and the integral sand core is difficult to hoist, turn and lower, in addition, the sand core at the pipeline passage in the figures 3-6 can only be divided into a sixth sand core 6 ' and a seventh sand core 7 ', wherein the sixth sand core comprises an A part 6.1 ', a B part 6.2 ' and a middle part 6.3 ' excessively connected with the A part and the B part, and the seventh sand core 7 ' comprises a D part 7.1 ', an E part 7.2 ' and a middle part 7.3 ' excessively connected with the D part and the E part; however, as shown in fig. 3 to 6, since the parts a, B, D and E of the sixth sand core and the seventh sand core are relatively thin, if the positioning and fixing are unstable, the sand cores at the positions of the parts a, B, D and E are easily broken under the high-temperature heat action of molten iron and the impact and buoyancy of the molten iron, thereby causing quality problems. For this reason, it is necessary to design a sand core and a sand core positioning structure having an accurate position and an accurate size.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the sand core structure of the high-speed punch press base, which has the advantages of accurate positioning, stable fixation, difficult fracture under the action of hot metal and high temperature heat, impact of hot metal and buoyancy and no fash.

In order to solve the technical problems, the invention adopts the technical scheme that: a sand core structure of a high-speed punch press base comprises a sand core body used for filling an oil tank cavity in the high-speed punch press base, wherein the sand core body consists of a first sand core and a second sand core, and the first sand core and the second sand core are integrally formed; and a core bone structure is pre-embedded in the connecting part of the first sand core and the second sand core.

By adopting the structure, the core bone of the sand core is pre-embedded in the connecting part of the first sand core and the second sand core, the first sand core and the second sand core are integrated into a complete integrated sand core, and the structure is integrally formed. The rigidity and the strength of the easy-to-break part of the sand core are improved by utilizing the rigidity of the core frame, the integral manufacture of the sand core is realized, and the integral sand core can eliminate the gap between the split sand cores and achieve the aim of no flash.

Preferably, the mandrel structure comprises a first mandrel support, a second mandrel support and a third mandrel support, wherein the first mandrel support is positioned at one end of the second mandrel support and is vertically connected with the second mandrel support; the third core bone bracket is positioned in the middle of the second core bone bracket and is vertically connected with the second core bone bracket; the first core frame support is pre-buried in the first sand core, the second core frame support is pre-buried in the second sand core and extends along the width direction of the second sand core, and the third core frame support is pre-buried in the second sand core and extends along the long side direction of the third sand core close to the first sand core; by adopting the structure, the connection firmness, rigidity and strength of the first sand core and the second sand core can be further enhanced; particularly, the special structure of the position of the base of the high-speed punch press can cause the connection part of the first sand core and the second sand core to be slender and fragile, and the first sand core and the second sand core are easy to break under the action of molten iron pouring or the gravity of the sand cores or the buoyancy of the molten iron; the arrangement and the specific position limitation of the core bone structure can well overcome the defects.

Further preferably, the first mandril support comprises two first longitudinal support rods arranged in parallel and a first transverse support rod vertically connected with the longitudinal support rods; the second core bone bracket comprises two second longitudinal supporting rods arranged in parallel and three second transverse supporting rods vertically connected with the longitudinal supporting rods; the third core bone bracket comprises two third longitudinal supporting rods arranged in parallel and two third transverse supporting rods vertically connected with the longitudinal supporting rods; adopt above-mentioned structure can strengthen the steadiness and the intensity of core bone structure itself, also play fine fastening effect to the psammitolite simultaneously.

Preferably, the longitudinal support rod in the core-bone structure is a reinforcing steel bar with phi 20-phi 25, and the transverse support rod is a reinforcing steel bar with phi 14-phi 16; the rigidity and the strength of the easy-to-break part of the sand core are improved by utilizing the rigidity of the core frame, the integral manufacture of the sand core is realized, the gap between the split sand cores is eliminated, and the aim of no flash is fulfilled.

Preferably, a sixth sand core and a seventh sand core are arranged on the two sides of the first sand core and the second sand core; the sixth sand core is a sand core for filling a second pipeline channel in the base of the high-speed punch press, and the seventh sand core is a sand core for filling a first pipeline channel in the base of the high-speed punch press; the sixth sand core comprises a part A, a part B and a part C in transitional connection with the part A and the part B, wherein the part B is provided with a first extension part which is perpendicular to the part B; the seventh sand core comprises a part D, a part E and a part F in transitional connection with the part D and the part E, wherein the part D and the part E are provided with second extending parts, and the second extending parts are perpendicular to the part B.

Preferably, the outer end parts of the first sand core and the second sand core are respectively provided with a fourth sand core and a fifth sand core, and the fourth sand core and the fifth sand core are respectively provided with a groove matched with the first extension part and the second extension part; by adopting the structure, when the sand core is assembled, the fourth sand core and the fifth sand core are firstly put down, the sixth sand core and the seventh sand core can fall into the fourth sand core and the fifth sand core through the matching and guiding functions of the grooves, and the accurate positioning of the sand cores is ensured through the matching of the concave-convex bayonets; the sixth sand core, the seventh sand core, the fourth sand core and the fifth sand core are reinforced and fixed by filling resin sand, so that the rigidity of the parts of the sand cores which are easy to break is improved, and the problem that the sand cores are easy to break under the action of high-temperature heat of molten iron and the action of impact and buoyancy of the molten iron is solved.

The application also provides a casting system of the high-speed punch press base, which comprises a casting cavity formed by the sand core structure and the molding sand and a pouring system communicated with the casting cavity; the pouring system comprises a sprue, a cross gate and an ingate (ingate); the transverse runners comprise a first long-side transverse runner, a second long-side transverse runner and a short-side transverse runner, and the first long-side transverse runner, the short-side transverse runner and the second long-side transverse runner are communicated in sequence to form a U-shaped transverse runner; the first long-side cross gate and the second long-side cross gate are respectively connected to two ends of the short-side cross gate; the straight pouring channel is vertically connected with the short-side transverse pouring channel; the first long-edge cross gate is communicated with a plurality of ingates on the second long-edge cross gate, one end of each ingate is connected with the long-edge cross gate, and the other end of each ingate extends to the bottom position of the pouring system.

