CN211758337U

CN211758337U - Countersunk sand core

Info

Publication number: CN211758337U
Application number: CN202020123997.0U
Authority: CN
Inventors: 周宁; 张亚敏; 项铮宇; 徐莉雄
Original assignee: Ningbo Tuotie Machinery Co ltd
Current assignee: Ningbo Tuotie Machinery Co ltd
Priority date: 2020-01-19
Filing date: 2020-01-19
Publication date: 2020-10-27
Anticipated expiration: 2030-01-19

Abstract

A counter bore psammitolite which characterized in that: the support frame is composed of hollow steel pipes, and resin sand layers are coated on the side faces and the closed ends of the hollow steel pipes; one end of the hollow steel pipe is provided with an opening, a first supporting rib is transversely arranged in the hollow steel pipe close to the opening end, and two ends of the first supporting rib are lapped on the side wall of the hollow steel pipe; the other end of the hollow steel pipe is arranged in a closed manner, the end is positioned at the bottom of the high-pressure cylinder, a plurality of second supporting ribs which are mutually lapped along the radial surface of the steel pipe are also arranged at the end, the second supporting ribs are fixed on a fixing column which is arranged along the axial direction of the steel pipe, and a space is arranged between the plurality of second supporting ribs and the closed end of the steel pipe; the method has the advantages of less resin sand consumption, high strength and difficult occurrence of casting defects.

Description

Countersunk sand core

Technical Field

The utility model relates to a gating system technical field, specificly relate to a counter sink psammitolite.

Background

The large-scale cylinder casting is formed by pouring high-temperature molten iron into a cavity and then cooling and molding the molten iron; the casting is often required to be provided with a large-size high-pressure cylinder, for example, the size of the casting of the oil cylinder is 2170mm multiplied by 970mm multiplied by 926mm, the weight of the casting of the oil cylinder reaches 2.17 tons, two high-pressure cylinders with the aperture diameter of 300mm multiplied by 930mm (long) are required to be poured on the casting, the oil leakage of the high-pressure cylinder under the high-pressure condition is also ensured, and the oil pressure resistance is required to be 25 Mpa; the difficulty is brought to the casting process, and the defects of air holes, concave-convex and the like are mainly required to be avoided as much as possible in the high-pressure cylinder; the large-sized high-pressure cylinder needs to be formed through a sand core, namely, the sand core is preset at the position in a pouring system of an oil cylinder casting, molten iron surrounds the sand core to fill the hole diameter of the high-pressure cylinder, the sand core is formed by mixing resin sand, and the weight of the sand core with the size can reach about 100kg, so that the large-sized high-pressure cylinder has the defect of inconvenient transportation; meanwhile, the sand core with the structure has the defects that the sand core is damaged under the action of the impact force and the like due to the fact that the resin sand is large in using amount, low in strength, large in casting model and large in impact force of molten iron, casting defects are caused on the inner wall of the high-pressure cylinder, and the defects that oil leakage, high oil pressure resistance and the like easily occur to subsequent castings when the sand core is used are overcome.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to prior art's the aforesaid is not enough, provides a counter sink psammitolite that the resin sand quantity is few, intensity is high, be difficult to the casting defect appear.

In order to solve the technical problem, the utility model discloses a technical scheme as follows: a counter bore sand core comprises a support frame formed by hollow steel pipes, wherein resin sand layers are coated on the side faces and the closed ends of the hollow steel pipes; one end of the hollow steel pipe is provided with an opening, a first supporting rib is transversely arranged in the hollow steel pipe close to the opening end, and two ends of the first supporting rib are lapped on the side wall of the hollow steel pipe; the other end of the hollow steel pipe is arranged in a closed mode, the end is located at the bottom of the high-pressure cylinder, a plurality of second supporting ribs which are mutually overlapped along the radial surface where the steel pipe is located are further arranged at the end, the second supporting ribs are fixed on fixing columns which are arranged along the axial direction of the steel pipe, and a distance is arranged between the plurality of second supporting ribs and the closed end of the steel pipe.

