CN103769552B - Long-life, safe and reliable forging cast iron mold for iron casting machine and manufacturing method thereof - Google Patents

Abstract

The present invention discloses a kind of long-life safety reliable for pig machine and forges pig mold and manufacture method thereof, forging pig mold is by Forging Technology global formation, at least provided with two muscles less than high temperature liquid iron liquid level inside forging pig mold, internal for forging pig mold die cavity is separated at least three shaping mold cavity by muscle, forging pig mold lower end is provided with the overlap joint mouth Q for overlapping mutually with adjacent forging pig mold, forging pig mold upper end arranges the pig mold afterbody P corresponding with adjacent forging pig mold lower end overlap joint mouth, at least provided with two overfalls on overlap joint mouth Q, forging pig mold both sides are provided with molten iron and protect along M1 and M2 and ear T1 and T2 that be connected with carrier bar.Forging molding pig mold avoids as-cast metallographic structure's difference of casting pig mold and various casting flaws, is effectively increased pig mold heat resistive fatigue strength, improves pig mold security reliability, improves pig mold service life.

Description

Long-life, safe and reliable forging cast iron mold for iron casting machine and manufacturing method thereof

technical field

The invention belongs to a casting mold, and in particular relates to a casting mold on a casting machine for casting high-temperature molten iron into pig iron for foundry or pig iron for steelmaking.

Background technique

In the production process of the steel industry, cast iron equipment continuously casts the high-temperature molten iron smelted in the blast furnace into iron blocks (commonly known as bread iron).

At present, its material of the cast iron mold that existing cast iron machine adopts is mostly cast iron or cast steel. The cast iron mold made of cast iron or cast steel is subject to repeated high and low temperature effects during use, and cracks are prone to occur inside the cavity and its ribs, and the cracks will gradually increase, and even cause the cast iron mold to break. Cast iron molds with large cracks must be replaced in time, and the maintenance workload of cast iron machine equipment is very heavy. There are hundreds of cast iron molds on the cast iron machine, and the largest number is more than 1,000. Moreover, after the new cast iron machine is put into production, since cast iron or cast iron molds made of cast iron or cast steel inevitably have casting defects such as porosity and porosity, and the casting metallographic structure level is low, 3~5% of the cast iron molds will be very short in the initial stage of use. Within a short period of time, large cracks or even fractures will occur, which will cause great trouble to the equipment users of cast iron machines, and this problem has also plagued equipment manufacturers for a long time.

On July 13, 2011, the State Intellectual Property Office of China authorized a patent "a cast iron mold for a cast iron machine". This cast iron mold adds rare earth elements to cast steel ZG270-500, which improves the mechanical properties, corrosion resistance and heat resistance of cast steel. However, this cast iron mold is still cast metallographic structure, and there are inevitably casting defects such as pores and looseness. When this cast iron mold is used in batches, it still cannot solve the large cracks or even breakage of the cast iron mold when it is used in the initial stage. technical problems, thus affecting the production efficiency of cast iron machines, and bringing safety hazards.

Contents of the invention

In order to overcome the above-mentioned disadvantages, the present invention changes the production mode of the casting structure cast iron mold manufactured by the casting process that has been adopted for a long time, solves the above-mentioned technical problems existing in the existing cast iron mold in the process of using the cast iron machine, and proposes a cast iron mold for cast iron A long-life, safe and reliable forging cast iron mold for a machine and a manufacturing method thereof.

The new forging cast iron mold manufacturing process reduces the carbon content of the cast iron mold, improves the ductility of the cast iron mold, improves the thermal strain resistance of the cast iron mold, and improves the resistance of the cast iron mold to withstand high temperature molten iron by using high-quality low-carbon rolled steel plates or clad steel plates. The number of thermal shocks can effectively slow down the speed and degree of cracks in the cast iron mold and prolong the service life of the cast iron mold.