By adopting the pouring system, the materials can be uniformly fed from a plurality of pouring ports to the bottom of the casting cavity, so that the feeding is more stable and uniform; and set up a plurality of ingates moreover, guarantee that the speed and the feeding volume that the molten iron got into the die cavity are even to also can effectively guarantee the steady mould that fills of molten iron, reduce the casting defect.

Preferably, the cross section of the straight pouring channel is circular, the cross section of the horizontal pouring channel is rectangular, and the cross section of the inner pouring gate is circular; the sprue is perpendicular to the plane of the short side of the cross section of the cross runner, and the ingate is also perpendicular to the plane of the short side of the cross section of the cross runner.

Further preferably, a lower runner is further arranged between the runner and the ingate, the cross section of the lower runner is the same as that of the runner, and the surface where the long side of the cross section of the lower runner is located is attached to the runner.

Still further preferably, a filter brick is arranged between the lower cross gate and the cross gate, and the cross section of the filter brick is larger than that of the cross gate. By adopting the structure, impurities and the like in the molten iron can be effectively removed, and the casting defects of the casting are further reduced.

The above-mentioned gating system of this application has satisfied: 1. the casting mold is quickly and stably filled with molten iron in a large flow; 2. the iron liquid in the casting mould is solidified according to the principle of equilibrium; 3. the pouring system has a skimming function; 4. there is a higher pressure head. The pouring system is in a semi-closed type and is provided with a filter, and the system is favorable for quick pouring of molten iron.

Further, the size of each component in the pouring system is as follows: f_{Straight bar}1 ceramic tube with phi 80(mm) inner diameter, F_{Horizontal bar}Length 35 mm, width 55mm, height 90mm, F _{Inner part}10 lines of phi 30 inner diameter porcelain tubes; f_{Straight bar}∶F_{Horizontal bar}∶F_{Inner part}1: 1.58: 1.41. The setting can effectively ensure the stable filling and has less casting defects. The above F represents the cross-sectional area of each corresponding component, and the dimensions of the corresponding components are given above mainly, and the corresponding cross-sectional areas can be directly calculated according to the dimensions, and the specific ratio is defined as the above numerical value according to the rounding principle.

Preferably, the gating system further comprises a plurality of air outlets and risers, wherein the air outlets are arranged on the surface of the casting cavity close to the sprue; the riser is arranged on the surface of the casting cavity close to the sprue and is positioned at the position close to two ends of the casting cavity. By adopting the structure, the quantity of the discharged air is based on the exhaust principle of the casting mold, and the total sectional area of the discharged air is generally larger than that of the inner gate. The air outlet is arranged at the position where scum is most likely to occur or the position where the air outlet is not smooth, so that the slag and gas in the casting mold are favorably discharged out of the cavity, and the flowing direction of the molten iron can be guided and changed; the liquid shrinkage replenishing capacity of the casting is enhanced, 4 rows of necking feeding heads with the diameter of 90mm are arranged at the highest point of the upper plane of the casting, and the height of the necking feeding heads is more than or equal to 400mm, so that the liquid shrinkage replenishing method is beneficial to replenishing the lacking part of the casting due to shrinkage during liquid shrinkage.

Preferably, the cold iron-free casting process has the advantages that the cold iron is used for accelerating the cooling of the hot spot circle of the casting, reducing the hot spot circle at the corner and preventing the defects of shrinkage porosity and shrinkage cavity at the corner. According to the structure of the product, the technology of preparing the alloyed molten iron is combined, and the casting process without the chill is carried out on the casting.

The application also provides a casting method of the high-speed punch base casting, which specifically comprises the following steps:

(1) firstly weighing the following raw materials in percentage by mass: 35-45% of pig iron, 30-35% of scrap steel, 25-30% of foundry returns, and 0.7-1.0% of carburant by total mass of the pig iron, the scrap steel and the foundry returns;

(2) putting all pig iron, scrap steel and foundry returns into a smelting furnace, and then adding a carburant; heating to melt the furnace burden, adding FeSi75-C ferrosilicon (FeSi75-C) and FeMn68C7.0 ferromanganese (FeMn68C7.0 is a national standard high-carbon ferromanganese with the chemical components of 65-72 percent of manganese, 7 percent of carbon and the balance of iron and impurities) after the furnace burden is melted down, wherein the adding amount of the ferrosilicon is 0.50-0.80 percent of the total mass of pig iron, scrap steel and foundry returns, and the adding amount of the ferromanganese is 0.40-0.60 percent of the total mass of the pig iron, scrap steel and foundry returns to obtain a raw iron solution; continuously heating the original iron liquid to 1440-1460 ℃; the components and mass percentage of the obtained original iron liquid are C3.55-3.65%, Si 1.40-1.55%, Mn0.40-0.50%, Sn0.004-0.005%, P is less than or equal to 0.04%, S is less than or equal to 0.025%, and the rest is iron;

(3) spheroidizing by adopting a flushing method, firstly adding a spheroidizing agent into a spheroidizing dam on one side of a spheroidizing bag and compacting, then adding 0.03-0.035% of pure tin and 0.005-0.006% of pure antimony based on the mass of the original iron liquid in the step (2), and finally adding an inoculant with the particle size of 3-8mm and compacting; the molten iron obtained after spheroidizing and inoculation comprises the following components in percentage by mass: 3.40-3.50% of C, 2.35-2.65% of Si, 0.40-0.50% of Mn, 0.030-0.035% of Sn0.0035-0.0045% of Sb0.0035%, not more than 0.04% of P, 0.008-0.012% of S, 0.030-0.045% of Mg, 0.006-0.015% of RE, 4.20-4.40% of CE, and the balance of Fe;

(4) slagging off and standing the molten iron obtained in the step (3), and pouring the molten iron into a casting mold cavity to form a casting when the temperature is reduced to 1280-1300 ℃; carrying out stream inoculation by using inoculation powder while pouring, wherein the addition amount is 0.1-0.12% of the mass of the molten iron; the inoculation powder is a silicon-calcium inoculant and comprises, by mass, 70-75% of Si, 0.8-1.2% of Ca0.8-1.2% of Al, 1.5-2.0% of Ce1.5 and the balance of Fe; after the casting is cooled, obtaining a base casting of the high-speed punch;

preferably, the carburant in the step (1) is a carburant with the elements of, by mass, not less than 98% of C, not more than 0.05% of S, not more than 0.01% of N, not more than 0.3% of ash, not more than 0.3% of volatile matter (volatile matter) and 0.5-3mm of granularity, such as DC series carburant (DC- (1-4) carburant) produced by Dancheng industries (Shanghai) Limited.

