Nozzle for cavitation treatment and cavitation treatment method

Abstract

The aim is to improve the efficiency of the cavitation treatment by CASF. 【Solution means】A nozzle 100 for cavitation treatment that is immersed in a treatment liquid 203 in which an abrasive 204 is turbid and injects a jet C1 of the treatment liquid 203 accompanied by cavitation, comprising: an injection part 10 having a nozzle 12 that injects the jet C1 along an injection axis 13; a liquid guiding part main body 20 arranged in the injection part 10 and covering the nozzle 12; a liquid chamber 30 arranged in the liquid guiding part main body 20 and facing the nozzle 12; a jet outlet 40 that extends along the injection axis 13 and penetrates from the liquid chamber 30 to the outside of the liquid guiding part main body 20; and a liquid guiding passage 50 that extends in a direction different from the injection axis 13 and penetrates from the liquid chamber 30 to the outside of the liquid guiding part main body 20.

Description

Technical Field

[0001] The present invention relates to a nozzle for cavitation treatment.

Background Art

[0002] There is known a cavitation surface treatment method called cavitation abrasive surface finishing (CASF) in which the surface roughness of an object is smoothed and peening is performed using a cavitation jet containing an abrasive (US2024 / 0001509A1).

Summary of the Invention

Problems to be Solved by the Invention

[0003] In CASF, the supply amount of the abrasive to the object affects the efficiency of the cavitation treatment. An object of the present invention is to improve the efficiency of the cavitation treatment by CASF.

Means for Solving the Problems

[0004] A first aspect of the present invention is a nozzle for cavitation treatment that is immersed in a treatment liquid in which an abrasive is turbid and jets the treatment liquid with cavitation towards the object injecting and smooth the surface of the object, and apply compressive residual stress to the surface of the object and has an injection part having a nozzle for injecting the jet along an injection axis, a liquid guiding part main body disposed in the injection part and covering the nozzle, a liquid chamber disposed in the liquid guiding part main body and facing the nozzle, a liquid guiding passage extending in a direction different from the injection axis and penetrating from the liquid chamber to the outside of the liquid guiding part main body and a jet outlet extending along the injection axis and penetrating from the liquid chamber to the outside of the liquid guiding part main body and the treatment liquid is caused to flow into the liquid chamber as an introduction flow from the outside of the liquid guiding portion main body and comprising and a jet outlet extending along the injection axis and penetrating from the liquid chamber to the outside of the liquid guiding part main body and the jet flow and the introduction flow are caused to flow out from the liquid chamber is a nozzle for cavitation treatment. is a nozzle for cavitation treatment.

[0005] A low-pressure area is formed in the liquid chamber by the injection of the jet flow, and the processing liquid flows into the liquid chamber from outside the main body of the liquid guiding part through the liquid guiding path and flows out together with the jet flow from the jet outlet.

[0006] The jet diameter of the injection part is, for example, 0.5 mm to 3 mm. The injection pressure of the jet flow is, for example, 10 MPa to 200 MPa.

[0007] The main body of the liquid guiding part is, for example, cylindrical or prismatic. At this time, the jet axis may coincide with the central axis of the main body of the liquid guiding part. The jet outlet may be formed at the center of the bottom surface of the main body of the liquid guiding part. The liquid guiding path may open on the side surface of the main body of the liquid guiding part. A plurality of liquid guiding paths may be arranged at equal intervals around the jet axis.

[0008] The main body of the liquid guiding part may be detachable from the injection part. A plurality of types of main bodies of the liquid guiding part with different shapes may be prepared, and the main body of the liquid guiding part may be appropriately replaced according to various conditions such as the material and shape of the object.

[0009] The abrasive is abrasive particles. The abrasive is, for example, ceramics, alumina, garnet, zirconia.

[0010] The object is made of metal. The metal constituting the object is, for example, a heat-resistant alloy, an aluminum alloy, a magnesium alloy, titanium, a titanium alloy, steel, or a corrosion-resistant steel. The object is, for example, a mechanical part, a medical device part, or a medical instrument. The mechanical part is, for example, a pipe, a valve, a pipe joint, or an aerospace part. The medical instrument includes a surgical implant. The aerospace parts include aircraft engine parts and other aircraft parts, rocket engine parts, spacecraft parts, artificial satellite parts, and rocket pipes.

