A special hydraulic valve body casting and its casting process

Abstract

The present invention relates to a special hydraulic valve body casting and a casting process thereof. The valve body casting is designed with a mold. A transverse flow channel, a vertical flow channel and a plurality of auxiliary flow channels are arranged in the valve body casting. The transverse flow channel is a main flow channel, and a first ring groove, a second ring groove, a third ring groove, a fourth ring groove, a fifth ring groove, a sixth ring groove, a seventh ring groove and an eighth ring groove are arranged on it from left to right. The left end of the transverse flow channel faces a flow channel opening on the left side of the valve body casting, and the right end faces a flow channel opening on the right side of the valve body casting. The vertical flow channel is located directly below the transverse flow channel and between the fourth ring groove and the fifth ring groove on the transverse flow channel. The first ring groove, the second ring groove and the third ring groove are arranged on the vertical flow channel from top to bottom. A casting process is specially designed according to the structure of the valve body casting to solve the problems of fracture of the inner cavity of the casting and water leakage from the riser, and the appearance of the casting is also very perfect.

Description

Technical Field

[0001] The present invention relates to the technical field of casting, in particular to a special hydraulic valve body casting and a casting process thereof. Background Art

[0002] Although my country is currently a major engineering machinery manufacturing country, its industry is large but not strong. There is overcapacity in low- and mid-range products, and high-end hydraulic components are almost entirely imported. The development of the hydraulic industry lags significantly behind that of the mainframe industry, becoming a major bottleneck restricting the development of the equipment manufacturing industry. Currently, the overall manufacturing technology level of my country's hydraulic components industry still lags significantly behind that of advanced countries. The valve body designed by Jiangyin Yibei Hydraulics Co., Ltd. is comparable in technology to similar products from advanced countries. The project's products demonstrate a high level of casting technology and are expected to develop positively. Hydraulic valves, as key components in hydraulic systems, offer advantages such as high integration, strong reliability, and long life. The development of these products will lay a solid foundation for improving the company's own high-end hydraulic valve body casting technology, meeting the needs of domestic high-end hydraulic valve users, and replacing imported valves. This project has significant practical significance for overcoming the poor precision and low technical content of similar domestic castings and for expanding market share both domestically and internationally. Summary of the Invention

[0003] The invention provides a special hydraulic valve body casting and a casting process thereof.

[0004] The technical solution of the present invention:

[0005] A special hydraulic valve body casting, which is designed in accordance with the shape and has six faces: front, back, left, right, top and bottom; the valve body casting is provided with three flow openings at the front, three flow openings at the back, one flow opening at the left, one flow opening at the right, two flow openings at the top and three flow openings at the bottom; the bottom of the valve body casting is a trapezoidal shape that is wide at the top and narrow at the bottom, and of the three flow openings provided thereon, one is located on the lower plane of the trapezoid and is the middle flow opening, and the other two are located on the two side faces of the trapezoid and are inclined, and are the side flow openings.

[0006] A horizontal flow channel, a vertical flow channel and several auxiliary flow channels are provided in the valve body casting. The horizontal flow channel is a main flow channel, and the first horizontal flow channel ring groove, the second horizontal flow channel ring groove, the third horizontal flow channel ring groove, the fourth horizontal flow channel ring groove, the fifth horizontal flow channel ring groove, the sixth horizontal flow channel ring groove, the seventh horizontal flow channel ring groove and the eighth horizontal flow channel ring groove are provided on it from left to right. The left end of the horizontal flow channel is opposite to and connected to a flow channel opening on the left side of the valve body casting, and the right end is opposite to and connected to a flow channel opening on the right side of the valve body casting. The vertical flow channel is located directly below the horizontal flow channel, between the fourth horizontal flow channel ring groove and the fifth horizontal flow channel ring groove on the horizontal flow channel. The first vertical flow channel ring groove, the second vertical flow channel ring groove and the third vertical flow channel ring groove are provided on the vertical flow channel from top to bottom; the upper end of the vertical flow channel is the first vertical flow channel ring groove above it, and the lower end is opposite to and connected to the middle flow channel opening on the bottom of the valve body casting.

