A casting mold and casting method for ball panel casting

Abstract

The present invention discloses a casting mold and a casting method for a ball panel casting. The casting mold comprises: an upper mold and an upper template and a lower mold and a lower template, wherein a casting cavity is arranged on the surface of the upper template; a plate body is arranged on the surface of the lower template; the casting method comprises the following steps: 1) preparing materials required for each process, including equipment, raw materials required for production and auxiliary materials, etc.; 2) designing a process and performing simulation; 3) making a template wood sample; 4) resin sand molding and box assembly to form a cavity structure; 5) smelting and casting; 6) annealing and cleaning; 7) heat treatment processing; the present invention has the following beneficial effects: solving the problems of casting defects and difficulty in forming ribs of ball panels in the production process, being suitable for the production of small batches of ball panels with the same structure and higher intrinsic quality requirements, and the preparation method has high yield rate, fast production efficiency, convenient operation and is suitable for promotion.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical equipment manufacturing, and in particular to a spherical panel casting casting mold and a casting method. Background Art

[0002] This type of ball panel casting, also known as radiation-proof ball panel, is a ZG40CrNi2Mo alloy steel casting designed and manufactured by China Railway Construction Heavy Industry. This type of casting can be divided into three parts, namely the solid hemispherical structure at the bottom, the flat plate structure in the middle, and the vertical plate structure at the top. From the perspective of casting, although this type of casting has a simple appearance, the method design and actual operation are somewhat difficult. Affected by the material and structure of the casting, it is not only difficult in structural molding, but also has certain difficulties in welding repair, heat treatment and mechanical processing.

[0003] At present, there are not many manufacturers in the country that can produce castings of this type, and they cannot produce stably, with a high scrap rate. The chemical composition and mechanical properties are also difficult to meet the design and installation requirements of the drawings. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the background technology and to provide a casting mold and a casting method for a spherical panel casting which are easy to implement and can be stably produced.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A casting mold for a spherical panel casting comprises an upper mold and an upper mold plate and a lower mold and a lower mold plate. A casting cavity is arranged on the surface of the upper mold plate, the casting cavity is composed of a plurality of hexagonal cavities, an entgate is arranged on one side of the casting cavity, a riser is arranged on the surface of the upper mold plate, an air eye is arranged on a hexagonal cavity vertical plate on the surface of the upper mold plate away from the entgate, and a straight runner is arranged on the surface of the upper mold plate; a plate body is arranged on the surface of the lower mold plate, a spherical protrusion is arranged on the surface of the plate body, a vertical plate is arranged on one side of the plate body, a horizontal runner is arranged on the other side of the plate body, and an entgate is arranged between the horizontal runner and the plate body.

[0007] A lifting handle and a testing block are arranged on one side of the vertical plate.

[0008] A chill is placed in the hexagonal cavity.

[0009] The specification of the riser is φ180*500.

[0010] The material of the cold iron is Q235.

[0011] There are seventeen risers, three of which are connected to the ingrowth; the remaining risers are in the hexagonal cavity, and riser pads are arranged below.

[0012] The riser specification is φ180*500 and the thickness is 25mm.

[0013] The material of the cold iron is Q235.

[0014] A casting method for a spherical panel casting comprises the following steps:

[0015] ⑴ Making mold

[0016] According to the size requirements of the drawing, a set of ball panel casting molds are made in scale;

[0017] ⑵ Cavity production

[0018] Put quartz sand, furan resin and curing agent into sand molding. When the strength of the sand mold reaches the requirement after reaction, the mold can be removed and the box can be turned over. The mold cavity is repaired, sanded and polished. Then the inner wall of the sand mold cavity is painted. After the painting is completed, the paint is ignited. After the burning is completed, the cavity is repaired and the box can be closed.

[0019] ⑶Steel smelting

[0020] The scrap steel is mixed with other furnace materials and smelted in an electric arc furnace to obtain molten steel through oxidation-reduction reaction;

[0021] ⑷ Molten steel casting

[0022] Before pouring the molten steel into the ladle, aluminum ingots and fluorite are added to the ladle in sequence. After the molten steel is turned into the ladle, argon gas is introduced to purify the molten steel. When the argon is blown until the molten steel reaches a certain temperature, the processed molten steel can be obtained.