Preferably, the nodulizer in the step (3) is a rare earth magnesium alloy: 5.2 to 6.0 percent of Mg, 0.4 to 0.6 percent of RE (rare earth), 44 to 47 percent of Si, 0.8 to 1.2 percent of Ca0, less than or equal to 1.0 percent of Al and the balance of iron, wherein the spheroidization reaction is finished within 120s, and the adding amount of a spheroidizing agent is 1.2 to 1.3 percent of the mass of the original molten iron; the spheroidizing condition improves the absorptivity of magnesium and rare earth, enhances the desulfurization effect, and correspondingly reduces the addition amount of a spheroidizing agent, so that the residual rare earth amount and the residual magnesium amount in molten iron are controlled in a lower range, the residual rare earth amount is controlled to be 0.006-0.012%, and the residual magnesium amount is 0.030-0.040%.

Preferably, the addition amount of the inoculant in the step (3) is 0.5-0.9% of the mass of the original molten iron, the inoculant is a silicon-barium inoculant, the mass percentages of elements of the inoculant are Si 71-73%, Ca 0.7-1.3%, Ba 1.6-2.4%, Al less than or equal to 1.2%, S less than or equal to 0.02%, and the balance is iron.

The large-section nodular cast iron has high heat capacity during casting and slow solidification due to slow cooling speed, and is very easy to cause spheroidization recession and inoculation recession, so that the structure and the matrix of a casting are changed, and the large-section nodular cast iron is particularly serious in the center of the casting. The main manifestations are that graphite nodules are big, the number of graphite nodules is reduced, graphite floats, the graphite nodules are distorted, and various non-spherical graphite is formed, and the graphite mainly has flake shape, worm shape, broken block shape and the like. Meanwhile, due to redistribution of solute elements during solidification, a series of problems such as serious element segregation, intergranular carbides, white cast iron and the like also occur, so that the mechanical property of the nodular cast iron is deteriorated, and particularly the elongation and the plasticity are obviously reduced.

Effect of the principal elements on graphitization

Carbon is an element for promoting graphitization and needs to be reasonably selected according to the size and the wall thickness of the casting. For small ductile iron with thin wall, it is appropriate to increase the carbon equivalent, but increasing the carbon amount or carbon equivalent under the condition of large section can only promote the metamorphosis of graphite.

Silicon plays a very important role in promoting graphitization, and the silicon increases the eutectic temperature, reduces the eutectic carbon content and has great influence on the structure and the performance of the nodular cast iron. Because carbon is enriched in graphite and silicon is mainly distributed in a matrix, silicon does not directly act on the growth of graphite but is enriched at the front edge of the growth of graphite crystals, so that the composition is supercooled. When the content of silicon is too high, the solubility of carbon in molten iron can be reduced, the precipitation of carbon is facilitated, and the free growth of graphite in an enrichment area is promoted to enable the graphite to be distorted.

Manganese is an element for promoting carbide formation and is easy to generate segregation, particularly in a thick and large section, the segregation is very serious, and is enriched on a grain boundary, so that the mechanical property of the thick and large section is reduced and needs to be controlled.

Phosphorus is easy to generate segregation, forms phosphorus eutectic, causes brittleness of castings, and reduces toughness, so that the lower the content of the phosphorus eutectic is, the better the content is.

Sulfur is a counter-spheroidizing element, which not only consumes a spheroidizing agent, causes unstable spheroidization and increases sulfide inclusions, but also needs to be controlled as low as possible. After the sulfur content is low, the addition amount of the nodulizer can be reduced, and the harm caused by residual rare earth brought in the nodulizer is reduced. In the large-section nodular cast iron, molten iron with a certain low sulfur content and good spheroidization does not generate spheroidization recession in the solidification process. And this characteristic is not affected by the solidification rate (cross-sectional dimension).

Magnesium and rare earth both belong to spheroidizing elements. Magnesium is a main spheroidizing element, and the addition amount of magnesium is less and better on the premise of ensuring the spheroidizing quality because white spots appear excessively. The rare earth has the same spheroidization capability as magnesium, and also has the functions of deoxidizing, desulfurizing, degassing, neutralizing spheroidization interference elements such as lead, rare earth, antimony, rare earth and the like, molten iron is purified, graphitization is promoted, and white melting and graphite shape deterioration are caused by excessive residual amount.

Influence of spheroidization and inoculation

The spheroidization is an important process for producing nodular cast iron, which is characterized by adding a proper amount of spheroidizing agent into molten iron to promote the graphite to grow into a spherical shape instead of a flake shape or other shapes, wherein the spheroidizing agent is an important intermediate alloy in the production of the nodular cast iron, and is very important for producing the nodular cast iron with good production performance.

Reasonable inoculation is an important and effective way for increasing the number of graphite spheres, and a small amount of special inoculant is added into the cast iron solution to promote graphitization, prevent the formation of cementite, refine the structure and improve the mechanical property of the material. The multi-stage high-dose inoculation is beneficial to improving the quality of common nodular cast iron, and the large-section nodular iron parts can not eliminate the broken graphite but promote the generation of the broken graphite. The inoculation amount is reduced, the inoculation frequency is reduced, the inoculation time is as short as possible (namely instantaneous inoculation), and the inoculation effect is better.

Drawings

FIG. 1 is a schematic view of a base casting structure of a high speed punch.

