Improvement device for die splitting position of bellmouth end face die of nodular cast iron pipe fitting casting

Abstract

The utility model discloses an improved device for a die splitting position of a nodular cast iron pipe fitting casting bellmouth end face die, which comprises a nodular cast iron pipe fitting casting, and a formed outer die sand mold is wrapped outside the nodular cast iron pipe fitting casting and is used for forming the external shape of the nodular cast iron pipe fitting casting; a sand core is placed in an inner cavity of the nodular cast iron pipe fitting casting; and a positioning core head is arranged between the formed outer mold sand mold and the sand core and is used for positioning and supporting the sand core, so that the accurate position of the sand core in a casting mold is ensured. The parting surface of the mold is moved outwards, so that a casting blank is moved to the edge of the end surface of the casting, the inner cavity and the end surface of the casting are formed by the sand core, the sand core is a resin sand core, the surface of the sand core is coated, and the quality and smoothness of the end surface of the casting and the surface of the inner cavity are better. Blanks and flashes are concentrated on the edge of the casting at the parting position of the casting, polishing is convenient, and time and labor are saved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a mould parting position design technical field, concretely is an improved device of a nodular cast iron pipe fitting casting socket end face mould parting position. BACKGROUND

[0002] The nodular cast iron pipe fitting quality requires that the spheroidization grade control of the pipe fitting is greater than 80%, so that the mechanical performance of the material itself is improved, and the nodular cast iron pipe fitting has the nature of iron and the performance of steel. The nodular cast iron pipe fitting has the nature of iron and the performance of steel, excellent corrosion resistance, good ductility, good sealing effect, easy installation, and is mainly used for municipal, industrial and mining enterprise water supply, gas transmission, oil transmission and the like, and has high performance price ratio. The nodular cast iron tee pipe fitting accounts for about 25% of the nodular cast iron pipe fitting. The present application aims to change the mould parting surface position during mould design, and improve the casting polishing efficiency.

[0003] Casting is to melt metal, manufacture a casting mold, and pour molten metal into the casting mold to solidify into a metal blank part with a certain shape, size and mechanical property. The green sand casting is the most commonly used and economical molding. The sand box is placed on the mold, and the green sand is added into the sand box. The outer contour of the casting is formed by compaction and demolding. The inner contour of the casting part is formed by core making. In order to accurately position the sand core, a positioning core head needs to be designed. There is a cooperation gap between the outer mold positioning core head and the sand core core head, which prevents the sand from being rubbed and dropped during core setting and box closing, and produces a sand dropping waste product. During mould design, how to design the parting surface (the boundary between the sand core and the outer mold) has a great influence on the polishing of the casting blank. Improper design of the parting surface position directly affects the polishing efficiency and cost of the casting. The parting surface of the mould designed by the prior art is in the middle of the casting end face. When polishing, the resistance of the grinding wheel is large. When the molding equipment and the box closing are abnormal, the casting process will have the problem of misalignment. The polishing amount of the casting blank is larger, which directly affects the polishing efficiency. CONTENT OF THE UTILITY MODEL

[0004] (I) Technical problem solved

[0005] In view of the defects of the prior art, the utility model provides an improved device for the parting position of the nodular cast iron pipe fitting casting socket end face mould, which changes the parting surface position of the mould, moves the parting surface to the edge of the casting end face, and solves the problem of excessive polishing amount in the above background technology.

[0006] (II) Technical scheme

[0007] In order to achieve the above object, the utility model discloses an improved device of the parting position of the end face mould of nodular cast iron pipe fitting casting, which is implemented through the following technical scheme: a nodular cast iron pipe fitting casting is provided, and the nodular cast iron pipe fitting casting is externally wrapped with a formed outer mould sand type for forming the external shape of the nodular cast iron pipe fitting casting; a sand core is placed in the inner cavity of the nodular cast iron pipe fitting casting for placing the sand core into the cavity of the nodular cast iron pipe fitting casting, and after liquid spherulitic molten iron is poured, the sand core surrounded by the liquid metal finally forms a specific shape and structure inside the pipe fitting casting; a positioning core head is arranged between the formed outer mould sand type and the sand core, which plays a role of positioning and supporting the sand core and ensures the accurate position of the sand core in the casting.