[0011] Both the object and the cavitation treatment nozzle are immersed in the processing liquid stored in the tank. In the processing liquid, a jet flow of the processing liquid is injected from the cavitation treatment nozzle toward the object. The processing liquid is, for example, water. The processing liquid may contain a rust inhibitor.

[0012] Cavitation treatment is performed on part or all of the surface of the object.

Advantages of the Invention

[0013] According to the present invention, the efficiency of cavitation treatment by CASF can be improved.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0015] As shown in FIGS. 1 to 4, the nozzle 100 for cavitation treatment of the embodiment includes an injection part 10, a liquid guiding part main body 20, a liquid chamber 30, a jet outlet 40, a liquid guiding path 50, and a fixing part 60. FIG. 2 is a cross-sectional view taken along line II-II of FIG. 3. The nozzle 100 for cavitation treatment injects a jet flow C1 in the left direction in FIGS. 1 and 2. In the nozzle 100 for cavitation treatment, the downstream side of the jet flow C1 is the tip side (the left side in FIGS. 1 and 2), and the upstream side is the base end side (the right side in FIGS. 1 and 2).

[0016] The injection part 10 includes a shaft body 11 and a nozzle opening 12. The shaft body 11 has a cylindrical shape. The shaft body 11 extends along the central axis 101. The nozzle opening 12 is provided at the tip of the shaft body 11. The nozzle opening 12 injects the jet flow C1 along the injection axis 13. The injection axis 13 coincides with the central axis 101. A high-pressure fluid supply source (not shown) described later is connected to the base end side of the shaft body 11.

[0017] The liquid guiding part main body 20 is cylindrical. The liquid guiding part main body 20 extends along the central axis 101. The liquid guiding part main body 20 has a liquid guiding part tip end face 21, a liquid guiding part base end face 22, a liquid guiding part side face 23, and an insertion hole 24. The liquid guiding part tip end face 21 and the liquid guiding part base end face 22 are circular. The liquid guiding part main body 20 is separate from the injection part 10. The insertion hole 24 extends from the center of the liquid guiding part base end face 22 along the central axis 101 toward the tip side and reaches the inside of the liquid guiding part main body 20. The insertion hole 24 has a circular cross section. The shaft body 11 is inserted into the insertion hole 24. Thereby, the liquid guiding part main body 20 is arranged on the injection part 10 and covers the nozzle 12. The injection part 10 is inserted up to the front side (base end side) from the innermost part of the insertion hole 24. That is, a space is formed between the tip of the injection part 10 and the tip of the insertion hole 24.

[0018] The liquid chamber 30 is arranged inside the liquid guiding part main body 20. The liquid chamber 30 is a cylindrical space. The liquid chamber 30 has a liquid chamber tip end face 31 and a liquid chamber side face 32. The base end side of the liquid chamber 30 is blocked by the injection part 10. Therefore, the nozzle 12 faces the base end side of the liquid chamber 30. The liquid chamber 30 is a part of the insertion hole 24 and is the part between the tip of the injection part 10 and the tip of the insertion hole 24.

[0019] The jet outlet 40 is a hole that penetrates from the liquid chamber 30 to the outside of the liquid guiding part main body 20. The jet outlet 40 extends along the jet axis 13. The jet outlet 40 opens at the center of the liquid chamber tip end face 31 and the center of the liquid guiding part tip end face 21, respectively. The jet outlet 40 has a circular cross section. The central axis of the jet outlet 40 coincides with the jet axis 13. The diameter of the jet outlet 40 is smaller than the diameter of the liquid chamber 30.

