WO2018039854A1

WO2018039854A1 - Casting mould for hydraulic valve body used in large loader and manufacturing method therefor

Info

Publication number: WO2018039854A1
Application number: PCT/CN2016/097129
Authority: WO
Inventors: 丁洋
Original assignee: 丁洋
Priority date: 2016-08-29
Filing date: 2016-08-29
Publication date: 2018-03-08

Abstract

Disclosed is a casting mould for a hydraulic valve body used in a large loader, the casting mould comprising a cope and a draft, a sand core and a gating and risering system. The sand core comprises a core head (1), a main core (2) and small cores (3). The main core (2) is composed of seven longitudinal core skeletons and four transverse core skeletons horizontally arranged in one and the same plane. A plurality of protruding blocks are provided on the main core (2), with mounting grooves being provided in the protruding blocks, and the small cores (3) are fixed to the main core (2) by the mounting grooves. The gating and risering system comprises two exothermic and thermal insulating risers 90 mm in diameter and 120 mm in height. The casting mould for a hydraulic valve body used in a large loader has a rational and compact structure with high reliability, and is convenient for assembling and casting; the linearity of a main valve hole of a casting blank is controlled to be less than 0.8 mm, thereby avoiding assembly errors of complicated sand cores; the problems of shrinkage cavity, shrinkage porosity, internal gas holes and other casting defects of castings are solved; and the compactness of the internal structure is improved, thus achieving zero leakage under a high pressure working state where the design pressure is greater than or equal to 35 Mpa, so that the first pass yield of castings is greatly improved, and the costs of casting are lowered.

Description

Large-scale loader hydraulic valve body casting mold and manufacturing method thereof

Technical field

The invention relates to the technical field of mechanical equipment manufacturing, in particular to a large loader hydraulic valve body casting mold and a manufacturing method thereof.

Background technique

Most of today's large loaders have hydraulic control systems. The hydraulic system consists of hydraulic pumps, control valves, hydraulic cylinders, hydraulic motors, pipelines, fuel tanks, etc. The hydraulic transmission system transmits the power of the engine to the hydraulic pressure through hydraulic pumps. Actuators such as motors and hydraulic cylinders act to drive the work unit to complete various operations.

The hydraulic valve is a key component of the hydraulic system. The hydraulic valve structure and precision requirements of the large loader are very high, and it is required to have no leakage under the high pressure working condition of pressure ≥35Mpa.

Due to the complicated internal flow passage structure of the valve body casting, it cannot be formed at one time. The sand core needs to be assembled in multiple steps through the main core and many small cores. In the assembly process, gap errors often occur, and the castings may have shrinkage cavities. The casting defects such as shrinkage and internal pores cannot guarantee the compactness of the internal structure. It is easy to leak under the high pressure working condition of pressure ≥35Mpa, resulting in low casting yield and high casting cost.

Summary of the invention

The object of the present invention is to provide a large-sized loader hydraulic valve with reasonable structure, high reliability, high internal organization compactness, convenient assembly and casting, greatly improved product casting yield and reduced casting cost. Body casting mold and manufacturing method.

In order to solve the above technical problems, the present invention provides a large loader hydraulic valve body casting mold, including an upper shell type, a lower shell type, a sand core and a slinging system;

Forming a cavity of a large loader hydraulic valve body with the sand core after the upper shell type and the lower shell type are clamped;

The sand core comprises a core head, a main core and a small core, the core head is a four-frame, and the front and rear side frames are respectively provided Two legs, the main core is horizontally disposed in the core, the core is used for fixedly supporting the main core, and the main core is composed of seven longitudinal cores and four transverse cores horizontally disposed in the same plane. The seven longitudinal core bones include a first longitudinal core, a second longitudinal core, a third longitudinal core, a fourth longitudinal core, a fifth longitudinal core, a sixth longitudinal core, and are arranged in parallel from left to right. a seventh longitudinal core, the fourth transverse core comprising a first transverse core, a second transverse core, a third transverse core and a fourth transverse core aligned in parallel from front to back;

