阅读说明：本技术 防治穴蚀的船用柴油机球铁机体及其制作方法 (Marine diesel engine ductile iron body for preventing cavitation erosion and manufacturing method thereof ) 是由 黄猛 辛强之 赵国栋 刘毅 张新亮 王俊 穆振仟 赵文凯 贾宝富 桑伟 荆涛 于 2021-08-04 设计创作，主要内容包括：本发明涉及防治穴蚀的船用柴油机球铁机体及其制作方法,包括机体,所述的机体上设有若干个缸套冷却水腔,机体顶面位于缸套冷却水腔外围设有若干个出水孔。所述的缸套冷却水腔包括下部环形水槽以及上部环形水槽,下部环形水槽与上部环形水槽通过上水腔贯通连接。所述的下部环形水槽直径大于上部环形水槽直径。所述的的上部环形水槽通过连接孔与出水孔贯通连接。防治穴蚀的船用柴油机球铁机体采用铸造方法整体成型。铸造时,缸套冷却水腔位置处采用呋喃树脂砂造芯。本发明通过优化机体缸套端环形水槽结构以及将机械加工去料改为直接铸造的方法来防治穴蚀缺陷。(The invention relates to a ductile iron engine body of a marine diesel engine for preventing cavitation erosion and a manufacturing method thereof. The cylinder sleeve cooling water cavity comprises a lower annular water tank and an upper annular water tank, and the lower annular water tank is communicated with the upper annular water tank through the water feeding cavity. The diameter of the lower annular water tank is larger than that of the upper annular water tank. The upper annular water tank is communicated with the water outlet hole through a connecting hole. The ductile iron body of the marine diesel engine for preventing cavitation corrosion is integrally formed by adopting a casting method. During casting, the position of the cooling water cavity of the cylinder sleeve is cored by furan resin sand. The invention prevents and treats the cavitation corrosion defect by optimizing the annular water tank structure at the cylinder sleeve end of the engine body and changing the mechanical processing and material removal into the direct casting method.)

1. Marine diesel engine ductile iron organism of prevention and cure cavitation erosion, including organism (1), organism (1) on be equipped with a plurality of cylinder liner cooling water chamber (2), organism (1) top surface is located cylinder liner cooling water chamber (2) periphery and is equipped with a plurality of apopore (3), its characterized in that:

the cylinder sleeve cooling water cavity (2) comprises a lower annular water tank (201) and an upper annular water tank (202), the lower annular water tank (201) is communicated with the upper annular water tank (202) through an upper water cavity (203),

the diameter of the lower annular water tank (201) is larger than that of the upper annular water tank (202),

the upper annular water tank (202) is communicated with the water outlet hole (3) through a connecting hole (301).

2. The marine diesel ductile iron body for controlling cavitation according to claim 1, characterized in that:

the upper end of the cylinder sleeve cooling water cavity (2) is provided with an outlet channel, the upper annular water tank (202) is positioned below the outlet channel, and the diameter of the outlet channel is smaller than that of the upper annular water tank (202).

3. The marine diesel ductile iron body for pitting corrosion control according to claim 2, wherein:

the water outlet holes (3) are obliquely arranged, the water outlet holes (3) are simultaneously communicated and connected with the upper annular water tank (202) and the outlet channel,

the joint of the water outlet hole (3) and the outlet channel is 2-5 mm higher than the top surface of the upper annular water tank (202).

4. The marine diesel ductile iron body for pitting corrosion control according to claim 3, wherein:

the included angle between the axis of the water outlet hole (3) and the horizontal plane is 0-15 degrees.

5. The marine diesel ductile iron body for controlling cavitation according to claim 2, 3 or 4, characterized in that:

and arc chamfers are arranged on the top surface edge of the upper annular water tank (202) and the top surface edge of the lower annular water tank (201).

6. The marine diesel ductile iron body for controlling cavitation according to claim 1 or 2 or 3 or 4, characterized in that:

2-4 water feeding cavities (203) are distributed in an annular array around the axis of the cylinder sleeve cooling water cavity (2), the diameter of each water feeding cavity (203) is smaller than that of the upper annular water tank (202),

the radian of the water feeding cavity (203) is 60-90 degrees.

7. The marine diesel ductile iron body for pitting corrosion control according to claim 6, wherein:

the radial distance between the inner wall of the water feeding cavity (203) and the outer wall of the cylinder sleeve (4) is e, the distance between the inner wall of the upper annular water tank (202) and the outer wall of the cylinder sleeve (4) is d, and e is 1/4 d-1/2 d.