The new forging cast iron mold manufacturing process realizes one-time forging of cast iron molds, improves the production efficiency of cast iron molds, and reduces resource consumption by designing forging molds with reasonable structures, formulating reasonable process routes, and selecting reasonable process equipment.

The new forged iron mold manufacturing process can provide long-life, safe and reliable forged iron molds for cast iron machines, which can significantly improve the use effect of cast iron molds, significantly reduce the maintenance and management costs of cast iron molds, and significantly improve the production capacity and production of cast iron machines efficiency.

To achieve the above object, the present invention adopts the following technical solutions:

A long-life, safe and reliable forging cast iron mold for iron casting machines. The forging cast iron mold is integrally formed by a forging process. Inside the forging cast iron mold, there are at least two ribs lower than the liquid level of the high-temperature molten iron. The ribs will make the forging cast iron mold The inner mold cavity is divided into at least three forming mold cavities, the lower end of the forged cast iron mold along the direction of molten iron is provided with a lap joint Q for overlapping with the adjacent forged cast iron mold, and the upper end of the forged cast iron mold along the direction of molten iron is provided with The tail P of the cast iron mold corresponding to the lap spout at the lower end of the adjacent forged cast iron mold along the molten iron direction, at least two overflow ports (K1 and K2) are arranged on the outer edge of the lap spout, and molten iron is arranged on both sides of the forged cast iron mold Guards (M1 and M2) and lugs (T1 and T2) connected to the chain plates.

The above-mentioned long-life, safe and reliable forging cast iron mold for cast iron machine, the thickness b1 of the bottom of the forged cast iron mold is 30-45mm, the thickness b2 of the outer slope is 25-35mm, the thickness b3 of the rib forming is 25-35mm, and the angle of the slope is C 50-70°, the top fillet r1 is 5-15mm, the thickness b4 of the lap joint end is 10-20mm, the inner wall arc R1 of the cross section is 100-130mm, the outer wall arc R2 is 130-175mm, the bottom surface of the longitudinal section be flat or arcuate.

The above-mentioned long-life, safe and reliable forging cast iron mold for cast iron machines, the forged cast iron mold is trapezoidal, that is, L2>L1, the width B3 of the forged cast iron mold is 270-480mm, and the width L3 is 760-960mm, and the forged cast iron mold and the above It overlaps with the lower forged iron mold, the pitch A of the adjacent cast iron mold is 250-450mm, and the lower arc surface of the overlapping mouth (Q) of the upper forged iron mold overlaps with the arc surface of the tail (P) of the lower forged iron mold The gap e1 is 3-6mm, and the lap gap e2 between the lower plane of the lap nozzle (Q) of the upper forged cast iron mold and the upper surface of the tail (P) of the lower forged cast iron mold is 4-8mm.

The above-mentioned long-life, safe and reliable forging cast iron mold for cast iron machine, the inner rib height h1 of the forged cast iron mold is 50-80mm, and the height h2 of the outer groove of the rib is 30-60mm.

The above-mentioned long-life, safe and reliable forging cast iron mold for cast iron machines, the height h3 of the molten iron guards on both sides of the forging cast iron mold is 50-80mm.

The above-mentioned long-life safe and reliable forging cast iron mold for cast iron machine, the material of the forged cast iron mold is high-quality low-carbon structural steel plate or high-temperature resistant alloy steel and high-quality low-carbon structural steel composite steel plate, the thickness of the bottom of the forging cast iron mold is Thickness b1 plus 10-20mm.

The above-mentioned long-life, safe and reliable forging cast iron mold for cast iron machine, the forged cast iron mold uses a special intermediate frequency heating furnace and a heating coil made according to the shape of the blank, the heating time is 5-10 minutes, and the heating temperature is 1100-1350 ℃.

The above-mentioned long-life, safe and reliable forging cast iron mold for iron casting machine, the forging cast iron mold adopts a matching special trimming mold, and the formed forging cast iron mold does not need subsequent manual processing.

The weight of the product cast iron block produced by the present invention is 40-90Kg (connected body), and the weight of a single body after being divided into three, four or six blocks is 6-30Kg.