Fig. 2 is a schematic view of the combined structure of the first and second sand cores of the prior art (split type).

Fig. 3a sixth sand core configuration schematic (side).

Fig. 4 is a schematic view of a sixth core construction (the other side).

Fig. 5 a seventh sand core configuration schematic (side).

Fig. 6 a seventh sand core configuration schematic (the other side).

Fig. 7 shows a schematic structural view of the integrated molding of the first and second sand cores (sand core ribs embedded).

Fig. 8 shows a schematic view of the construction of the core bone of the sand core of the present application (first angle).

Fig. 9 shows a schematic view of the configuration of the core bone of the sand core of the present application (second angle).

Fig. 10 shows a schematic view of the construction of the core bone of a sand core according to the present application (third angle).

Fig. 11 is a schematic view of a sixth core structure of the present application.

Fig. 12 is a schematic diagram of a seventh sand core configuration of the present application.

Fig. 13 is a schematic view (side view) of the overall core assembly of the present application.

Fig. 14 is a schematic view (another side) of the overall core assembly of the present application.

FIG. 15 is a schematic view of the first, second, sixth, and seventh sand core assembly of the present application.

FIG. 16 is a schematic view of the first, second, fourth and fifth sand core assembly of the present application.

FIG. 17 shows a schematic view (side view) of the combination of the runner system and the cavity structure.

FIG. 18 is a schematic view of the construction of the runner system (first angle).

FIG. 19 shows a schematic view of the gating system (second angle).

FIG. 20 is a partial schematic view of the gating system.

FIG. 21 gold phase diagram of sample of example 1.

FIG. 22 gold phase diagram of sample of example 2.

Detailed Description

The present invention will be described in further detail below with reference to the accompanying drawings, but the present invention is not limited to the following embodiments.

As shown in figures 1, 2 and 7: the sand core structure of the high-speed punch press base comprises a sand core body A used for filling an oil tank cavity 2 ' in the high-speed punch press base, wherein the sand core body is composed of a first sand core 4 ' and a second sand core 5 ', and the first sand core and the second sand core are integrally formed; and a core bone structure a is embedded in the connecting part of the first sand core and the second sand core.

As shown in figures 8-10: the core structure a comprises a first core support 1a, a second core support 2a and a third core support 3a, wherein the first core support is positioned at one end of the second core support and is vertically connected with the second core support; the third core bone bracket is positioned in the middle of the second core bone bracket and is vertically connected with the second core bone bracket; the first core frame support is pre-buried in the first sand core, the second core frame support is pre-buried in the second sand core and extends along the width direction of the second sand core, and the third core frame support is pre-buried in the second sand core and extends along the long side direction of the third sand core close to the first sand core; by adopting the structure, the connection firmness, rigidity and strength of the first sand core and the second sand core can be further enhanced; particularly, the special structure of the position of the base of the high-speed punch press can cause the connection part of the first sand core and the second sand core to be slender and fragile, and the first sand core and the second sand core are easy to break under the action of molten iron pouring or the gravity of the sand cores or the buoyancy of the molten iron; the arrangement and the specific position limitation of the core bone structure can well overcome the defects.

As shown in figures 8-10: the first mandrel support 1a comprises two first longitudinal support rods 11a arranged in parallel and a first transverse support rod 11b vertically connected with the longitudinal support rods; the second core frame bracket 2a comprises two second longitudinal support rods 22a which are arranged in parallel and three second transverse support rods 22b which are vertically connected with the longitudinal support rods; the third core bone bracket 3a comprises two third longitudinal supporting rods 33a arranged in parallel and two third transverse supporting rods 33b vertically connected with the longitudinal supporting rods; adopt above-mentioned structure can strengthen the steadiness and the intensity of core bone structure itself, also play fine fastening effect to the psammitolite simultaneously. In the embodiment, the longitudinal support rod in the core-bone structure is a reinforcing steel bar with phi 20-phi 25(mm), and the transverse support rod is a reinforcing steel bar with phi 14-phi 16 (mm); the rigidity and the strength of the easy-to-break part of the sand core are improved by utilizing the rigidity of the core frame, the integral manufacture of the sand core is realized, the gap between the split sand cores is eliminated, and the aim of no flash is fulfilled.

Specifically, as shown in fig. 7, the first core support 1a of the core structure a extends in the first sand core, and the extending direction of the first longitudinal support rod is consistent with the length extending direction of the first sand core, so that the support and the reinforcing solidification of the sand core can be effectively realized; second core bone support 2a then extends to in the second sand core from first sand core to extend in along the second sand core broadside, third core bone support 3a then extends in along the long limit of second sand core simultaneously, and first core bone support 1a and third core bone support 3a all with second core bone support 2a perpendicular, and extend opposite direction, thereby the structure of the first sand core of better cooperation and second sand core makes first and second sand core integral type structure more firm.

As shown in figures 11-12, 15: a sixth sand core 6 and a seventh sand core 7 are arranged on two sides of the first sand core 4 and the second sand core 5; the sixth sand core is a sand core for filling 3.2 'of the second pipeline channel in the base of the high-speed punch press, and the seventh sand core is a sand core for filling 3.1' of the first pipeline channel in the base of the high-speed punch press; the sixth sand core comprises a part A6.1, a part B6.2 and a part C6.3 in transitional connection with the part A and the part B, wherein the part B is provided with a first extension part 6.4 which is vertical to the part B; the seventh sand core 7 comprises a D part 7.1, an E part 7.2 and an F part 7.3 in transitional connection with the D part and the E part, wherein a second extension part 7.4 is arranged on the D part and the E part and is perpendicular to the B part.