The first longitudinal core to the sixth longitudinal core are connected in a grid shape to the four transverse cores, and the first transverse core to the third transverse core are connected to the seventh longitudinal core, the first The four transverse cores are not connected to the seventh longitudinal core;

a first bump, a second bump, and a third for forming an oil groove are disposed in a region of the first longitudinal core to the sixth longitudinal core between the first lateral core and the second lateral core a bump, a fourth bump and a fifth bump for forming an oil groove in a region of the first longitudinal core to the sixth longitudinal core located between the third lateral core and the fourth transverse core And a sixth bump, a seventh bump for forming an oil groove is disposed on a region of the first longitudinal core to the sixth longitudinal core between the second lateral core and the third transverse core; The first protrusion is provided with an upward first mounting slot, the sixth protrusion is provided with an upward second mounting slot, and the third protrusion is provided with a downward third mounting slot, a fourth mounting slot is disposed on the fourth protrusion. The upper and lower ends of the seventh protrusion are respectively provided with a fifth mounting slot and a sixth mounting slot. The sixth longitudinal core is located on the first transverse core. a seventh mounting groove and an eighth mounting groove are respectively disposed in the region on the bone and the fourth lateral core;

The small core is three layers, from top to bottom: the first layer includes a first small core, the second layer includes six second small cores, and the third layer includes six third small cores, each of which The two small cores are fixed to the main core through the first mounting groove, the second mounting groove and the fifth mounting groove, and each of the third small cores is fixed to the main core through the third mounting groove, the fourth mounting groove and the sixth mounting groove, each a ninth mounting groove is disposed in the middle of the upper surface of the second small core, and the first small core is fixed to the main core through the seventh mounting groove and the eighth mounting groove, and the first small core passes through the ninth mounting slot and the second Small core fixed;

The rigging system comprises two heat-insulating risers and two runners, the heat-insulated riser has a diameter of 90 mm and a height of 120 mm, and the riser is filled with resin sand, and the runner is set at The left and right sides of the upper shell type and the lower shell type.

Specifically, the arcuate faces on the first small core, the six second small cores, and the six third small cores are made of a living block and a core cylinder and are formed at one time.

Specifically, the fifth mounting slot and the sixth mounting slot are circular slots, the first mounting slot, the second mounting slot, the third mounting slot, the fourth mounting slot, the seventh mounting slot, and the eighth mounting The slot and the ninth mounting slot are square slots.

Specifically, the sand core is a high fluidity sand.

Specifically, the seven longitudinal cores are each made of a high alumina ceramic rod having a diameter of 10 mm, and the high alumina ceramic rod has an Al ₂ O ₃ content of 40% to 50%.

Specifically, the sand core assembly gap is controlled by a sand core bonding tooling.

Specifically, the main core is made of a special core mold and integrally formed.

Accordingly, the present invention also provides a method of manufacturing a large-loader hydraulic valve body casting, comprising the following steps:

S1: Inspect the special core mold for making the main core, and clean the dirt on the mold. Use a high-aluminum ceramic rod with a diameter of 10 mm as the seven longitudinal cores on the main core, and Al ₂ O on the high alumina ceramic rod. ₃ content is 40% -50%, using sand as high fluidity sand, heating temperature 180 °C-190 °C, sanding pressure 0.5MPa-0.6MPa, sanding time 5s-7s, curing time 100s-120s;

S2: using a common hydraulic press to make a small core made of a special core making machine, the arc concave surface on the first small core, the second small core and the third small core is made by a live block and a core cylinder and formed once;

S3: Repair all the blunts on the sand core, remove the transition nozzle, fix the main core through the sand core bonding tool, first assemble the bottommost third core to the main core, and after the adhesive is completely solidified, The assembled sand core is turned over and fixed by the sand core bonding tool. The second small core and the third small core are assembled to the main core, the assembly gap of the control sand core is less than 0.1 mm, and then the main core level is set at In the core, there should be no gap between the core and the core interface, and there should be no excess adhesive;