[0023] ⑸ Casting cleaning

[0024] The molten steel after treatment is hoisted to the casting area, the casting temperature and casting time are controlled, and then it is injected into the cavity through the casting inlet. After the casting is completed, it is kept warm for 36-42 hours under natural conditions; then the cavity is opened, the casting is hoisted out by a crane, and then a complete annealing treatment is performed. After the casting is cooled to a certain temperature with the furnace, it is air-cooled. When the temperature of the casting is completely reduced to room temperature, the riser is hammered and cleaned with an air hammer, and then the uneven parts of the riser pad at the root of the riser are cut flat with a gas cutting gun. Finally, the required ball panel product can be obtained through grinding, cleaning, finishing, sandblasting, quenching, processing, flaw detection and other processes.

[0025] In the step (2), the ratio of quartz sand, furan resin and curing agent is 100:0.9-1.3:0.5-0.7.

[0026] In the step (2), the material of the riser is made of lost foam, the slope of the riser is 1:20, the height of the riser is 500 mm, the outer wall of the riser is wrapped with transparent tape, and the upper and lower surfaces are padded with 15 mm thick wooden boards for easy demoulding.

[0027] The cavity in step (2) needs to be nailed with an iron nail with a diameter of 8 mm and a length of 200 mm at the boss position before closing the box. The iron nail is required to have a smooth surface and be free of rust, oil and coating.

[0028] The cavity in step (2) needs to raise one side of the runner by 500 mm, and pour the sand mold onto the raised sand bed in preparation for pouring.

[0029] The molten steel smelting method in step (3) is to use an electric arc furnace to mix scrap steel, recycled materials and carbon-matching pig iron in a certain proportion, and after power is supplied for melting, add smelting auxiliary materials such as carbon powder, limestone, alloy material, fluorite, etc., remove the slag, analyze the chemical composition of the molten steel, and when the chemical composition of the molten steel meets the requirements of ZG40CrNi2Mo, the required molten steel can be poured into a 15t bottom pouring ladle used for casting, and the molten steel with a chemical composition of 0.37%≤C content≤0.43%, 0.30%≤Si content≤0.50%, 0.70%≤Mn content≤1.00%, P content≤0.025%, S content≤0.025%, 1.00%≤Cr content≤1.40%, 1.40%≤Ni content≤1.70%, and 0.30%≤Mo content≤0.40% can be completed.

[0030] In step (4), the outlet diameter of the 15t ladle is φ70mm.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] 1) The present invention can effectively solve the problem of low casting yield by tilting casting, reduce the amount of risers used, greatly reduce the difficulty of casting cleaning, effectively improve the productivity of operators, and directly improve the surface quality of the hexagonal cavity of the casting.

[0033] 2) The spherical panel manufactured by the method of the present invention has a hexagonal cavity vertical plate structure, simple shape, excellent surface quality, and can meet the requirements of ultrasonic secondary flaw detection.

[0034] 3) The present invention is easy to implement and can meet the requirements of stable production. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a schematic structural diagram of an upper mold and a surface structure of a spherical panel casting mold.

[0036] Figure 2The present invention is a schematic structural diagram of a lower mold and surface structure of a spherical panel casting mold.

[0037] In the figure: upper mold 1, lower mold 2, riser 3, ingates 4, runner 5, lifting handle 6, sprue 7, riser pad 8, chiller 9, air eye 10, inspection block 11, casting cavity 12, hexagonal cavity 13, spherical protrusion 14, vertical plate 15, plate body 16. DETAILED DESCRIPTION

[0038] The present invention will be further described below in conjunction with the accompanying drawings.

[0039] The present invention discloses a casting mold for a spherical panel casting, comprising an upper mold and an upper template and a lower mold and a lower template. A casting cavity is arranged on the surface of the upper template, the casting cavity is composed of a plurality of hexagonal cavities, an entgate is arranged on one side of the casting cavity, a riser is arranged on the surface of the upper template, an air eye is arranged on a hexagonal cavity vertical plate on the surface of the upper template away from the entgate, and a straight runner is arranged on the surface of the upper template; a plate body is arranged on the surface of the lower template, a spherical protrusion is arranged on the surface of the plate body, a vertical plate is arranged on one side of the plate body, a cross runner is arranged on the other side of the plate body, and an entgate is arranged between the cross runner and the plate body.

[0040] A lifting handle and a testing block are arranged on one side of the vertical plate.

[0041] A chill is placed in the hexagonal cavity.