[0008] Preferably, the positioning core head is provided with a core head joint seam at the matching position of the outer mould sand type and the positioning core head, and the size of the joint seam directly affects the positioning accuracy of the positioning core head, the stability of the sand core and the quality of the nodular cast iron pipe fitting casting.

[0009] Preferably, the diameter of the sand core is 395.3mm.

[0010] Preferably, the gap between the outer mould sand type and the sand core in the diameter direction is 0.2mm on one side, the gap thickness of the pressure ring on the positioning core head is 0.6mm, and the length is about 10mm.

[0011] Preferably, the sand core is a resin sand core, and the surface of the sand core is immersed with paint.

[0012] (Three) beneficial effects

[0013] The utility model discloses an improved device of the parting position of the end face mould of nodular cast iron pipe fitting casting. The following beneficial effects are possessed:

[0014] 1. The utility model discloses an improved device of the parting position of the end face mould of nodular cast iron pipe fitting casting. The following beneficial effects are possessed:

[0015] 2. The utility model discloses an improved device of the parting position of the end face mould of nodular cast iron pipe fitting casting. The following beneficial effects are possessed:

[0016] 3. The utility model discloses an improved device of the parting position of the end face mould of nodular cast iron pipe fitting casting. The following beneficial effects are possessed: DRAWINGS

[0017] Figure 1 The structure diagram of the parting position of the end face mould of nodular cast iron pipe fitting casting is shown in the figure.

[0018] Figure 2 Enlarged schematic diagram of the grout seam for positioning the core head between the improved outer mold and the sand core;

[0019] Figure 3 A schematic diagram of the improved mold positioning core structure;

[0020] Figure 4 Enlarged schematic diagram of the grout seam for improving the positioning core head between the outer mold and the sand core;

[0021] In the diagram: 1. Outer mold sand mold, 2. Positioning core head, 3. Sand core, 4. Ductile iron pipe fitting casting, 5. Positioning core head filler. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please see Figures 1-2 This utility model provides a technical solution: an improved device for the mold parting position of the socket end face mold of ductile iron pipe fittings.

[0024] like Figure 1 As shown, the casting includes a ductile iron pipe fitting 4. The ductile iron pipe fitting 4 is surrounded by a formed outer sand mold 1, which is used to form the external shape of the ductile iron pipe fitting 4. A sand core 3 is placed inside the cavity of the ductile iron pipe fitting 4. The sand core is placed into the cavity of the ductile iron pipe fitting 4. After the molten ductile iron is poured, the sand core surrounded by the molten metal will eventually form the specific shape and structure inside the pipe fitting casting. A positioning core head 2 is provided between the formed outer sand mold 1 and the sand core 3. Its function is to position and support the sand core and ensure the accurate position of the sand core in the mold.

[0025] There is a locating core head slit 5 at the mating point between the outer mold sand mold 1 and the locating core head 2. The size of this slit directly affects the positioning accuracy of the locating core head 2, the stability of the sand core 3, and the quality of the ductile iron pipe casting 4.

[0026] The diameter of sand core 3 is Ф395.3mm. Sand core 3 is a resin sand core, and its surface is impregnated with coating.

[0027] The diameter clearance between the outer mold sand mold 1 and the sand core 3 is 0.2mm on one side, and the anti-pressure ring on the positioning core head 2 has a thickness of 0.6mm and a length of about 10mm.

[0028] As shown in Figure 3, the mold positioning core parting position before the improvement is in the middle of the end face of the ductile iron pipe fitting casting (4). The diameter of the end face of the outer mold (1) is Ф396.5mm; the outer diameter of the end face of the sand core (3) is Ф359.5mm and the inner diameter is Ф290.4mm. When the current molding demolding is not complete, after the core is lowered, after the upper and lower boxes are closed, the cumulative tolerance of the positioning of molding, box closing, etc. is biased to one end, causing the ductile iron pipe fitting casting ( 4) Uneven end face. The end face of the ductile iron pipe fitting (4) is formed by the outer mold (1) with a surface area of ​​about 220 square centimeters, and the other part is formed by the sand core (3) with a surface area of ​​about 355 square centimeters. This results in a step on the end face, which needs to be ground flat. The two ends need to be ground for about 575 square centimeters more, which increases the grinding time and wastes grinding materials. The mold misalignment is 0.5mm, which requires grinding away about 0.6 kg of iron, increasing the manufacturing cost.