S4: The sand core is horizontally disposed in the upper shell type and the lower shell type, and the upper shell type, the lower shell type and the sand core are clamped to form a cavity of the hydraulic valve body, and the upper shell type and the lower shell type are embedded in the sand box. The cavity between the outer shell of the upper shell type and the lower shell type and the inner side of the sand box is covered with a sand layer, and the sand layer is provided with a pouring system connected with the shell type, and the pouring system adopts two heating and heat insulation risers and two The sprue, the heat-insulating riser has a diameter of 90 mm and a height of 120 mm, and the riser is filled with resin sand;

S5: pouring molten iron index, using a silicon germanium inoculant with a mass fraction of 0.3% and a silicon rare earth inoculant with a mass fraction of 0.2%, in the case of pouring, the molten iron is dispersed into the water through the thin gates on both sides of the upper and lower shells. The pouring temperature is 1380 ° C - 1420 ° C, the pouring time is 25 s-28 s, and the tapping temperature is 1520 ° C - 1540 ° C.

The invention has the following beneficial effects:

1. The hydraulic valve body casting mold structure is reasonable and compact, the reliability is strong, and the assembly and casting are convenient;

2. The high-aluminum ceramic rod with a diameter of 10mm (the content of Al2O3 is 40%--50%) is used as the main channel core, and the straightness of the casting of the main valve hole is controlled to be less than 0.8 mm;

3. The use of high fluidity sand ensures the complete formation and quality of the sand core;

4. Using the sand core bonding tooling, avoiding the assembly error of the complex sand core, and controlling the assembly gap of the sand core within 0.1mm;

5. Resin sand is used between the two risers, and the silicon germanium inoculant is compounded with the silicon rare earth inoculant. The water is injected into the left and right sides of the mold to solve the casting defects such as shrinkage, shrinkage and internal pores of the casting. Internal organization compactness to achieve no leakage under high pressure working conditions with rated pressure ≥35Mpa;

6. The casting pass rate is greatly improved and the casting cost is reduced.

DRAWINGS

In order to more clearly illustrate the technical solutions of the present invention, the drawings used in the embodiments or the description of the prior art will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. Other drawings may also be obtained from those of ordinary skill in the art in light of the inventive work.

Figure 1 is a schematic view showing the first structure of the sand core of the present invention;

Figure 2 is a schematic view showing the second structure of the sand core of the present invention;

Figure 3 is a left side view of the sand core of the present invention:

Figure 4 is a first schematic view of the main core of the present invention;

Figure 5 is a plan view of the main core of the present invention;

Figure 6 is a second schematic structural view of the main core of the present invention;

Figure 7 is a schematic view showing the structure of a second small core of the present invention.

Wherein, the reference numerals in the figure correspond to: 1-core head, 2-main core, 3-first longitudinal core, 4-second longitudinal core, 5-third longitudinal core, 6-fourth longitudinal core Bone, 7-fifth longitudinal core, 8-six longitudinal core, 9-seventh longitudinal core, 10-first transverse core, 11-second transverse core, 12-third transverse core, 13-fourth transverse core, 14-first bump, 15-second bump, 16-third bump, 17-fourth bump, 18-fifth bump, 19-sixth bump, 20-seventh bump, 21-first mounting slot, 22-second mounting slot, 23-third mounting slot, 24-four mounting slot, 25-fifth mounting slot, 26-sixth mounting slot, 27 - seventh mounting slot, 28 - eighth mounting slot, 29 - first small core, 30 - second small core, 31 - third small core, 32 - ninth mounting slot.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Example:

Referring to Figures 1-7, the present invention provides a large-scale loader hydraulic valve body casting mold, including an upper shell type, a lower shell type, a sand core, and a slinging system;