Adopt above-mentioned technical scheme, the present invention has following advantage:

1. Structure: The forged cast iron mold made by the present invention is formed by forging a whole piece of steel plate, and the ribs inside the mold cavity, lap joints, molten iron guards and connecting ears are formed at one time. The forged cast iron mold avoids the poor metallographic structure and various casting defects of the cast iron mold, effectively improves the thermal fatigue resistance of the cast iron mold, improves the safety and reliability of the cast iron mold, and improves the service life of the cast iron mold. Moreover, the thickness of the forged cast iron mold ribs can be as consistent as possible with the thickness of the bottom and side of the forged cast iron mold. The degree of destruction of thermal stress delays the time for cracks to appear inside the cavity of the cast iron mold or at the position of the ribs, and avoids the potential safety hazard caused by the sudden fracture of the cast iron mold.

2. Material: the forged cast iron mold made by the present invention is made of high-quality low-carbon structural steel rolled steel plate forged cast iron mold. The metallographic structure of the forged cast iron mold is uniform, the grains are fine, and the metallographic structure can reach more than 3 grades. Moreover, the rolled steel plate of high-quality low-carbon structural steel has lower carbon content than the commonly used cast steel, and the elongation δ≥25%. Compared with cast iron molds for steel castings, the internal structure consistency is better and there are almost zero defects. The forged cast iron mold effectively improves the thermal fatigue strength of the cast iron mold, improves the safety and reliability of the cast iron mold, and improves the service life of the cast iron mold. The forged cast iron mold can also be forged from heat-resistant alloy steel and a whole piece of high-quality low-carbon structural steel plate to further improve the heat-resistant fatigue strength and safety reliability of the cast iron mold, and increase the service life. Forged cast iron molds have a long service life and are cost-effective.

3. Dimensional accuracy: the forged cast iron mold made by the present invention adopts a special forging mold forming process, which has high dimensional accuracy and good interchangeability. The connecting bolt holes of the ear parts of the forged cast iron mold can be drilled by a drilling machine or formed by forging, which further reduces the manufacturing cost and improves the applicability of the forged cast iron mold. It can be used together with cast iron molds with similar overlapping dimensions, has good interchangeability and versatility, and broadens the application range of forged cast iron molds.

Description of drawings

Fig. 1 is the plan view of forging cast iron mold of the present invention.

FIG. 2 is a centerline longitudinal cross-sectional view of FIG. 1 .

FIG. 3 is a centerline transverse cross-sectional view of FIG. 2 .

Fig. 4 is a cross-sectional view of the upper and lower overlap of the forging cast iron mold.

detailed description

As shown in Fig. 1, Fig. 2, Fig. 3 and Fig. 4, a long-life, safe and reliable forging cast iron mold for cast iron machines is shown. The forging cast iron mold is integrally formed by the forging process, and at least two low The ribs J1 and J2 on the liquid surface of the high-temperature molten iron separate the internal cavity of the forged cast iron mold into at least three molding cavities N1, N2, and N3. Move F, the lower end of the forging cast iron mold along the direction of molten iron is provided with a splice nozzle Q, at least two overflow ports K1 and K2 are arranged on the outer edge of the splice spout, and molten iron guards M1 and M2 are arranged on both sides of the forge cast iron mold And the ears T1 and T2 connected with the chain plate. The height h3 of molten iron guards on both sides of the forged cast iron mold is 50-80mm. During the working process of the cast iron machine, the high-temperature molten iron flows into the cast iron mold through the molten iron chute. When the upper cast iron mold is filled, it continuously flows into the next cast iron mold through the overflow port above the lap joint. The molten iron is cooled to form large iron blocks in the mold cavity, and the ribs inside the cast iron mold separate the large iron blocks into small iron blocks, commonly known as bread iron.