By adopting the structure, the defect of large using amount of the traditional resin sand is overcome, the weight of the whole sand core can be reduced, the carrying is convenient, and meanwhile, the using amount of the resin sand is reduced, and the production cost is reduced; more importantly, a plurality of second supporting ribs which are mutually lapped along the radial surface of the steel pipe are arranged at the end part of the hollow steel pipe positioned at the bottom of the high-pressure cylinder, a space is arranged between each second supporting rib and the closed end of the steel pipe, then resin sand is filled in the hollow steel pipe, and the resin sand can respectively wrap the two sides of each second supporting rib inside and outside the second supporting ribs to form integral resin sand; the arrangement strengthens the firmness of the resin sand, particularly the positions of edges and corners, is not easy to cause the phenomenon of scouring damage, and can not cause casting defects caused by insufficient molten iron amount at the position because molten iron is poured into cracks due to resin sand cracks; the arrangement of the gap between the bottom end and the bottom end can improve the contact area with the resin sand so as to improve the adhesion fastness with the hollow steel, thereby effectively ensuring that slag (such as a coating layer and sand) cannot fall off in the molten iron impact process and improving the strength of the whole sand core; in addition, the hollow steel pipe coated with the resin sand on the outer layer of the hollow steel pipe is similar to a chilling block structure, so that the cooling speed of molten iron in a pouring system at the position can be increased, the consistency with the cooling speed of molten iron at other positions is ensured, and the performance consistency of the whole casting is improved.

Preferably, the thickness of the resin sand layer is 25-35mm, and further 30 mm; the thickness can meet the requirement of surface roughness Ra0.8 microns of the high-pressure cylinder, the oil pressure resistance is improved, and oil leakage and oil seepage are prevented.

Preferably, the first supporting rib extends along the radial direction of the hollow steel pipe; by adopting the structure, the supporting function of the first supporting rib can be further improved, and the deformation of the hollow steel pipe under the action of high temperature and impact force in the pouring process is prevented.

Preferably, the plurality of second support ribs are 6, and include three second support ribs arranged transversely and three second support ribs arranged longitudinally, and a transverse second support rib and a longitudinal second support rib which are located at the middle position are perpendicular to each other and extend along the radial direction of the hollow steel tube. Adopt this structure, overlap joint 6 second brace rods each other and two middle longest extend to the outer wall department of steel pipe, constitute cross type frame, then overlap joint two short second brace rods on horizontal and fore-and-aft two second brace rods separately respectively again, form the frame construction of a fretwork, in the cladding resin sand layer, can realize with the bigger area of contact of resin sand, improve the firmness between resin sand and the hollow steel pipe.

Preferably, the closed end of the hollow steel pipe is fixed with an axially extending fixing column, and the second support rib is connected to the fixing column; this setting can expose the surface of many second brace rods as far as outside, improves the area of contact with the resin sand to improve the firmness.

Preferably, the number of the fixing columns is 5, and the fixing columns are respectively positioned at the center of the bottom surface of the hollow steel pipe and at positions close to four edges; thereby improving the fixing effect on the second supporting ribs and being firmer and more stable.

Preferably, a plurality of reinforcing ribs extend along the axial direction on the outer surface of the hollow steel pipe; adopt this structure can improve the intensity of whole core bone, can also improve the area of contact of resin sand and steel pipe simultaneously for resin sand laminating is more firm.

Drawings

Fig. 1 a schematic structural view (angle 1) of a core bar of a counter-sunk sand core according to the present application.

Fig. 2 a schematic structural view (angle 2) of the core bar of the counter-sunk sand core of the present application.

FIG. 3 the core rod of the counter bore sand core of the present application is shown schematically (Angle 3)

FIG. 4 is a schematic structural view of a cross-sectional view of the countersunk sand core after the surface of the core is coated with resin sand.

Fig. 5 is a schematic structural diagram of the cylinder casting according to the embodiment.

FIG. 6 is a schematic diagram of a cylinder casting according to an embodiment of the present application (see inside the counterbore).

As shown in the attached drawings: 1. the hollow steel pipe, 1.1 the first brace muscle, 1.2 the second brace muscle, 2 resin sand layer, 3 the fixed column, 4 the strengthening rib.