The core comprises a core 1, a main core 2 and a small core. The core 1 has four frames, and both front and rear frames are provided with two legs. The main core 2 is horizontally disposed in the core 1. The core head 1 is for fixing and supporting the main core 2, and the main core 2 is composed of seven longitudinal core bones and four transverse core bones horizontally disposed in the same plane, and the seven longitudinal core bones are arranged in parallel from left to right. a first longitudinal core 3, a second longitudinal core 4, a third longitudinal core 5, a fourth longitudinal core 6, a fifth longitudinal core 7, a sixth longitudinal core 8, and a seventh longitudinal core 9, The four transverse core bones include a first transverse core 10, a second transverse core 11, a third transverse core 12 and a fourth transverse core 13 arranged in parallel from front to back;

The first longitudinal core 3 to the sixth longitudinal core 8 are connected in a grid shape to the four transverse cores, and the first transverse core 10 to the third transverse core 12 and the seventh longitudinal core 9 Connected, the fourth transverse core 13 is not connected to the seventh longitudinal core 9;

The first longitudinal core 3 to the sixth longitudinal core 8 are disposed in a region between the first lateral core 10 and the second lateral core 11 with a first bump 14 and a second for forming an oil groove. a bump 15 and a third bump 16 are disposed on the first longitudinal core 3 to the sixth longitudinal core 8 in a region between the third lateral core 12 and the fourth lateral core 13 for forming The fourth bump 17, the fifth bump 18 and the sixth bump 19 of the oil groove, the first longitudinal core 3 to the sixth longitudinal core 8 are located on the second lateral core 11 and the third transverse core 12 A seventh bump 20 for forming an oil groove is disposed between the two regions; the first bump 14 is provided with an upward first mounting groove 21, and the sixth protruding block 19 is provided with an upward second portion. The mounting groove 22 is provided with a third mounting groove 23 downwardly, and the fourth protruding block 17 is provided with a downward fourth mounting groove 24, and the seventh protruding block 20 is upper and lower. A fifth mounting groove 25 and a sixth mounting groove 26 are respectively disposed at two ends, and the sixth longitudinal core 8 is located on the first lateral core 10 and the fourth lateral core 13 a seventh mounting slot 27 and an eighth mounting slot 28 are respectively provided in the area;

The small core is three layers, from top to bottom: the first layer includes a first small core 29, the second layer includes six second small cores 30, and the third layer includes six third small cores 31. Each of the second small cores 30 is fixed to the main core 2 through the first mounting groove 21, the second mounting groove 22, and the fifth mounting groove 25, and each of the third small cores 31 passes through the third mounting groove 23 and the fourth mounting groove 24. And the sixth mounting groove 26 is fixed to the main core 2, and a ninth mounting groove 32 is disposed in the middle of the upper surface of each of the second small cores 30, and the first small core 29 passes through the seventh mounting groove 27 and the eighth mounting groove 28 The main core 2 is fixed, and the first small core 29 is fixed to the second small core 30 through the ninth mounting groove 32;

The rigging system comprises two heat-insulating risers and two runners, the heat-insulated riser has a diameter of 90 mm and a height of 120 mm, and the riser is filled with resin sand, and the runner is set at The left and right sides of the upper shell type and the lower shell type

Specifically, the arcuate faces on the first core 29, the six second cores 30, and the six third cores 31 are formed by a movable block and a core cylinder and molded at one time.

Specifically, the fifth mounting slot 25 and the sixth mounting slot 26 are circular slots, a first mounting slot 21, a second mounting slot 22, a third mounting slot 23, a fourth mounting slot 24, and a seventh mounting slot 27, The eighth mounting groove 28 and the ninth mounting groove 32 are square slots.

Specifically, the sand core is a high fluidity sand.

Specifically, the sand core assembly gap is controlled by the sand core bonding tooling.

Specifically, the main core 2 is made of a special core mold and integrally molded.