The thickness b1 of the bottom of the forged cast iron mold of the present invention is 30-45mm, the thickness b2 of the outer slope is 25-35mm, the thickness b3 of the ribs is 25-35mm, the angle C of the slope is 50-70°, and the top fillet r1 is 5-15mm. The thickness b4 at the end of the lap spout is 10-20mm, the arc R1 of the inner wall of the cross section is 100-130mm, the arc R2 of the outer wall is 130-175mm, and the bottom surface of the longitudinal section is a plane or an arc surface. The thickness of the bottom of the cast iron mold, the thickness of the outer slope and the thickness of the ribs are uniform. where cracks appear. The forged cast iron mold solves the problem of uneven wall thickness, and effectively utilizes the advantages of steel plate forging, which greatly reduces the chance of cracking or even breaking the bottom of the cast iron mold and ribs, and improves the safety, reliability and service life of the cast iron mold .

The forged cast iron mold of the present invention is trapezoidal, that is, the lower end and the upper end of the forged cast iron mold along the molten iron direction are parallel to each other, the lower end L1 of the forged cast iron mold along the molten iron direction is smaller than the width L2 of the upper end of the forged cast iron mold along the molten iron direction, and the forged cast iron mold The width B3 is 270-480mm, and the width L3 is 760-960mm. The forged cast iron mold is overlapped with the forged cast iron mold above and below it. The pitch A of the adjacent cast iron molds is 250-450mm. The overlapping mouth of the forged cast iron mold above is (Q) The lap gap e1 between the lower arc surface and the arc surface of the lower forged cast iron mold tail (P) is 3-6mm, and the lap joint (Q) lower plane of the upper forged cast iron mold overlaps with the lower forged cast iron mold tail (P) Joint gap e2 is 4-8mm.

The internal rib height h1 of the forging cast iron mold of the present invention is 50-80mm, and the height h2 of the outer groove of the rib is 30-60mm. The number of ribs is generally 2, 3 or 5, and 3, 4 or 6 small mold cavities are formed inside the cast iron mold. It is also possible to add 1 longitudinal rib to form smaller 6, 8 or 12 small mold cavities inside the cast iron mold. It is also possible to combine two cast iron molds to form one large conjoined cast iron mold.

The above-mentioned long-life safe and reliable forging cast iron mold for cast iron machine, the material of the forged cast iron mold is high-quality low-carbon structural steel plate or high-temperature resistant alloy steel and high-quality low-carbon structural steel composite steel plate, the thickness of the bottom of the forging cast iron mold is Thickness b1 plus 10-20mm.

The above-mentioned long-life, safe and reliable forging cast iron mold for cast iron machine, the forged cast iron mold adopts a special intermediate frequency heating furnace and a heating coil made according to the shape of the blank, the heating time is 5-15 minutes, and the heating temperature is 1100-1300 ℃.

The above-mentioned long-life, safe and reliable forging cast iron mold for iron casting machine adopts matching trimming molds, and the formed forging cast iron mold does not need subsequent manual processing.

The above-mentioned long-life safe and reliable forging cast iron mold for cast iron machines, the process route of the forged cast iron mold is:

Steel plate material inspection-->steel plate blanking-->blank heating-->die forging forming-->finished product trimming-->appearance cleaning-->finished product inspection.

The shape of the blanking steel plate and the thickness of the steel plate change with the shape of the forging cast iron mold, which directly affects the steel utilization rate and the production cost of the forging cast iron mold. The heating temperature and heating time of the blank blank are also the key processes that affect the production cost of the forged cast iron mold, and affect the manufacturing quality of the forged cast iron mold.

The weight of the product cast iron block produced by the present invention is 40-90Kg (connected body), and the weight of a single body after being divided into three, four or six blocks is 6-30Kg. The size of the iron block is determined according to the customer's production process requirements. Different sizes, different numbers of blocks and different shapes of cast iron blocks (bread iron) require different forging molds.