[0020] The liquid guiding passage 50 is a hole that penetrates from the liquid chamber 30 to the outside of the liquid guiding part main body 20. The liquid guiding passage 50 extends in a direction different from the injection axis 13. The liquid guiding passage 50 has a liquid guiding axis 51 that is a straight line intersecting the injection axis 13. The liquid guiding passage 50 extends along the liquid guiding axis 51. When viewed from the direction of the central axis 101, the liquid guiding axis 51 extends in the radial direction of the liquid guiding part main body 20. The liquid guiding passage 50 opens to the liquid chamber side surface 32 and the liquid guiding part side surface 23 respectively. The liquid guiding passage 50 is directed toward the tip side as it goes toward the liquid chamber 30 side. The angle α formed by the injection axis 13 and the liquid guiding axis 51 is, for example, 20 degrees. The liquid guiding passage 50 has a circular cross-section. The central axis of the liquid guiding passage 50 coincides with the liquid guiding axis 51. The diameter of the liquid guiding passage 50 is smaller than the diameter of the liquid chamber 30. As shown in FIG. 3, six liquid guiding passages 50 are provided. Each liquid guiding passage 50 is arranged at equal intervals around the injection axis 13. Note that the liquid guiding axis 51 may be a curve.

[0021] As shown in FIG. 4, the fixing part 60 has a split groove 61 and a fastening bolt 62. The split groove 61 is formed along the diameter direction on the base end surface 22 of the liquid guiding part. The fastening bolt 62 is inserted from the liquid guiding part side surface 23 so as to intersect the split groove 61. By tightening the fastening bolt 62 with the injection part 10 inserted into the insertion hole 24, the interval of the split groove 61 becomes narrower, and the liquid guiding part main body 20 is fixed to the injection part 10.

[0022] A cavitation treatment device 200 to which a cavitation treatment nozzle 100 is attached will be described. As shown in FIG. 5, the cavitation treatment device 200 has a tank 201, a cavitation treatment nozzle 100, a fixing base 202, and a high-pressure fluid supply source (not shown).

[0023] The tank 201 stores a treatment liquid 203. The treatment liquid 203 is, for example, water. The treatment liquid 203 is a mixture in which an abrasive 204 is turbid. The tank 201 may have a device for circulating the stored treatment liquid 203.

[0024] The nozzle 100 for cavitation treatment is connected to a high-pressure fluid supply source. The nozzle 12 is vertically downward. The nozzle 100 for cavitation treatment can move in three axial directions: the horizontal direction (front-back direction and left-right direction) and the vertical direction. The injection speed (pressure) of the jet C1 and the movement of the nozzle 100 for cavitation treatment in the three axial directions are controlled by a control device (not shown).

[0025] The fixing table 202 fixes the workpiece (object) 300. The workpiece 300 is fixed to the fixing table 202 with fasteners (not shown) such as bolts and clamps. The fixing table 202 can move in the vertical direction. The workpiece 300 is taken in and out of the tank 201 by the vertical movement of the fixing table 202. The vertical movement of the fixing table 202 is controlled by a control device (not shown).

[0026] The nozzle 100 for cavitation treatment and the workpiece 300 fixed to the fixing table 202 are immersed in the treatment liquid 203 in which the abrasive 204 is turbid. The high-pressure fluid supply source is activated to inject the jet C1 along the injection axis 13 from the nozzle 12 of the nozzle 100 for cavitation treatment. The injection direction of the jet C1 is vertically downward. The jet C1 is a linear rod-shaped jet. The jet C1 contains many cavities. With this cavitation treatment device 200, the jet C1 can be injected at an arbitrary distance from an arbitrary location of the workpiece 300.

[0027] When the high-pressure treatment liquid 203 is injected at high speed as the jet C1 from the nozzle 12, a low-pressure part is formed in the liquid chamber 30. The pressure of the low-pressure part is lower than the pressure of the treatment liquid 203 around the nozzle 100 for cavitation treatment. Therefore, the treatment liquid 203 flows into the liquid chamber 30 as the introduction flow C2 from the outside of the liquid guide part main body 20 through the liquid guide path 50. Then, the introduction flow C2 flows out from the jet outlet 40 together with the jet C1.

[0028] The jet flow C1 entrains the abrasive 204 and impinges on the surface of the workpiece 300. The unnecessary part of the workpiece 300 is removed by the abrasive 204 contained in the jet flow C1. After the unnecessary part is removed, the surface of the workpiece 300 is smoothed by the abrasive 204 contained in the jet flow C1. By adding the introduction flow C2 to the jet flow C1, more abrasive 204 is entrained, so the efficiency of the cavitation treatment by CASF is improved. When the cavity contained in the jet flow C1 collapses, the surface of the workpiece 300 is peened by the impact force. By the peening treatment, compressive residual stress is imparted to the surface of the workpiece 300. While jetting the jet flow C1, the cavitation treatment nozzle 100 may be moved along the shape of the workpiece 300.