[0007] The first annular groove of the transverse flow channel and the eighth annular groove of the transverse flow channel are symmetrical on the left and right. The upper ends of the first annular groove of the transverse flow channel and the eighth annular groove of the transverse flow channel are both provided with first sockets, and the lower ends are respectively connected to the first auxiliary flow channels.

[0008] The second annular groove of the transverse flow channel and the seventh annular groove of the transverse flow channel are symmetrical with each other, and the upper ends of the second annular groove of the transverse flow channel and the seventh annular groove of the transverse flow channel are respectively connected to the second auxiliary flow channel.

[0009] The third annular groove of the transverse flow channel and the sixth annular groove of the transverse flow channel are symmetrical with each other, and the lower ends of the third annular groove of the transverse flow channel and the sixth annular groove of the transverse flow channel are respectively connected to the third auxiliary flow channel.

[0010] The fourth annular groove of the transverse flow channel and the fifth annular groove of the transverse flow channel are symmetrical on the left and right. The lower end of the fourth annular groove of the transverse flow channel is connected to the fourth auxiliary flow channel, and the upper end of the fifth annular groove of the transverse flow channel is connected to the fifth auxiliary flow channel.

[0011] The two first auxiliary flow channels are symmetrical, and the front ends of the lower parts of the two first auxiliary flow channels are opposite to and connected to a flow channel opening on the front of the valve body casting, and the rear ends of the lower parts are opposite to and connected to a flow channel opening on the rear of the valve body.

[0012] The two second auxiliary flow channels are symmetrical with each other, and the upper ends of the two second auxiliary flow channels are directly opposite to and connected to a flow channel opening on the upper surface of the valve body casting.

[0013] The two third auxiliary flow channels are symmetrical, and the left end of the lower part of the left third auxiliary flow channel and the right end of the lower part of the right third auxiliary flow channel are both opposite to and connected to the side flow channel opening on the bottom of the valve body casting.

[0014] The front end of the upper portion of the fifth auxiliary flow channel faces and is connected to a flow channel opening on the front of the valve body casting, and the rear end of the upper portion is connected to a flow channel opening on the rear of the valve body casting.

[0015] The lower end of the fourth auxiliary flow channel is connected to the first annular groove of the vertical flow channel.

[0016] The left end and the right end of the second annular groove of the vertical flow channel are both provided with second recesses.

[0017] A third recess is provided on the left side of the upper portion of the left second auxiliary flow channel and on the right side of the upper portion of the right second auxiliary flow channel.

[0018] The parameters and specifications of the valve body casting are as follows:

[0019] 1) Material: QT500-7.

[0020] 2) Main tensile strength: ≥500.

[0021] 3) HB hardness: 190-230.

[0022] 4) No slag inclusion, air hole, shrinkage cavity, shrinkage porosity casting defects.

[0023] 5) Valve body weight: 11KG.

[0024] During the casting process of the above-mentioned valve body casting, it was found that due to the large casting area and small main hole of the casting, it was difficult to ensure that the inner cavity of the valve body casting was free of cracks. In addition, the internal flow channel of the casting was long, and the inner cavity was prone to fracture. At the same time, there was also the phenomenon of water spitting out from the riser. For this reason, we further improved the casting process. The casting process of the above-mentioned special hydraulic valve body casting adopts the resin sand shell mold process, and its steps are as follows: 1) core making; 2) molding; 3) smelting; 4) pouring.

[0025] Because the mud core of this product is complex and prone to core breakage, the flow channel in the mud core cavity cannot be kept without fracture. Therefore, after many casting tests, we found that bicycle wheel rim steel wire has the highest strength and strong bending resistance. Combined with high-strength HAGHD290 model mud core sand, the mud core strength is increased by combining the two, which can well ensure the qualified rate of cast castings. In step 1, we use bicycle wheel rim steel wire and high-strength HAGHD290 model mud core sand to make cores.

[0026] Due to the large and complex flow channels in the casting, the intensive heat during pouring can easily cause sintering. Therefore, the coating requirements for the mud core are also very important. After many tests, analyses and screenings, we finally adopted Shengshi Weiye's M590 coating, and the Baume degree of the coating was adjusted to 42°Bé-49°Bé. If the Baume degree is too high, it is very easy to form coating accumulation. If the Baume degree is too low, it will not play the role of coating. Therefore, after several tests, we set the Baume degree to 32°Bé-35°Bé, which is the most reasonable. It can effectively prevent sintering and ensure the surface quality of the flow channel. In step 1), we used Shengshi Weiye's M590 coating and adjusted the Baume degree of the coating to 42°Bé-49°Bé.