Accordingly, the present invention also provides a method for manufacturing a large loader hydraulic valve body casting, comprising the following steps:

S1: Inspect the special core mold for making the main core, and clean the dirt on the mold. Use a high-aluminum ceramic rod with a diameter of 10 mm as the seven longitudinal cores on the main core, and Al ₂ O on the high alumina ceramic rod. ₃ content is 40% -50%, using sand as high fluidity sand, specifically Jinying B570US model high fluidity sand, heating temperature 180 °C-190 °C, sanding pressure 0.5MPa-0.6MPa, sand shooting time 5s -7s, curing time 100s-120s;

The invention has the following beneficial effects:

1. The structure is reasonable and compact, the reliability is strong, and the assembly and casting are convenient;

2. Using a high-aluminum ceramic rod with a diameter of 10mm (40%--50% Al2O3 content) as the main channel core, controlling the straightness of the main valve hole casting blank is less than 0.8 mm;

6. The casting pass rate is greatly improved and the casting cost is reduced.

The above is only the preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, and thus equivalent changes made in the claims of the present invention are still within the scope of the present invention.

Claims

Large-sized loader hydraulic valve body casting mold, characterized in that it comprises an upper shell type, a lower shell type, a sand core and a slinging system;

Forming a cavity of a large loader hydraulic valve body with the sand core after the upper shell type and the lower shell type are clamped;

The sand core comprises a core (1), a main core (2) and a small core, the core (1) is a four-frame, and both front and rear frames are provided with two legs, and the main core (2) is horizontal Provided in the core head (1) for fixing the main core (2), the main core (2) consisting of seven longitudinal cores and four transverse cores horizontally disposed in the same plane Composition, the seven longitudinal core bones include a first longitudinal core (3), a second longitudinal core (4), a third longitudinal core (5), and a fourth longitudinal core (s) arranged in parallel from left to right ( 6) a fifth longitudinal core (7), a sixth longitudinal core (8) and a seventh longitudinal core (9), the four transverse cores comprising a first transverse core aligned in parallel from front to back ( 10), a second transverse core (11), a third transverse core (12) and a fourth transverse core (13);

The first longitudinal core (3) to the sixth longitudinal core (8) are connected to the four transverse cores in a grid shape, the first transverse core (10) to the third transverse core (12) Connected to a seventh longitudinal core (9) that is not connected to the seventh longitudinal core (9);

The first longitudinal core bone (3) to the sixth longitudinal core bone (8) are disposed in a region between the first transverse core (10) and the second transverse core (11) for forming an oil groove. a first bump (14), a second bump (15) and a third bump (16), the first longitudinal core (3) to the sixth longitudinal core (8) are located on the third transverse core a fourth bump (17), a fifth bump (18) and a sixth bump (19) for forming an oil groove are provided in a region between the (12) and the fourth lateral core (13), The seventh longitudinal core (3) to the sixth longitudinal core (8) are provided with a seventh for forming an oil groove on a region between the second lateral core (11) and the third transverse core (12). a bump (20); the first protrusion (14) is provided with an upward first mounting groove (21), and the sixth protrusion (19) is provided with an upward second mounting groove (22). The third protrusion (16) is provided with a downward third mounting groove (23), and the fourth protrusion (17) is provided with a downward fourth mounting groove (24), the seventh The upper and lower ends of the protrusion (20) are respectively provided with a fifth mounting groove (25) and a sixth mounting groove (26), and the sixth longitudinal core (8) is located on the first transverse core (10) and the first a seventh mounting groove (27) and an eighth mounting groove (28) are respectively disposed in the area on the four transverse cores (13);

The small core is three layers, from top to bottom: the first layer includes a first small core (29), The second layer comprises six second small cores (30), and the third layer comprises six third small cores (31), each of the second small cores (30) passing through the first mounting groove (21) and the second mounting groove ( 22) and the fifth mounting groove (25) is fixed to the main core (2), and each of the third small cores (31) passes through the third mounting groove (23), the fourth mounting groove (24), and the sixth mounting groove (26) ) is fixed to the main core (2), and a ninth mounting groove (32) is disposed in the middle of the upper surface of each of the second small cores (30), and the first small core (29) passes through the seventh mounting groove (27) and The eight mounting slots (28) are fixed to the main core (2), and the first small core (29) is fixed to the second small core (30) through the ninth mounting slot (32);