Detailed Description

The present application will be described in further detail with reference to the following drawings and specific examples, but the present application is not limited to the following examples. The casting cavity is a space for forming the casting, the structure of the casting cavity is completely matched with the casting, and the casting cavity can be understood as each position of the casting.

The concrete structure of the corresponding oil cylinder casting of this embodiment is shown in fig. 5-6, the size of the casting is 2170 × 970 × 926mm, the weight is 2.17 tons, the casting has 2 high-pressure cylinders with the aperture diameter of 300 × 930mm, the high-pressure cylinders are guaranteed not to leak oil, the oil pressure resistance is 25Mpa, and the high-pressure cylinders are formed by the sand cores supported by the core frame of this application. In order to ensure that the pressure cylinder can not leak oil, the sand core at the aperture part of phi 300 multiplied by 930mm is made by mixing a hollow steel pipe with the outer diameter of phi 240mm and resin sand with the thickness of 30mm coated on the outer layer of the hollow steel pipe, so as to accelerate the cooling speed, meet the requirement of surface roughness Ra0.8 mu m (micrometer) of the high-pressure cylinder, reduce the using amount of the resin sand and reduce the production cost. In order to enhance the adhesion fastness of the steel pipe at the bottom of the sand core and the resin sand, the bottom of the steel pipe is hollowed out by a phi 10mm steel bar.

The concrete structure of the sand core is shown in the attached figures 1-4, the counter sink sand core of the embodiment comprises a support frame formed by hollow steel pipes 1, wherein the side surfaces (namely the outer side surfaces, namely the outer side surfaces extending in the axial direction) and the closed ends (one end of each hollow steel pipe is open and the other end is closed) of each hollow steel pipe are coated with resin sand layers 2; one end of the hollow steel pipe is provided with an opening, a first supporting rib 1.1 is transversely arranged in the hollow steel pipe close to the opening end, and two ends of the first supporting rib are lapped on the side wall of the hollow steel pipe; the other end of the hollow steel pipe is arranged in a closed mode, the end is located at the bottom of the high-pressure cylinder, a plurality of second supporting ribs 1.2 which are mutually lapped along the radial surface where the steel pipe is located are further arranged at the end, the second supporting ribs are fixed on a fixing column 3 which is arranged along the axial direction of the steel pipe, and a space is formed between the plurality of second supporting ribs and the closed end of the steel pipe.

The closed section of the hollow steel pipe is positioned in the high-pressure cylinder shown in the attached figures 5-6 and is in contact with the bottom of the high-pressure cylinder.

By adopting the structure, the defect of large using amount of the traditional resin sand is overcome, the weight of the whole sand core can be reduced, the carrying is convenient, and meanwhile, the using amount of the resin sand is reduced, and the production cost is reduced; more importantly, a plurality of second supporting ribs which are mutually lapped along the radial surface of the steel pipe are arranged at the end part of the hollow steel pipe positioned at the bottom of the high-pressure cylinder, a space is arranged between each second supporting rib and the closed end of the steel pipe, then resin sand is filled in the hollow steel pipe, and the resin sand can respectively wrap the two sides of each second supporting rib inside and outside the second supporting ribs to form integral resin sand; the arrangement strengthens the firmness of the resin sand, particularly the positions of edges and corners, is not easy to cause the phenomenon of scouring damage, and can not cause casting defects caused by insufficient molten iron amount at the position because molten iron is poured into cracks due to resin sand cracks; the arrangement of the gap between the bottom end and the bottom end can improve the contact area with the resin sand so as to improve the adhesion fastness with the hollow steel, thereby effectively ensuring that no slag falls off in the molten iron impact process and improving the strength of the whole sand core; in addition, the hollow steel pipe coated with the resin sand on the outer layer of the hollow steel pipe is similar to a chilling block structure, so that the cooling speed of molten iron in a pouring system at the position can be increased, the consistency with the cooling speed of molten iron at other positions is ensured, and the performance consistency of the whole casting is improved.

The thickness of the resin sand layer is 25-35mm, and the thickness of the resin sand layer in the embodiment is 30 mm; the thickness can meet the requirement of surface roughness Ra0.8 microns of the high-pressure cylinder, the oil pressure resistance is improved, and oil leakage and oil seepage are prevented.