[0027] At the same time, in step 4), we disperse the water inlet to reduce the heat density of the molten iron and allow the gas in the molten iron to be discharged smoothly; thus solving the problems of fracture in the casting cavity and water leakage from the riser from the source.

[0028] We sectioned and dissected the valve body castings produced using this process and found no defects such as core breakage or pores. Other requirements also met the QT500-7 standard, and the castings also appeared to be flawless.

[0029] In step 1), a special hollow tube is used in conjunction with HAGHD290 core sand to make the core. The special hollow tube is a steel tube with holes arranged on it. This increases the core strength and facilitates exhaust.

[0030] The advantages of the present invention are reasonable design and ingenious conception. A valve body casting structure is designed, and a casting process is specially designed based on the valve body casting structure to solve the problems of fracture in the inner cavity of the casting and water leakage from the riser. At the same time, the appearance of the casting is also very perfect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a three-dimensional view of the valve body casting.

[0032] Figure 2 This is the main view of the valve body casting.

[0033] Figure 3 It is a side view of the valve body casting.

[0034] Figure 4 This is a top view of the valve body casting.

[0035] Figure 5 yes Figure 3 Schematic diagram of the cross section in the AA direction.

[0036] Figure 6 yes Figure 5 Schematic diagram of the cross section in the BB direction.

[0037] Figure 7yes Figure 5 Schematic diagram of the cross section in CC direction.

[0038] Figure 8 yes Figure 2 Schematic diagram of the cross section in the DD direction.

[0039] Figure 9 yes Figure 5 Schematic diagram of the cross section in the EE direction.

[0040] In the figure, there are valve body casting 1, transverse flow channel 1-1, vertical flow channel 1-2, first ring groove 1-3 of transverse flow channel, second ring groove 1-4 of transverse flow channel, third ring groove 1-5 of transverse flow channel, fourth ring groove 1-6 of transverse flow channel, fifth ring groove 1-7 of transverse flow channel, sixth ring groove 1-8 of transverse flow channel, seventh ring groove 1-9 of transverse flow channel, eighth ring groove 1-10 of transverse flow channel, first ring groove 1-11 of vertical flow channel, second ring groove 1-12 of vertical flow channel, third ring groove 1-13 of vertical flow channel, first nest 1-14, first auxiliary flow channel 1-15, second auxiliary flow channel 1-16, third auxiliary flow channel 1-17, fourth auxiliary flow channel 1-18, fifth auxiliary flow channel 1-19, second nest 1-20, third nest 1-21. DETAILED DESCRIPTION