As shown in figures 13-14, 16: the outer end parts of the first sand core 4 and the second sand core 5 (namely the positions of two ends of the two sand cores) are respectively provided with a fourth sand core 8 and a fifth sand core 9, and the fourth sand core 8 and the fifth sand core 9 are respectively provided with a groove 10 matched with the first extension part 6.4 and the second extension part 7.4; by adopting the structure, when the sand core is assembled, the fourth sand core and the fifth sand core are firstly put down, the sixth sand core and the seventh sand core can fall into the fourth sand core and the fifth sand core through the matching and guiding functions of the grooves, and the accurate positioning of the sand cores is ensured through the matching of the concave-convex bayonets; the sixth sand core, the seventh sand core, the fourth sand core and the fifth sand core are reinforced and fixed by filling resin sand, so that the rigidity of the parts of the sand cores which are easy to break is improved, and the problem that the sand cores are easy to break under the action of high-temperature heat of molten iron and the action of impact and buoyancy of the molten iron is solved.

As shown in fig. 17-18, the present application also provides a casting system of a high speed punch press base, which comprises a casting cavity b (since the casting cavity is an intermediate transition cavity for forming a final casting during a casting process, the structure of the cavity is matched with that of the casting, and the positions of the casting cavity can be understood as the positions of the casting) formed by the sand core structure and the molding sand, and a gating system c communicated with the casting cavity; the pouring system comprises a sprue 1c, a cross runner 2c and an ingate 3c (ingate); the transverse runners comprise a first long-side transverse runner 2.1c, a second long-side transverse runner 2.2c and a short-side transverse runner 2.3c, and the first long-side transverse runner, the short-side transverse runner and the second long-side transverse runner are communicated in sequence to form a U-shaped transverse runner; the first long-side cross gate and the second long-side cross gate are respectively connected to two ends of the short-side cross gate; the straight pouring channel is vertically connected with the short-side transverse pouring channel; the first long-edge cross gate is communicated with a plurality of ingates on the second long-edge cross gate, one end of each ingate is connected with the long-edge cross gate, and the other end of each ingate extends to the bottom position of the pouring system.

Specifically, as shown in fig. 18, the ingate 3c is composed of a vertical portion and a vertical portion, wherein the extending direction of the vertical portion is parallel to the extending direction of the sprue, the vertical portion is located at one end of the vertical portion and is communicated with the casting cavity, the length of the vertical portion is far greater than that of the vertical portion, the vertical portion is a short portion, and molten iron is used for rapidly and uniformly entering the casting cavity; in addition, in the embodiment, the number of the sprue is one, the number of the runners is one, the number of the ingates is 10, five runners are uniformly distributed on the first long-edge runner and the second long-edge runner, one of the five runners is located at the left and right positions of the middle part of the long-edge runner, and two of the five runners are distributed at two end parts close to the long edge, so that molten iron can uniformly and smoothly enter the cavity due to the arrangement, and the casting effect is ensured.

As shown in fig. 19, the cross section of the sprue is circular, the cross section of the runner is rectangular, and the cross section of the ingate is circular; the sprue is perpendicular to the plane of the short side of the cross section of the cross runner, and the ingate is also perpendicular to the plane of the short side of the cross section of the cross runner.

As shown in fig. 20, a lower runner 22c is further disposed between the runner and the ingate, the cross section of the lower runner is the same as that of the runner, and the surface of the long side of the cross section of the lower runner is attached to the runner. It is further preferred that a filter block 4c is further provided between the lower runner and the runner, and the cross section of the filter block is larger than that of the runner. By adopting the structure, impurities and the like in the molten iron can be effectively removed, and the casting defects of the casting are further reduced.

Further, the size of each component in the pouring system is as follows: f_{Straight bar}1 ceramic tube with phi 80(mm) inner diameter, F_{Horizontal bar}35/55 height 90(mm), F _{Inner part}10 lines of ceramic tubes with the inner diameter of phi 30 (mm); f_{Straight bar}∶F_{Horizontal bar}∶F_{Inner part}1: 1.58: 1.41. The setting can effectively ensure the stable filling and has less casting defects. The above F represents the cross-sectional area of each corresponding component, and the dimensions of the corresponding components are given above mainly, and the corresponding cross-sectional areas can be directly calculated according to the dimensions, and the specific ratio is defined as the above numerical value according to the rounding principle.

As shown in fig. 17: the pouring system also comprises a plurality of air outlets d and risers e, and the air outlets are arranged on the surface of the casting cavity close to the sprue; the riser is arranged on the surface of the casting cavity close to the sprue and is positioned at the position close to two ends of the casting cavity. By adopting the structure, the quantity of the discharged air is based on the exhaust principle of the casting mold, and the total sectional area of the discharged air is generally larger than that of the inner gate. The air outlet is arranged at the position where scum is most likely to occur or the position where the air outlet is not smooth, so that the slag and gas in the casting mold are favorably discharged out of the cavity, and the flowing direction of the molten iron can be guided and changed; the liquid shrinkage replenishing capacity of the casting is enhanced, 4 rows of necking feeding heads with the diameter of 90mm are arranged at the highest point of the upper plane of the casting, and the height of the necking feeding heads is more than or equal to 400mm, so that the liquid shrinkage replenishing method is beneficial to replenishing the lacking part of the casting due to shrinkage during liquid shrinkage. The gas outlet is a flat structure with a rectangular cross section, the upper part of the dead head is a cylinder, and the lower part of the dead head is a prism which is gradually narrowed, so that molten iron can be well supplemented and gas in the molten iron can be rapidly led out, the metallographic structure is more perfect, and the casting defect is avoided.

The casting process and the casting system belong to a chill-free casting process, and the chill has the effects of accelerating the cooling of the thermal pitch circle of a casting, reducing the thermal pitch circle at the corner and preventing the fillet from generating shrinkage porosity and shrinkage cavity defects. According to the structure of the product, the technology of preparing the alloyed molten iron is combined, and the casting process without the chill is carried out on the casting.

The following is a method for preparing a high-speed punch base casting by using the cavity structure and the gating system, and the corresponding specific embodiment is as follows:

all or most of the castings are placed in the same box as much as possible so as to reduce the size deviation caused by the misshape; the number of types is reduced as much as possible; the part with high quality requirement is placed at the lower part as much as possible, and the process design is based on the scheme of flat casting according to the structural characteristics of the casting, so that arrangement of an inner sprue is facilitated, and the upright post mounting surface is placed at the bottom. Meanwhile, a plurality of inner gates are arranged in the pouring system, so that the number of slag inclusions can be effectively reduced, waste products with slag inclusions can be reduced, and the oil tank is ensured not to leak oil or seep oil; the mechanical property of the casting is improved, the number of inclusions in the metal matrix is reduced, and the service life of the cutting tool can be obviously prolonged.