8. The marine diesel ductile iron body for controlling cavitation according to claim 7, characterized in that:

a bottom annular water tank (204) is connected below the lower annular water tank (201) in a penetrating way, the diameter of the bottom annular water tank (204) is larger than that of the lower annular water tank (201),

the bottom annular water tank (204) is connected with the lower annular water tank (201) to form an arc-shaped curved surface.

9. The manufacturing method of the ductile iron body of the marine diesel engine for preventing cavitation erosion adopts a casting method to integrally form, and is characterized in that:

during casting, the position of the cylinder sleeve cooling water cavity (2) adopts furan resin sand for core making.

10. The method for manufacturing a ductile iron body of a marine diesel engine for preventing cavitation corrosion according to claim 9, wherein the method comprises the following steps:

and quartz sand paint is coated on the surface of the furan resin sand core.

Technical Field

The invention belongs to the technical field of diesel engine body manufacturing, and particularly relates to a ductile iron body of a marine diesel engine for preventing cavitation erosion and a manufacturing method thereof.

Background

Through the analysis of cavitation corrosion organisms, the organisms find that electrochemical corrosion and erosion caused by high-flow-rate high-temperature circulating water are easy to occur on the metal surface formed by removing materials through mechanical processing in the environment of cooling water containing salt or high-impurity water solution. When the diesel engine works at high strength, the water temperature of the water flow of the annular water tank at the cylinder sleeve end of the engine body is increased, electrochemical corrosion and erosion can occur in the environment of salt-containing or high-impurity water solution of cooling water, and once the spherical graphite of the nodular cast iron is isolated, the spherical graphite is easy to fall off and aggravates the cavitation erosion of the material. In order to meet the high strength requirement of a high-performance diesel engine, a nodular cast iron material is required, so that the problem of corrosion resistance of a nodular cast iron engine body material is necessary.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the invention overcomes the defects of the prior art and provides a ductile iron engine body of a marine diesel engine for preventing cavitation corrosion and a manufacturing method thereof.

The technical scheme adopted by the invention for solving the problems in the prior art is as follows:

the ductile iron body of the marine diesel engine for preventing and treating the cavitation corrosion comprises an engine body, wherein a plurality of cylinder sleeve cooling water cavities are arranged on the engine body, and a plurality of water outlet holes are formed in the periphery of the cylinder sleeve cooling water cavities on the top surface of the engine body.

The cylinder sleeve cooling water cavity comprises a lower annular water tank and an upper annular water tank, and the lower annular water tank is communicated with the upper annular water tank through the water feeding cavity.

The diameter of the lower annular water tank is larger than that of the upper annular water tank.

The upper annular water tank is communicated with the water outlet hole through a connecting hole.

Preferably, the upper end of the cylinder sleeve cooling water cavity is provided with an outlet channel, the upper annular water tank is positioned below the outlet channel, and the diameter of the outlet channel is smaller than that of the upper annular water tank.

Preferably, the water outlet holes are obliquely arranged, and the water outlet holes are simultaneously communicated with the upper annular water tank and the outlet channel.

The joint of the water outlet hole and the outlet channel is 2-5 mm higher than the top surface of the upper annular water tank.

Preferably, the included angle between the axis of the water outlet hole and the horizontal plane is 0-15 degrees.

Preferably, the top surface edge of the upper annular water tank and the top surface edge of the lower annular water tank are both provided with arc chamfers.

Preferably, 2-4 water feeding cavities are distributed in an annular array around the axis of the cylinder sleeve cooling water cavity.

Preferably, the diameter of the upper water cavity is smaller than that of the upper annular water tank, and the radian of the upper water cavity is 60-90 degrees.

Preferably, the radial distance between the inner wall of the water feeding cavity and the outer wall of the cylinder sleeve is e, the distance between the inner wall of the upper annular water tank and the outer wall of the cylinder sleeve is d, and e is 1/4 d-1/2 d.

Preferably, a bottom annular water tank is connected below the lower annular water tank in a through mode, and the diameter of the bottom annular water tank is larger than that of the lower annular water tank.

The bottom annular water tank and the lower annular water tank are connected into an arc-shaped curved surface.

The method for manufacturing the ductile iron body of the marine diesel engine for preventing and treating cavitation erosion adopts a casting method to integrally form. During casting, the position of the cooling water cavity of the cylinder sleeve is cored by furan resin sand.

Preferably, the surface of the furan resin sand core is coated with a quartz sand coating.

Compared with the prior art, the invention has the following beneficial effects:

(1) through carrying out optimal design to cylinder liner cooling water cavity for the inside rivers of water cavity are more steady, are difficult for wrapping up in the gas. When the diesel engine works, the cooling water is not easy to be blown out to generate erosion.