The rigging system comprises two heat-insulating risers and two runners, the heat-insulated riser has a diameter of 90 mm and a height of 120 mm, and the riser is filled with resin sand, and the runner is set at The left and right sides of the upper shell type and the lower shell type.
The large loader hydraulic valve body casting mold according to claim 1, wherein said first small core (29), six second small cores (30) and six third small cores (31) are The circular arc surface is made of a live block and a core cylinder and is formed at one time.
A large loader hydraulic valve body casting mold according to claim 1, wherein said fifth mounting groove (25) and said sixth mounting groove (26) are circular notches, said first mounting groove ( 21), a second mounting groove (22), a third mounting groove (23), a fourth mounting groove (24), a seventh mounting groove (27), an eighth mounting groove (28), and a ninth mounting groove (32) It is a square slot.
The large loader hydraulic valve body casting mold according to claim 1, wherein the sand core sand is high fluidity sand.
A large loader hydraulic valve body casting mold according to claim 1, wherein said seven longitudinal cores are each made of a high alumina ceramic rod having a diameter of 10 mm, said Al 2 of a high alumina ceramic rod The O 3 content is from 40% to 50%.
The large loader hydraulic valve body casting mold according to claim 1, wherein the sand core assembly gap is controlled by a sand core bonding tooling.
A large loader hydraulic valve body casting mold according to claim 1, wherein The main core (2) is made of a special core mold and integrally formed.
A method for manufacturing a hydraulic valve body casting of a large loader, characterized in that the method comprises the following steps:

S1: Inspect the special core mold for making the main core, and clean the dirt on the mold. Use a high-aluminum ceramic rod with a diameter of 10 mm as the seven longitudinal cores on the main core, and Al 2 O on the high alumina ceramic rod. 3 content is 40% -50%, using sand as high fluidity sand, heating temperature 180 °C-190 °C, sanding pressure 0.5MPa-0.6MPa, sanding time 5s-7s, curing time 100s-120s;

S2: using a common hydraulic press to make a small core made of a special core making machine, the arc concave surface on the first small core, the second small core and the third small core is made by a live block and a core cylinder and formed once;

S3: Repair all the blunts on the sand core, remove the transition nozzle, fix the main core through the sand core bonding tool, first assemble the bottommost third core to the main core, and after the adhesive is completely solidified, The assembled sand core is turned over and fixed by the sand core bonding tool. The second small core and the third small core are assembled to the main core, the assembly gap of the control sand core is less than 0.1 mm, and then the main core level is set at In the core, there should be no gap between the core and the core interface, and there should be no excess adhesive;

S4: The sand core is horizontally disposed in the upper shell type and the lower shell type, and the upper shell type, the lower shell type and the sand core are clamped to form a cavity of the hydraulic valve body, and the upper shell type and the lower shell type are embedded in the sand box. The cavity between the outer shell of the upper shell type and the lower shell type and the inner side of the sand box is covered with a sand layer, and the sand layer is provided with a pouring system connected with the shell type, and the pouring system adopts two heating and heat insulation risers and two The sprue, the heat-insulating riser has a diameter of 90 mm and a height of 120 mm, and the riser is filled with resin sand;

S5: pouring molten iron index, using a silicon germanium inoculant with a mass fraction of 0.3% and a silicon rare earth inoculant with a mass fraction of 0.2%, in the case of pouring, the molten iron is dispersed into the water through the thin gates on both sides of the upper and lower shells. The pouring temperature is 1380 ° C - 1420 ° C, the pouring time is 25 s-28 s, and the tapping temperature is 1520 ° C - 1540 ° C.