An inner pouring gate: the design is favorable for weakening the scouring of high-temperature molten iron to a casting mold, preventing the sand washing defect and stopping slag.

And (2) designing a filter at the connecting part of the cross gate and the ingate, wherein the filter adopts a filter brick with the thickness of 100mm × 100mm × 20mm (thickness) of Zhejiang pond refractory and thermal insulation material Limited company.

Straight gate: the sprue is made of a ceramic tube, so that the sand washing defect is greatly reduced, and broken sand is easy to react with impurities in molten iron after entering the cavity, so that a large amount of slag is clamped.

An outer pouring gate: the outer pouring gate is poured by adopting a quantitative ladle plug, has the function of enabling slag and gas to float upwards so as to be beneficial to obtaining a casting with qualified quality, is also beneficial to controlling the pouring temperature, and can be poured at the pouring temperature with good process design.

Gas outlet: the quantity of the discharged gas is based on the exhaust principle of the casting mold, and the total sectional area of the discharged gas is larger than that of the inner gate. The air outlet is arranged at the position where the scum is most likely to occur or the position where the air exhaust is not smooth, so that the slag and the air in the casting mold are favorably discharged out of the cavity, and the flowing direction of the molten iron can be guided and changed.

And (4) riser: the liquid shrinkage replenishing capacity of the casting is enhanced, 4 rows of necking feeding heads with the diameter of 90mm are arranged at the highest point of the upper plane of the casting, and the height of the necking feeding heads is more than or equal to 400mm, so that the liquid shrinkage replenishing method is beneficial to replenishing the lacking part of the casting due to shrinkage during liquid shrinkage.

The large-section nodular cast iron has high heat capacity during casting and slow solidification due to slow cooling speed, and is very easy to cause spheroidization recession and inoculation recession, so that the structure and the matrix of a casting are changed, and the large-section nodular cast iron is particularly serious in the center of the casting. The main manifestations are that graphite nodules are big, the number of graphite nodules is reduced, graphite floats, the graphite nodules are distorted, and various non-spherical graphite is formed, and the graphite mainly has flake shape, worm shape, broken block shape and the like. Meanwhile, due to redistribution of solute elements during self-solidification, a series of problems such as serious element segregation, intergranular carbides, white cast iron and the like can occur, so that the mechanical property of the nodular cast iron is deteriorated, and particularly the elongation and the plasticity are obviously reduced.

Example 1

(1) Weighing the following raw materials in percentage by mass: 38% of pig iron, 35% of scrap steel, 27% of scrap returns, and a carburant: 1.0 percent of the total amount of pig iron, scrap steel and foundry returns;

(2) putting all the pig iron, the scrap steel and the foundry returns weighed in the step (1) into a smelting furnace, and then adding a carburant accounting for 1.0% of the total amount of the formula; heating to melt the furnace burden, adding FeSi75-C ferrosilicon and FeMn68C7.0 ferromanganese after the furnace burden is melted down, wherein the adding amount of the ferrosilicon is 0.70 percent of the total mass of the pig iron, the scrap steel and the scrap returns, the adding amount of the ferromanganese is 0.45 percent of the total mass of the pig iron, the scrap steel and the scrap returns to obtain a raw iron liquid, and continuously heating the raw iron liquid to 1450 ℃; the obtained raw iron liquid comprises, by mass, 3.55% of C, 1.40% of Si, 0.42% of Mn0.0043% of Sn0.030% of P, 0.020% of S, and the balance of Fe;

(3) spheroidizing by adopting a flushing method, firstly adding a spheroidizing agent into a spheroidizing dam on one side of a spheroidizing bag and compacting, then adding 0.03 percent of pure tin and 0.005 percent of pure antimony based on the mass of the original molten iron, and finally adding an inoculant with the particle size of 3-8mm and compacting.

The nodulizer is rare earth magnesium alloy: 5.5 percent of Mg, 0.5 percent of RE, 40 percent of Si, 1.0 percent of Ca1.8 percent of Al0.8 percent of nodulizer, the adding amount of the nodulizer accounts for 1.25 percent of the mass of the original molten iron, and the spheroidizing reaction time is 110 s.

The addition amount of the inoculant is 0.86 percent of the mass of the original molten iron, the inoculant is a silicon-barium inoculant, the mass percentages of the elements are Si 73 percent, Ca1.0 percent, Ba 1.8 percent, Al0.9 percent, S0.009 percent and the balance of iron.

The obtained molten iron comprises, by mass, 3.45% of C, 2.50% of Si, 0.42% of Mn, 0.030% of Sn0.030%, 0.0042% of Sb0.0042%, 0.030% of P, 0.0098% of S, 0.035% of Mg, 0.009% of RE, 4.29% of CE, and the balance of Fe;

(4) and slagging off the molten iron, standing, and pouring the molten iron into the casting mold to form a casting when the temperature is reduced to 1300 ℃. And (3) carrying out stream inoculation by using inoculation powder while pouring, wherein the addition amount is 0.12 percent of the mass of the original iron liquid. And cooling the casting to obtain the nodular cast iron base casting.

The inoculation powder is a silicon-calcium inoculant and comprises, by mass, 73% of Si, 1.0% of Ca, 0.9% of Al, 1.8% of Ce1.8% of Fe, and the balance of Fe.

Physical properties of the cast-on-cast test pieces (70mm × 70mm × 105mm) are shown in tables 1 and 2.