[0042] The specification of the riser is φ180*500.

[0043] The material of the cold iron is Q235.

[0044] There are seventeen risers, three of which are connected to the ingrowth; the remaining risers are in the hexagonal cavity, and riser pads are arranged below.

[0045] The riser specification is φ180*500 and the thickness is 25mm.

[0046] The material of the cold iron is Q235.

[0047] A ball face plate casting method comprises the following steps:

[0048] ⑴ Making mold

[0049] According to the size requirements of the drawing, make a set of ball panel casting molds at a 2% scale;

[0050] ⑵Styling and box assembly

[0051] According to the size of the template, a sand box with a size of 3250*3350*400 is selected, and the reinforcing ribs of the sand box are welded according to the placement position of the riser 3, and then the wooden mold with the release agent is placed on the platform. According to the process requirements, the riser 3 with a size of φ180*500 and a slope of 1:20, the φ80 sprue 7, the φ25 air eye 10, the thick 60 lifting handle 6, the long 220 test block 11, and the φ150*100 cold iron 9 are placed according to the marked positions, and then the sand box is placed on the template, and a certain proportion of sand is started to flow in the sand box. Quartz sand, XY-32 curing agent, and 886N furan resin are placed in a ratio of 100:0.5-0.7:0.9-1.3 using the furan resin sand process for sand molding, and funnel bricks are placed at the position of the upper box sprue 7 for easy casting. When the sand mold strength reaches 0.8-1.0MPa, the mold is removed. , turn over the box, then repair the damaged cavity position, and clean the foam riser 3 and the foam test block 11. After the cavity is repaired, first use a Baume degree of 45-50 paint to brush three times, each coating thickness is 0.6-0.8mm, and then use a Baume degree of 20-30 paint to brush twice, and use fine sandpaper to polish after the last brushing and drying. The cavity can be closed only after there are no cracks or defects; before the closing process, two circles of sealing mud strips should be laid around the sand mold, and after the upper and lower boxes are combined together, first use a 12mm thick steel bar to weld the upper and lower boxes together, and then put the 6t weight on the upper box sand mold to complete the required cavity. Use a high-power hot air blower to blow hot air from the gate, riser 3, air eye 10 and other positions three hours before casting to bake the cavity to above 60°C, that is, complete the preparation work before casting;

[0052] ⑶Smelting and casting

[0053] A 15-ton electric arc furnace is used to add ordinary scrap steel, recycled materials, and alloy materials in a certain proportion to power transmission, and the required molten steel is obtained through oxidation-reduction reaction. The chemical composition of the molten steel is as follows: 0.37%≤C content≤0.43%, 0.30%≤Si content≤0.50%, 0.70%≤Mn content≤1.00%, P content≤0.025%, S content≤0.025%, 1.00%≤Cr content≤1.40%, 1.40%≤Ni content≤1.70%, 0.30%≤Mo content≤0.40%;

[0054] The smelting and casting method is as follows: using a 15-ton electric arc furnace to add scrap steel and recycled materials in a certain proportion and then send electricity, after melting, take samples to analyze the chemical composition, when the C, Si, Mn, S, P and other components meet the requirements, immediately remove the slag, re-add slag-making materials and alloys, send electricity to enter the reduction period, when the temperature is ≥1580℃, take samples to analyze conventional elements, adjust the composition, and when the chemical composition is qualified, quickly heat up to 1650-1670℃ to start tapping, and when the molten steel is turned into the 15-ton ladle, first Aluminum ingots for deoxidation are added, and then fluorite and slag-making agent for diluting slag are added. After the steel tapping is completed, argon is blown from the bottom of the molten steel for at least 2 minutes. When the temperature of the molten steel drops to 1560-1575°C, it is hoisted and transported to the casting area, and the ladle water mouth is aligned with the horn. Under the condition of a casting time of 90s-150s, it is poured into the mold cavity through the pouring cup. When the molten steel is about to overflow the riser, the casting is stopped, and a layer of riser covering agent with a thickness of about 25mm is applied on the surface of the riser 3;

[0055] ⑷ Annealing and cleaning

[0056] First, the cavity of the ball panel that has been naturally insulated for 24 hours is opened, and the weight on the upper box is lifted. Then, when the insulation time is about 40 hours, the casting is lifted out by a crane, and then a complete annealing treatment is performed for 9 hours. After the casting is cooled to 200-150°C with the furnace, it is air-cooled. When the temperature of the casting is completely reduced to room temperature, the riser 3 is hammered and removed with an air hammer. Then, the uneven parts at the root of the riser 3 are cut flat with an air cutting gun and a carbon arc air planer. Finally, the required ball panel blank can be obtained through grinding, cleaning, shot blasting, finishing, sand blasting and other processes. Finally, the obtained blank is subjected to heat treatment, shot blasting, processing, painting, and packaging to obtain a finished ball panel.