Example 1:

The forged cast iron mold is integrally formed by the forging process. There are two partition ribs (J1 and J2) inside the forged cast iron mold. The partition ribs divide the internal cavity of the forged cast iron mold into three molding cavities (N1, N2, N3). The forged cast iron mold is installed on the cast iron machine to overlap each other, and moves from bottom to top (F). The lower end of the forged cast iron mold along the direction of molten iron is provided with a lap joint (Q), and two overflows are provided on the outer edge of the lap joint. Mouth (K1 and K2), the two sides of the forged cast iron mold are provided with molten iron guards (M1 and M2) and ears (T1 and T2) connected with the chain plate. The thickness b1 of the bottom of the forged cast iron mold is 40mm, the thickness b2 of the outer slope is 35mm, the thickness b3 of the rib forming is 35mm, the angle C of the slope is 55°, the top fillet r1 is 12mm, and the thickness b4 of the lap joint end is 15mm. The inner wall arc R1 is 120mm, the outer wall arc R2 is 160mm, and the bottom surface of the longitudinal section is a plane. The forged cast iron mold is trapezoidal, that is, L2 is 670mm, L1 is 590mm, the forged cast iron mold width B3 is 350mm, and the width L3 is 790mm. A is 310mm, the overlapping gap e1 between the lower arc surface of the lap joint (Q) of the upper forged cast iron mold and the arc surface of the tail (P) of the lower forged cast iron mold is 5mm, the lower plane of the lap joint (Q) of the upper forged cast iron mold and The lap gap e2 above the tail (P) of the lower forged cast iron mold is 7mm. The internal rib height h1 of the forged cast iron mold is 70mm, and the outer groove height h2 of the rib is 50mm. The height h3 of molten iron guards on both sides of the forged cast iron mold is 60 mm. The weight of the product cast iron block produced by the present invention is 45Kg (connected body), and the single body weight after being separated into three pieces is 15Kg.

Example 2:

The material of the forged cast iron mold is high-quality low-carbon structural steel plate Q235 with a thickness of 60mm. The forged cast iron mold adopts a special intermediate frequency heating furnace and a heating coil made according to the shape of the blank. The heating time is 9 minutes and the heating temperature is 1200 ℃, the forged cast iron mold adopts a matching special trimming mold, and the formed forged cast iron mold does not need subsequent manual processing.

Example 3:

The forged cast iron mold is integrally formed by the forging process. There are three ribs inside the forged cast iron mold. The ribs divide the inner mold cavity of the forged cast iron mold into four molding cavities. The forged cast iron mold is installed on the cast iron machine to overlap each other. While moving upward (F), the lower end of the forged cast iron mold along the direction of the molten iron is provided with a splice nozzle (Q). and M2) and the ears (T1 and T2) connected with the chain plate, there are 4 connecting bolt holes. The thickness b1 of the bottom of the forged cast iron mold is 45mm, the thickness b2 of the outer bevel is 38mm, the thickness b3 of the rib forming is 40mm, the angle C of the bevel is 65°, the top fillet r1 is 15mm, and the thickness b4 of the lap joint end is 20mm. The inner wall arc R1 is 130mm, the outer wall arc R2 is 175mm, and the bottom surface of the longitudinal section is an arc surface. The forged cast iron mold is trapezoidal, that is, L2 is 830mm, L1 is 720mm, the forged cast iron mold width B3 is 380mm, and the width L3 is 960mm. A is 330mm, the overlapping gap e1 between the lower arc surface of the lap joint (Q) of the upper forged cast iron mold and the arc surface of the tail (P) of the lower forged cast iron mold is 7mm, and the lower plane of the lap joint (Q) of the upper forged cast iron mold is The lap gap e2 above the tail (P) of the lower forged cast iron mold is 9mm. The internal rib height h1 of the forged cast iron mold is 90mm, and the outer groove height h2 of the rib is 70mm. The height h3 of molten iron guards on both sides of the forged cast iron mold is 80 mm. The weight of the product cast iron block produced by the present invention is 80Kg (joint body), and the single weight after being divided into four pieces is 20Kg.