As shown in fig. 3, the first support rib 1.1 extends along the radial direction of the hollow steel pipe 1; adopt this structure can further improve the supporting role of first support muscle, prevent the deformation of casting process hollow steel pipe under high temperature and impact action, the setting of this first support muscle can also play the effect of lifting by crane hollow steel pipe simultaneously, and radial extension can improve the stationarity when lifting by crane.

As shown in fig. 1-2, the number of the second support ribs 1.2 is 6, and the second support ribs include three second support ribs arranged transversely and three second support ribs arranged longitudinally, and one transverse second support rib located at the middle position and one longitudinal second support rib located at the middle position are perpendicular to each other and extend along the radial direction of the hollow steel tube. By adopting the structure, 6 second supporting ribs are mutually lapped, and the two middle second supporting ribs extend to the position close to the outer wall of the hollow steel pipe to form a cross-shaped frame, and then two short second supporting ribs are respectively lapped on the second supporting ribs at the middle positions in the transverse direction and the longitudinal direction to form a hollow frame structure; the interval has between the bottom surface of this end of frame that this many second brace rods constitute and hollow steel pipe, and this kind of structure can realize the bigger area of contact with the resin sand in the cladding resin sand layer, improves the firmness between resin sand and the hollow steel pipe.

As shown in the attached drawings 1-2, a fixed column 3 extending axially is fixed on the closed end of the hollow steel tube 1, and the second support rib is connected to the fixed column; this setting can expose the surface of many second brace rods as far as outside, improves the area of contact with the resin sand to improve the firmness.

As shown in fig. 1-2, the number of the fixing columns in this embodiment is 5, and the fixing columns are respectively located at the center of the bottom surface of the hollow steel pipe and at positions close to four sides; thereby improving the fixing effect on the second supporting ribs and being firmer and more stable.

As shown in fig. 1-4, a plurality of reinforcing ribs extend along the axial direction on the outer surface of the hollow steel pipe; adopt this structure can improve the intensity of whole core bone, can also improve the area of contact of resin sand and steel pipe simultaneously for resin sand laminating is more firm.

Claims

1. A counter bore psammitolite which characterized in that: the support frame is composed of hollow steel pipes, and resin sand layers are coated on the side faces and the closed ends of the hollow steel pipes; one end of the hollow steel pipe is provided with an opening, a first supporting rib is transversely arranged in the hollow steel pipe close to the opening end, and two ends of the first supporting rib are lapped on the side wall of the hollow steel pipe; the other end of the hollow steel pipe is arranged in a closed mode, the end is located at the bottom of the high-pressure cylinder, a plurality of second supporting ribs which are mutually overlapped along the radial surface of the steel pipe are further arranged at the end and fixed on fixing columns which are arranged in the axial direction of the steel pipe, and a distance is arranged between the plurality of second supporting ribs and the closed end of the steel pipe.

2. The counterbore sand core of claim 1, wherein: the thickness of the resin sand layer is 25-35 mm.

3. The counterbore sand core of claim 2, wherein: the thickness of the resin sand layer is 30 mm.

4. The counterbore sand core of claim 1, wherein: the first supporting rib extends along the radial direction of the hollow steel pipe.

5. The counterbore sand core of claim 1, wherein: the plurality of second support ribs are 6, and comprise three transversely arranged second support ribs and three longitudinally arranged second support ribs, and one transverse second support rib and one longitudinal second support rib which are positioned in the middle are perpendicular to each other and extend along the radial direction of the hollow steel pipe.

6. The counterbore sand core of claim 1, wherein: the closed end of the hollow steel pipe is fixedly provided with a fixing column extending axially, and the second support rib is connected to the fixing column.

7. The counterbore sand core of claim 6, wherein: the number of the fixing columns is 5, and the fixing columns are respectively positioned at the center of the bottom surface of the hollow steel pipe and close to the four sides of the bottom surface of the hollow steel pipe.

8. The counter bore sand core of any one of claims 1 to 7, wherein: the outer surface of the hollow steel pipe extends along the axial direction to form a plurality of reinforcing ribs.