[0041] like Figure 1-9As shown, a special hydraulic valve body casting, the valve body casting 1 is designed with a mold, which has six faces: front, back, left, right, top and bottom; the valve body casting 1 is provided with three flow openings in the front, three flow openings in the back, one flow opening on the left, one flow opening on the right, two flow openings on the top, and three flow openings on the bottom; the bottom of the valve body casting 1 is a trapezoidal shape with a wide top and a narrow bottom, and of the three flow openings provided thereon, one is located on the lower plane of the trapezoid and is the middle flow opening, and the other two are located on the two side surfaces of the trapezoid and are inclined, and are the side flow openings; a horizontal flow channel 1-1, a vertical flow channel 1-2 and several auxiliary flow channels are provided in the valve body casting 1, Channel 1-1 is the main channel, on which the first annular groove 1-3 of the transverse flow channel, the second annular groove 1-4 of the transverse flow channel, the third annular groove 1-5 of the transverse flow channel, the fourth annular groove 1-6 of the transverse flow channel, the fifth annular groove 1-7 of the transverse flow channel, the sixth annular groove 1-8 of the transverse flow channel, the seventh annular groove 1-9 of the transverse flow channel, and the eighth annular groove 1-10 of the transverse flow channel are arranged from left to right. The left end of the transverse flow channel 1-1 is directly opposite to and connected to a flow channel opening on the left side of the valve body casting 1, and the right end is directly opposite to and connected to a flow channel opening on the right side of the valve body casting 1. The vertical flow channel 1-2 is located directly below the transverse flow channel 1-11 and between the fourth annular groove 1-6 of the transverse flow channel and the fifth annular groove A1-7 of the transverse flow channel. The vertical flow channel 1-2 is arranged from top to bottom in sequence. A vertical flow channel is provided with a first annular groove 1-11, a second annular groove 1-12, and a third annular groove 1-13; the upper end of the vertical flow channel 1-2 is the first annular groove 1-11 of the vertical flow channel, and the lower end is directly opposite to and connected to the middle flow channel opening on the lower side of the valve body casting 1; the first annular groove 1-3 of the transverse flow channel is symmetrical with the eighth annular groove 1-10 of the transverse flow channel, and the upper ends of the first annular groove 1-3 of the transverse flow channel and the eighth annular groove 1-10 of the transverse flow channel are both provided with a first nest 1-14, and the lower ends are respectively connected to the first auxiliary flow channel 1-15; the second annular groove 1-4 of the transverse flow channel is symmetrical with the seventh annular groove 1-9 of the transverse flow channel, and the upper ends of the second annular groove 1-4 of the transverse flow channel and the seventh annular groove 1-9 of the transverse flow channel are respectively Connected to the second auxiliary flow channel 1-16; the third annular groove 1-5 of the transverse flow channel is symmetrical with the sixth annular groove 1-8 of the transverse flow channel, and the lower ends of the third annular groove 1-5 and the sixth annular groove 1-8 of the transverse flow channel are respectively connected to the third auxiliary flow channel 1-17; the fourth annular groove 1-6 of the transverse flow channel is symmetrical with the fifth annular groove 1-7 of the transverse flow channel, the lower end of the fourth annular groove 1-6 of the transverse flow channel is connected to the fourth auxiliary flow channel 1-18, and the upper end of the fifth annular groove 1-7 of the transverse flow channel is connected to the fifth auxiliary flow channel 1-19; the two first auxiliary flow channels 1-15 are symmetrical, and the lower front ends of the two first auxiliary flow channels 1-15 are both directly opposite to and connected to a flow channel opening on the front of the valve body casting 1, and the lower rear ends are both directly opposite to and connected to a flow channel opening on the rear of the valve body 1;The two second auxiliary flow channels 1-16 are symmetrical, and the upper ends of the two second auxiliary flow channels 1-16 are both facing and connected to a flow channel opening on the upper side of the valve body casting 1; the two third auxiliary flow channels 1-17 are symmetrical, and the lower left end of the left third auxiliary flow channel 1-17 and the lower right end of the right third auxiliary flow channel 1-17 are both facing and connected to the side flow channel opening on the lower side of the valve body casting 1; the upper front end of the fifth auxiliary flow channel 1-19 is facing and connected to a flow channel opening in front of the valve body casting 1, and the upper rear end is connected to a flow channel opening on the rear side of the valve body casting 1; the fourth auxiliary flow channel 1-18 The lower end is connected to the first annular groove 1-11 of the vertical flow channel; the left and right ends of the second annular groove 1-12 of the vertical flow channel are each provided with a second recess 1-20; the upper left portion of the left second auxiliary flow channel 1-16 and the upper right portion of the right second auxiliary flow channel 1-16 are each provided with a third recess 1-21. The parameters and specifications of the valve body casting 1 are as follows: 1) Material: QT500-7; 2) Body tensile strength: ≥500; 3) HB hardness: 190-230; 4) Free from slag inclusions, pores, shrinkage cavities, or shrinkage defects; 5) Valve body weight: 11 kg.

[0042] The casting process of the valve body casting 1 adopts a resin sand shell mold process, and its steps are as follows: 1) core making; 2) molding; 3) smelting; 4) pouring; in step 1), bicycle wheel rim steel wire is combined with high-strength HAGHD290 model mud core sand to make the core; Shengshi Weiye's M590 paint is used, and the Baume degree of the paint is adjusted to 42°Bé-49°Bé; in step 4), water is dispersed; in step 1), a special hollow tube is also used in combination with the HAGHD290 model mud core sand to make the core; the special hollow tube is a steel tube with holes arranged thereon.