TABLE 1 mechanical Properties of the As-cast test blocks

Item	Tensile strength (MPa)	Yield strength (MPa)	Elongation (%)	Hardness (HB)
					Standard value	≥420	≥290	≥5.0	170～230
Measured value	450	300	8.0	178

TABLE 2 metallographic structure of the cast test block

Item	Nodularity of spheroidization	Size of graphite
			Standard value	≥80％	4～7
Measured value	90	7

The metallographic structure is shown in the attached figure 21: the attached drawings show that the sample prepared by the embodiment of the application has uniform metallographic structure, good spheroidization grade, compact product structure and no oil leakage or oil seepage phenomenon at the oil tank part.

Example 2

(1) Weighing the following raw materials in percentage by mass: 30% of pig iron, 30% of scrap steel, 40% of scrap returns, and a carburant: 0.87 percent of the total amount of pig iron, scrap steel and foundry returns;

(2) putting all pig iron and scrap steel into a smelting furnace, and then adding a carburant accounting for 0.87 percent of the total amount of the formula; heating to melt furnace burden, adding FeSi75-C ferrosilicon and FeMn68C7.0 ferromanganese after the furnace burden is melted down, wherein the adding amount of the ferrosilicon is 0.50 percent of the total mass of pig iron, scrap steel and foundry returns, the adding amount of the ferromanganese is 0.43 percent of the total mass of the pig iron, the scrap steel and the foundry returns, the adding amount of the ferrosilicon is 0.67 percent of the total mass of the pig iron, the scrap steel and the foundry returns to obtain raw iron liquid, and continuously heating the raw iron liquid to 1460 ℃; the obtained raw iron liquid comprises, by mass, 3.55% of C, 1.50% of Si, 0.46% of Mn0.0041% of Sn0.033%, 0.025% of S and the balance of Fe;

(3) spheroidizing by adopting a flushing method, firstly adding a spheroidizing agent into a spheroidizing dam on one side of a spheroidizing bag and compacting, then adding 0.035% of pure tin and 0.005% of pure antimony based on the mass of the original molten iron, and finally adding an inoculant with the particle size of 3-8mm and compacting.

The nodulizer is rare earth magnesium alloy: 5.5 percent of Mg, 0.5 percent of RE, 40 percent of Si, 1.0 percent of Ca1 and 0.8 percent of All. The adding amount of the nodulizer is 1.3 percent, and the spheroidization reaction time is 100 s.

The addition amount of the inoculant is 0.69 percent of the mass of the original molten iron, the inoculant is a silicon-barium inoculant, the mass percentages of the elements are Si 73 percent, Ca1.0 percent, Ba 1.8 percent, Al0.9 percent, S0.009 percent and the balance is iron.

The obtained molten iron comprises, by mass, 3.50% of C, 2.55% of Si, 0.46% of Mn, 0.035% of Sn0.035%, 0.0045% of Sb0.0045%, 0.033% of P, 0.010% of S, 0.037% of Mg, 0.009% of RE, 4.36% of CE, and the balance of Fe;

(4) and slagging off the molten iron, standing, and pouring the molten iron into the casting mold to form a casting when the temperature is reduced to 1290 ℃. And (3) carrying out stream inoculation with inoculation powder while pouring, wherein the addition amount is 0.1%. And cooling the casting to obtain the nodular cast iron base casting.

The physical properties of the cast-on-cast test pieces (70mm × 70mm × 105mm) are shown in tables 3 and 4.

TABLE 3 mechanical Properties of the cast test blocks

Item	Tensile strength (MPa)	Yield strength (MPa)	Elongation (%)	Hardness (HB)
					Standard value	≥420	≥290	≥5.0	170～230
Measured value	455	300	9.0	175

TABLE 4 metallographic structure of the cast test block

Item	Nodularity of spheroidization	Size of graphite
			Standard value	≥80％	4～7
Measured value	95	7

The metallographic structure is shown in the attached figure 22: the attached drawings show that the sample prepared by the embodiment of the application has uniform metallographic structure, good spheroidization grade, compact product structure and no oil leakage or oil seepage phenomenon at the oil tank part.

Claims

1. The utility model provides a psammitolite structure of high speed punch base which characterized in that: the structure comprises a sand core body for filling an oil tank cavity in a base of the high-speed punch press, wherein the sand core body consists of a first sand core and a second sand core, and the first sand core and the second sand core are integrally formed; and a core bone structure is pre-embedded in the connecting part of the first sand core and the second sand core.

2. The sand core structure of the high speed punch press base according to claim 1, wherein: the core structure comprises a first core support, a second core support and a third core support, wherein the first core support is positioned at one end of the second core support and is vertically connected with the second core support; the third core bone bracket is positioned in the middle of the second core bone bracket and is vertically connected with the second core bone bracket; the first core frame support is pre-buried in the first sand core, the second core frame support is pre-buried in the second sand core and extends along the width direction of the second sand core, and the third core frame support is pre-buried in the second sand core and extends along the long side direction of the third sand core close to the first sand core.

3. The sand core structure of the high speed punch press base according to claim 2, wherein: the first mandrel support comprises two first longitudinal supporting rods arranged in parallel and a first transverse supporting rod vertically connected with the longitudinal supporting rods; the second core bone bracket comprises two second longitudinal supporting rods arranged in parallel and three second transverse supporting rods vertically connected with the longitudinal supporting rods; the third core bone bracket comprises two third longitudinal supporting rods arranged in parallel and two third transverse supporting rods vertically connected with the longitudinal supporting rods; the longitudinal support rod in the core structure is a phi 20-phi 25 steel bar, and the transverse support rod is a phi 14-phi 16 steel bar.

4. The sand core structure of the high speed punch press base according to claim 1, wherein: a sixth sand core and a seventh sand core are arranged on the two sides of the first sand core and the second sand core; the sixth sand core is a sand core for filling a second pipeline channel in the base of the high-speed punch press, and the seventh sand core is a sand core for filling a first pipeline channel in the base of the high-speed punch press; the sixth sand core comprises a part A, a part B and a part C in transitional connection with the part A and the part B, wherein the part B is provided with a first extension part which is perpendicular to the part B; the seventh sand core comprises a part D, a part E and a part F in transitional connection with the part D and the part E, wherein the part D and the part E are provided with second extending parts, and the second extending parts are perpendicular to the part B.