[0029] An improved device for the mold parting position of the socket end face mold of a ductile iron pipe fitting includes a ductile iron pipe fitting casting 4, a ductile iron pipe fitting outer mold 1, and a core box mold parting position design to form the inner and outer shapes of the ductile iron pipe fitting. During the manufacturing process of the ductile iron pipe fitting, upper and lower molds are formed. A sand core 3 is placed in the lower mold to form the inner cavity of the casting. The upper and lower molds are closed. The cavity formed by the outer mold 1 and the sand core 3 form the pipe fitting outline. Liquid ductile iron is poured into the casting station, and after cooling, the casting is formed. The sand core 3, surrounded by liquid metal, forms the specific shape and structure inside the pipe fitting casting. A positioning core head is provided between the cavity formed by the outer mold and the sand core, which serves to position and support the sand core, ensuring the accurate position of the sand core in the mold.

[0030] like Figure 2 As shown, the improved mold positioning core head parting position is designed to be at the edge of the casting end face. The diameter of the sand core (3) core head is increased from Ф359.5mm to Ф395.3mm. The clearance between the outer mold (1) and the sand core (3) in the diameter direction is 0.2mm on one side. The anti-pressure ring on the positioning core head (2) has a clearance thickness of 0.6mm and a length of about 10mm. After the improvement, the positioning core head grout (5) is at the edge of the end face of the ductile iron pipe fitting casting (4). The grinding area is reduced to 7.5 square centimeters, making the grinding grout easier.

[0031] In summary, by moving the mold parting surface outward, the filler seams of the casting blank are moved to the edge of the casting end face. The inner cavity and end face of the casting are formed by a sand core. The sand core is a resin-based sand core with a coating on its surface, resulting in a better surface finish for the casting end face and inner cavity. The filler seams and flash at the mold parting point are concentrated at the edge of the casting, making grinding convenient and saving time and effort.

[0032] The burr cuts in the casting blanks are significantly reduced, the end face finish of the castings is better, the amount of grinding required is less, the average grinding time per casting is reduced by 3 minutes, and the service life of the grinding wheel on the grinding machine is extended. The end face quality of the castings is better; the burrs and flash in the casting burr cuts are smaller; grinding efficiency is improved, the life of the grinding wheel on the grinding machine is extended, and production costs are saved.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An improved device for the mold parting position of the socket end face mold of a ductile iron pipe fitting, comprising a ductile iron pipe fitting casting (4), characterized in that: The ductile iron pipe casting (4) is wrapped with an outer sand mold (1) to form the external shape of the ductile iron pipe casting (4); a sand core (3) is placed in the inner cavity of the ductile iron pipe casting (4) to place the sand core into the cavity of the ductile iron pipe casting (4). After the liquid ductile iron is poured, the sand core surrounded by the liquid metal will eventually form the specific shape and structure inside the pipe casting; a positioning core head (2) is provided between the outer sand mold (1) and the sand core (3), which plays the role of positioning and supporting the sand core to ensure the accurate position of the sand core in the mold.

2. The improved device for determining the mold parting position of the socket end face mold of ductile iron pipe fittings according to claim 1, characterized in that: The outer mold sand mold (1) and the positioning core head (2) have a positioning core head slit (5). The size of the slit directly affects the positioning accuracy of the positioning core head (2), the stability of the sand core (3), and the quality of the ductile iron pipe casting (4).

3. The improved device for determining the mold parting position of the socket end face mold of ductile iron pipe fittings according to claim 1, characterized in that: The diameter of the sand core (3) is Ф395.3mm.

4. The improved device for determining the mold parting position of the socket end face mold of ductile iron pipe fittings according to claim 1, characterized in that: The gap between the outer mold sand pattern (1) and the sand core (3) in the diameter direction is 0.2mm on one side, and the anti-pressure ring on the positioning core head (2) has a thickness of 0.6mm and a length of about 10mm.

5. The improved device for determining the mold parting position of the socket end face mold of ductile iron pipe fittings according to claim 1, characterized in that: The core (3) is a resin core, and the surface of the core (3) is coated with a paint.

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