[0029] The liquid guiding part main body 20 is detachable from the injection part 10. A plurality of types of liquid guiding part main bodies 20 having different shapes may be prepared and the liquid guiding part main body 20 may be appropriately replaced. The different parts of the shape of the liquid guiding part main body 20 are, for example, the diameter, number, and angle with respect to the injection axis 13 of the liquid guiding path 50. For example, the shape and size of the liquid chamber 30. For example, the diameter of the jet outlet 40. If the shape of the liquid guiding part main body 20 is different, the mode of the introduction flow C2 is also different. By selecting an appropriate liquid guiding part main body 20 according to various conditions such as the material and shape of the workpiece 300, an appropriate cavitation treatment can be performed.

[0030] The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the present invention. All technical matters included in the technical idea described in the claims are the subject of the present invention. The above embodiments show preferred examples, but those skilled in the art can realize various alternative examples, modification examples, deformation examples, or improvement examples from the content disclosed in this specification, and these are included in the technical scope described in the appended claims.

Explanation of Reference Numerals

[0031] 10 Injection part 12 Nozzle 13 Injection axis 20 Liquid guiding part main body 30 Liquid chamber 40 Jet outlet 50 Liquid guide path 100 Nozzle for cavitation treatment 203 Treatment liquid 204 Abrasive C1 Jet

Claims

1. A nozzle for cavitation treatment that is immersed in a treatment liquid in which abrasive is turbid, injects a jet of the treatment liquid with cavitation toward an object, smoothes the surface of the object, and imparts compressive residual stress to the surface of the object, comprising: An injection part having a nozzle for injecting the jet along an injection axis; A liquid guide part body disposed on the injection part and covering the nozzle; A liquid chamber disposed in the liquid guide part body and facing the nozzle; A liquid guide path that extends in a direction different from the injection axis, penetrates from the liquid chamber to the outside of the liquid guide part body, and allows the treatment liquid to flow into the liquid chamber as an introduction flow from the outside of the liquid guide part body; A jet outlet that extends along the injection axis, penetrates from the liquid chamber to the outside of the liquid guide part body, and allows the jet and the introduction flow to flow out from the liquid chamber. A nozzle for cavitation treatment.

2. The liquid guide path has a liquid guide axis that is a straight line intersecting the injection axis. The nozzle for cavitation treatment according to Claim 1.

3. The liquid guide path faces the downstream side of the jet as it goes toward the liquid chamber side. The nozzle for cavitation treatment according to Claim 1 or 2.

4. Having a plurality of the liquid guide paths. The nozzle for cavitation treatment according to Claim 1 or 2.

5. The liquid guide part body is separate from the injection part. The nozzle for cavitation treatment according to Claim 1 or 2.

6. A cavitation treatment method using a nozzle for cavitation treatment that injects a jet with cavitation, wherein the nozzle for cavitation treatment has an injection part having a nozzle for injecting the jet along an injection axis; a liquid guide part body disposed on the injection part and covering the nozzle; a liquid chamber disposed in the liquid guide part body and facing the nozzle; a jet outlet that extends along the injection axis and penetrates from the liquid chamber to the outside of the liquid guide part body; a liquid guide path that extends in a direction different from the injection axis and penetrates from the liquid chamber to the outside of the liquid guide part body, and immersing the nozzle for cavitation treatment and the object in a treatment liquid in which abrasive is turbid; injecting the jet of the treatment liquid from the nozzle; allowing the treatment liquid to flow into the liquid chamber as an introduction flow from the outside of the liquid guide part body through the liquid guide path, and allowing the introduction flow to flow out from the jet outlet together with the jet. A cavitation treatment method, wherein the jet is made to collide with the object by causing the jet to entrain the abrasive contained in the introduction flow in addition to the abrasive contained in the jet. Cavitation treatment method.

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