Example 4:

The material of the forged cast iron mold is a composite steel plate of high-quality low-carbon structural steel plate Q235 and stainless steel 1Cr18Ni9Ti, and the thickness is 60mm and 5mm respectively. The time is 12 minutes, and the heating temperature is 1300°C. The forged cast iron mold adopts a matching special trimming mold, and the formed forged cast iron mold does not require subsequent manual processing.

What is disclosed above is only a preferred embodiment of the present invention, and of course it cannot limit the scope of rights of the present invention. Therefore, equivalent changes or equivalent substitutions or obvious deformations made according to the patent scope of the present invention still belong to the present invention. scope of protection.

Claims (6)

1. null1. the long-life safety reliable forging pig mold for pig machine，It is characterized in that: forging pig mold is by Forging Technology global formation，At least provided with two muscles less than high temperature liquid iron liquid level inside forging pig mold，Internal for forging pig mold die cavity is separated at least three shaping mold cavity by muscle，Forging pig mold is provided with the overlap joint mouth Q for overlapping mutually with adjacent forging pig mold along the lower end in molten iron direction，Forging pig mold is arranged along the upper end in molten iron direction with adjacent forging pig mold along the lower end overlap joint corresponding pig mold afterbody P of mouth in molten iron direction，At least provided with two overfalls on overlap joint mouth Q，Forging pig mold both sides are provided with molten iron and protect along M1 and M2 and ear T1 and T2 that be connected with carrier bar，Forging pig mold is trapezoidal，Forging pig mold is parallel along the upper end in molten iron direction with forging pig mold along the lower end overlap joint mouth in molten iron direction，And forge the pig mold width L1 along the lower end overlap joint mouth in molten iron direction less than forging the pig mold width L2 along the upper end in molten iron direction；The material of described forging pig mold is high-quality low carbon-structural steel steel plate or is high-temperature alloy steel and high-quality low carbon-structural steel clad steel plate, and thickness adds 10-20mm for forging pig mold bottom thickness b1.
2. Long-life safety reliable for pig machine the most according to claim 1 forges pig mold, it is characterized in that: described forging pig mold bottom thickness b1 is 30-45mm, outside ramp thickness b2 is 25-35mm, muscle molding thickness b3 is 25-35mm, and bevel angle C is 50-70 °, and top fillet r1 is 5-15mm, overlap joint mouth end thickness b4 is 10-20mm, cross section inwall circular arc R 1 is 100-130mm, and outer wall circular arc R 2 is 130-175mm, and bottom surface, longitudinal section is plane or arc surface.
3. Long-life safety reliable for pig machine the most according to claim 1 forges pig mold, it is characterized in that: described forging pig mold is 270-480mm along distance B3 between the lower end and upper end in molten iron direction, width L3 between two ears is 760-960mm, forging pig mold with its above and below forging pig mold mutually overlap, pitch A of adjacent pig mold is 250-450mm, the overlap joint mouth Q lower camber side of top forging pig mold is 3-6mm with lower section forging pig mold afterbody P cambered surface overlap joint gap e1, the overlap joint mouth Q lower plane of top forging pig mold and lower section are forged and overlapped gap e2 above pig mold afterbody P is 4-8mm.
4. Long-life safety reliable for pig machine the most according to claim 1 forges pig mold, it is characterised in that: the internal muscle height h1 of described forging pig mold is 50-80mm, and muscle exterior groove height h2 is 30-60mm.
5. Long-life safety reliable for pig machine the most according to claim 1 forges pig mold, it is characterised in that: it is 50-80mm that described forging pig mold both sides molten iron protects along height h3.
6. Long-life safety reliable for pig machine the most according to claim 1 forges the manufacture method of pig mold: the process route of described forging pig mold is: steel plate materials inspection--> steel plate cutting--> blank heating--> mould forges the cleaning of molding--> finished product trimming--> outward appearance--> product inspection, described forging pig mold have employed Special middle frequency heating furnace and the heating coil made according to blanking shape, heat time heating time is 5-15 minute, and heating-up temperature is 1100-1300 DEG C.