Claims

1. A casting mold for a spherical panel casting, comprising an upper mold (1) and an upper mold plate and a lower mold (2) and a lower mold plate, wherein the casting is divided into three parts, namely a solid hemispherical structure at the bottom, a flat plate structure in the middle, and a vertical plate structure at the top, characterized in that: A casting cavity (12) is arranged on the surface of the upper template, the casting cavity (12) is composed of a plurality of hexagonal cavities (13), an entgate (4) is arranged on one side of the casting cavity (12), a riser (3) is arranged on the surface of the upper template, an air eye (10) is arranged on a vertical plate of the hexagonal cavity (13) on the side of the upper template surface away from the entgate (4), and a straight runner (7) is arranged on the surface of the upper template; a plate body (16) is arranged on the surface of the lower template, a spherical protrusion (14) is arranged on the surface of the plate body (16), a vertical plate (15) is arranged on one side of the plate body (16), a horizontal runner (5) is arranged on the other side of the plate body (16), and an entgate (4) is arranged between the horizontal runner (5) and the plate body (16); a lifting handle (6) and a test block (11) are arranged on one side of the vertical plate (15); and a chiller (9) is placed in the hexagonal cavity (13).

2. A casting mold for a spherical panel casting as claimed in claim 1, characterized in that: The specification of the riser (3) is φ180*500mm.

3. The casting mold for a spherical panel casting according to claim 1, characterized in that: The material of the cold iron (9) is Q235.

4. A method for casting a spherical face plate casting, comprising the casting mold according to claim 1, characterized in that: The casting method comprises the following steps: ⑴ Making mold According to the size requirements of the drawing, a set of ball panel casting molds are made in scale; ⑵ Cavity production Put quartz sand, furan resin and curing agent into sand molding. When the strength of the sand mold reaches the requirement after reaction, the mold can be removed and the box can be turned over. The mold cavity is repaired, sanded and polished. Then the inner wall of the sand mold cavity is painted. After the painting is completed, the paint is ignited. After the burning is completed, the cavity is repaired and the box can be closed. ⑶Steel smelting The scrap steel is mixed with other furnace materials and smelted in an electric arc furnace to obtain molten steel through oxidation-reduction reaction; ⑷ Molten steel casting Before pouring the molten steel into the ladle, aluminum ingots and fluorite are added to the ladle in sequence. After the molten steel is turned into the ladle, argon gas is introduced to purify the molten steel. When the argon is blown until the molten steel reaches a certain temperature, the processed molten steel can be obtained. (5) Casting cleaning The processed molten steel is hoisted to the casting area, the casting temperature and casting time are controlled, and then it is injected into the cavity through the casting inlet. After casting, it is kept warm for 36-42 hours under natural conditions; then the cavity is opened, the casting is hoisted out with a crane, and then it is completely annealed. After the casting is cooled to a certain temperature with the furnace, it is air-cooled. When the temperature of the casting is completely reduced to room temperature, the riser is hammered and cleaned with an air hammer, and then the uneven parts of the riser pad at the root of the riser are cut flat with a gas cutting gun. Finally, after grinding, cleaning, finishing, sandblasting, quenching, processing, and flaw detection processes, the required ball panel product can be obtained.

5. A method for casting a spherical face plate according to claim 4, characterized in that: In the step (2), the ratio of quartz sand, furan resin and curing agent is 100:0.9-1.3:0.5-0.

7.

6. A method for casting a spherical face plate according to claim 4, characterized in that: In the step (2), the paint application method is to first apply three coats of paint with a Baume degree of 45-50, and then apply two coats of paint with a Baume degree of 20-30. After each coat, the surface of the paint needs to be baked with ignited gas. When applying the paint for the fourth and fifth coats, the surface of the paint layer needs to be polished after baking until the surface of the paint layer is smooth.

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