5. The sand core structure of the high speed punch press base according to claim 4, wherein: and the outer end parts of the first sand core and the second sand core are respectively provided with a fourth sand core and a fifth sand core, and the fourth sand core and the fifth sand core are respectively provided with a groove matched with the first extension part and the second extension part.

6. The utility model provides a casting system of high speed punch base which characterized in that: the system comprises a casting cavity formed by the sand core structure and the molding sand and a pouring system communicated with the casting cavity; the pouring system comprises a sprue, a cross gate and an inner gate; the transverse runners comprise a first long-side transverse runner, a second long-side transverse runner and a short-side transverse runner, and the first long-side transverse runner, the short-side transverse runner and the second long-side transverse runner are communicated in sequence to form a U-shaped transverse runner; the first long-side cross gate and the second long-side cross gate are respectively connected to two ends of the short-side cross gate; the straight pouring channel is vertically connected with the short-side transverse pouring channel; the first long-edge cross gate is communicated with a plurality of ingates on the second long-edge cross gate, one end of each ingate is connected with the long-edge cross gate, and the other end of each ingate extends to the bottom position of the pouring system.

7. The system of casting a base of a high speed punch press as claimed in claim 6, wherein: the cross section of the straight pouring channel is circular, the cross section of the horizontal pouring channel is rectangular, and the cross section of the inner pouring gate is circular; the sprue is vertical to the surface of the short side of the cross section of the cross runner, and the ingate is also vertical to the surface of the short side of the cross section of the cross runner; and a lower cross gate is also arranged between the cross gate and the inner gate, the cross section of the lower cross gate is the same as that of the cross gate, and the surface of the long edge of the cross section of the lower cross gate is attached to the cross gate.

8. The system of casting a base of a high speed punch press of claim 7, wherein: a filter brick is also arranged between the lower cross pouring channel and the cross pouring channel, and the cross section of the filter brick is larger than that of the cross pouring channel; the size of each component in the pouring system is as follows: f_{Straight bar}1 ceramic tube with phi 80 inner diameter, F_{Horizontal bar}35/55 high 90, F_{Inner part}10 lines of phi 30 inner diameter porcelain tubes; f_{Straight bar}∶F_{Horizontal bar}∶F_{Inner part}＝1∶1.58∶1.41。

9. The system of casting a base of a high speed punch press as claimed in claim 6, wherein: the pouring system also comprises a plurality of air outlets and risers, wherein the air outlets are arranged on the surface of the casting cavity close to the sprue; the riser is arranged on the surface of the casting cavity close to the sprue and is positioned at the position close to two ends of the casting cavity.

10. A casting method of a base casting of a high-speed punch is characterized by comprising the following steps: the method specifically comprises the following steps:

(2) putting all pig iron, scrap steel and foundry returns into a smelting furnace, and then adding a carburant; heating to melt the furnace burden, adding FeSi75-C ferrosilicon and FeMn68C7.0 ferromanganese after the furnace burden is melted down, wherein the adding amount of the ferrosilicon is 0.50-0.80 percent of the total mass of the pig iron, the scrap steel and the foundry returns, and the adding amount of the ferromanganese is 0.40-0.60 percent of the total mass of the pig iron, the scrap steel and the foundry returns to obtain a raw iron liquid; continuously heating the original iron liquid to 1440-1460 ℃; the components and mass percentage of the obtained original iron liquid are C3.55-3.65%, Si 1.40-1.55%, Mn0.40-0.50%, Sn0.004-0.005%, P is less than or equal to 0.04%, S is less than or equal to 0.025%, and the rest is iron;

(3) spheroidizing by adopting a flushing method, firstly adding a spheroidizing agent into a spheroidizing dam on one side of a spheroidizing bag and compacting, then adding pure tin accounting for 0.03-0.035% of the mass of the original molten iron and pure antimony accounting for 0.005-0.006%, and finally adding an inoculant with the particle size of 3-8mm and compacting; the molten iron obtained after spheroidizing and inoculation comprises the following components in percentage by mass: 3.40-3.50% of C, 2.35-2.65% of Si, 0.40-0.50% of Mn0.030-0.035% of Sn0.0035-0.0045% of Sb0.0035%, not more than 0.04% of P, 0.008-0.012% of S, 0.030-0.045% of Mg, 0.006-0.015% of RE, 4.20-4.40% of CE, and the balance of Fe;

(4) slagging off and standing the molten iron obtained in the step (3), and pouring the molten iron into a casting mold cavity to form a casting when the temperature is reduced to 1280-1300 ℃; carrying out stream inoculation by using inoculation powder while pouring, wherein the addition amount is 0.1-0.12% of the mass of the molten iron; the inoculation powder is a silicon-calcium inoculant and comprises, by mass, 70-75% of Si, 0.8-1.2% of Ca0.8-1.2% of Al, 1.5-2.0% of Ce1.5 and the balance of Fe; and cooling the casting to obtain the base casting of the high-speed punch.

11. The method of casting a high speed punch base casting according to claim 10, wherein: the carburant in the step (1) is a carburant with elements of more than or equal to 98% by mass of C, less than or equal to 0.05% by mass of S, less than or equal to 0.01% by mass of N, less than or equal to 0.3% by mass of ash, less than or equal to 0.3% by mass of volatile matter and 0.5-3mm in particle size; the nodulizer in the step (3) is a rare earth magnesium alloy: 5.2 to 6.0 percent of Mg, 0.4 to 0.6 percent of RE, 44 to 47 percent of Si, 0.8 to 1.2 percent of Ca0, less than or equal to 1.0 percent of Al and the balance of iron, wherein the spheroidization reaction is finished within 120s, and the adding amount of a nodulizer is 1.2 to 1.3 percent of the mass of the original molten iron; the addition amount of the inoculant in the step (3) is 0.5-0.9% of the mass of the original molten iron, the inoculant is a silicon-barium inoculant, the mass percentages of the elements are Si 71-73%, Ca 0.7-1.3%, Ba 1.6-2.4%, Al less than or equal to 1.2%, S less than or equal to 0.02%, and the balance is iron.