(2) The apopore slope is arranged, and is higher than upper portion annular water cavity, and even there is a small amount of gas in the water cavity inside, also discharge from upper portion annular basin, apopore easily.

(3) The cylinder sleeve cooling water cavity changes the original method of mechanical processing and material removal into direct casting molding, and a dense layer of a strong oxidation layer of a casting surface is utilized to resist cavitation erosion.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a top view of a ductile iron engine for a marine diesel engine according to the present invention,

figure 2 is a cross-sectional view taken along plane a-a of the present invention,

FIG. 3 is a cross-sectional view taken along plane B-B of the present invention.

In the figure: 1-machine body, 2-cylinder sleeve cooling water cavity, 201-lower annular water tank, 202-upper annular water tank, 203-upper water cavity, 204-bottom annular water tank, 3-water outlet, 301-connecting hole and 4-cylinder sleeve.

Detailed Description

The attached drawings are the best embodiments of the ductile iron body of the marine diesel engine for preventing and controlling cavitation erosion and the manufacturing method thereof, and the invention is further described in detail with reference to the attached drawings.

Shown by attached figure 1 to attached figure 3, marine diesel engine ductile iron organism of prevention and cure cavitation erosion, including organism 1, organism 1 on be equipped with a plurality of cylinder liner cooling water chamber 2, 1 top surface of organism is located 2 peripheries in cylinder liner cooling water chamber and is equipped with a plurality of apopore 3, 4 apopores 3 are the annular array around 2 axes in cylinder liner cooling water chamber and distribute in this embodiment.

The cylinder sleeve cooling water cavity 2 is sequentially provided with an outlet channel, an upper annular water tank 202, an upper water cavity 203, a lower annular water tank 201 and a bottom annular water tank 204 which are communicated with each other from top to bottom.

The inner diameter of the outlet passage is the same as the outer diameter of the cylinder liner 4, and the diameter of the upper annular water tank 202 is larger than that of the outlet passage. The diameter of the upper annular water tank 202 is larger than that of the upper water cavity 203 and smaller than that of the lower annular water tank 201.

The 2 ~ 4 water feeding cavities 203 are distributed in an annular array around the axis of the cylinder sleeve cooling water cavity 2, and the radian of the water feeding cavities 203 is 60 ~ 90 deg. In this embodiment, two upper water cavities 203 are provided between the upper annular water tank 202 and the lower annular water tank 201.

The radial distance between the inner wall of the water feeding cavity 203 and the outer wall of the cylinder sleeve 4 is e, the distance between the inner wall of the upper annular water tank 202 and the outer wall of the cylinder sleeve 4 is d, and e is 1/4 d-1/2 d.

A bottom annular water tank 204 is connected below the lower annular water tank 201 in a through mode, and the diameter of the bottom annular water tank 204 is larger than that of the lower annular water tank 201.

In order to make the water flow more stable, the top surface edge of the upper annular water tank 202 and the top surface edge of the lower annular water tank 201 are both provided with arc chamfers, and the bottom annular water tank 204 and the lower annular water tank 201 are jointed into an arc curved surface.

The upper annular water tank 202 is connected with the water outlet hole 3 through a connecting hole 301. The water outlet holes 3 are obliquely arranged, and the included angle between the axis of the water outlet holes 3 and the horizontal plane is 0-15 degrees. Apopore 3 and upper portion annular basin 202 and exit channel link up simultaneously and are connected, and apopore 3 is higher than the distance on upper portion annular basin 202 top surface with the exit channel junction and is a, and an equals 2 ~ 5 mm.

The manufacturing method of the ductile iron body of the marine diesel engine for preventing and treating the cavitation erosion adopts a casting method to integrally form, belongs to the prior art, and is different from the prior art in that a furan resin sand core is adopted at the position of a cooling water cavity 2 of a cylinder sleeve during casting, and quartz sand paint is coated on the surface of the furan resin sand core. The cavitation erosion is resisted by utilizing the dense layer of the strong oxidation layer of the casting surface skin, and the cavitation erosion resisted by the dense layer of the strong oxidation layer of the casting surface skin has the following process characteristics: 1. the casting surface contains a SiO2 protective film due to powder metallurgy generated by sintering with quartz sand, and the film has high resistivity and high electrochemical stability and is not easy to generate electrochemical reaction; 2. the graphite tissue of the nodular cast surface is generally vermicular or flake graphite, and is relatively in accordance with the characteristic that the dynamic water flow graphite is not easy to fall off; 3. the surface layer has the characteristic of chilling, is compact in material and high in hardness, and can better resist erosion.

The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.