[0043] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A special hydraulic valve body casting, the valve body casting is designed according to the mold, and has six faces: front, rear, left, right, top and bottom; characterized in that: The valve body casting is provided with three flow openings at the front, three flow openings at the back, one flow opening at the left, one flow opening at the right, two flow openings at the top, and three flow openings at the bottom; the bottom of the valve body casting is a trapezoidal shape that is wide at the top and narrow at the bottom. Among the three flow openings provided thereon, one is located on the lower plane of the trapezoid and is the middle flow opening, and the other two are respectively located on the two side surfaces of the trapezoid and are inclined and are the side flow openings; A transverse flow channel, a vertical flow channel and a plurality of auxiliary flow channels are arranged in the valve body casting. The transverse flow channel is a main flow channel, and the first transverse flow channel ring groove, the second transverse flow channel ring groove, the third transverse flow channel ring groove, the fourth transverse flow channel ring groove, the fifth transverse flow channel ring groove, the sixth transverse flow channel ring groove, the seventh transverse flow channel ring groove and the eighth transverse flow channel ring groove are arranged on it from left to right. The left end of the transverse flow channel faces and is connected to a flow channel opening on the left side of the valve body casting, and the right end faces and is connected to a flow channel opening on the right side of the valve body casting. The vertical flow channel is located directly below the transverse flow channel, between the fourth transverse flow channel ring groove and the fifth transverse flow channel ring groove on the transverse flow channel. The first vertical flow channel ring groove, the second vertical flow channel ring groove and the third vertical flow channel ring groove are arranged on the vertical flow channel from top to bottom; the upper end of the vertical flow channel is the first vertical flow channel ring groove on it, and the lower end faces and is connected to the middle flow channel opening on the bottom of the valve body casting; The first annular groove of the transverse flow channel and the eighth annular groove of the transverse flow channel are symmetrical with each other, and the first annular groove of the transverse flow channel and the eighth annular groove of the transverse flow channel are both provided with first recesses at their upper ends, and the lower ends are respectively connected to the first auxiliary flow channels; The second annular groove of the transverse flow channel and the seventh annular groove of the transverse flow channel are symmetrical with each other, and the upper ends of the second annular groove of the transverse flow channel and the seventh annular groove of the transverse flow channel are respectively connected to the second auxiliary flow channel; The third annular groove of the transverse flow channel and the sixth annular groove of the transverse flow channel are symmetrical with each other, and the lower ends of the third annular groove of the transverse flow channel and the sixth annular groove of the transverse flow channel are respectively connected to the third auxiliary flow channel; The fourth annular groove of the transverse flow channel and the fifth annular groove of the transverse flow channel are symmetrical with each other, the lower end of the fourth annular groove of the transverse flow channel on the transverse flow channel is connected to the fourth auxiliary flow channel, and the upper end of the fifth annular groove of the transverse flow channel on the transverse flow channel is connected to the fifth auxiliary flow channel; The two first auxiliary flow channels are symmetrical, the front ends of the lower parts of the two first auxiliary flow channels are directly facing and connected to a flow channel opening on the front of the valve body casting, and the rear ends of the lower parts are directly facing and connected to a flow channel opening on the rear of the valve body; The two second auxiliary flow channels are symmetrical, and the upper ends of the two second auxiliary flow channels are directly opposite to and connected to a flow channel opening on the upper surface of the valve body casting; The two third auxiliary flow channels are symmetrical, and the left end of the lower part of the left third auxiliary flow channel and the right end of the lower part of the right third auxiliary flow channel are both directly facing and connected to the side flow channel opening on the lower side of the valve body casting; The front end of the upper portion of the fifth auxiliary flow channel faces and is connected to a flow channel opening on the front of the valve body casting, and the rear end of the upper portion is connected to a flow channel opening on the rear of the valve body casting; The lower end of the fourth auxiliary flow channel is connected to the first annular groove of the vertical flow channel; The left and right ends of the second annular groove of the vertical flow channel are both provided with second recess grooves; A third recess is provided on the left side of the upper part of the left second auxiliary flow channel and on the right side of the upper part of the right second auxiliary flow channel; The two flow channel openings on the upper surface of the valve body casting are located between the second transverse flow channel annular groove and the seventh transverse flow channel annular groove on the transverse flow channel in the transverse direction.

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