WO2022118988A1

WO2022118988A1 - Piston ring

Info

Publication number: WO2022118988A1
Application number: PCT/JP2021/044800
Authority: WO
Inventors: 慶吾亀山; 修平大野; 雄一石田; 孝宏森田; 大樹村山
Original assignee: 株式会社三井Ｅ＆Ｓマシナリー
Priority date: 2020-12-04
Filing date: 2021-12-06
Publication date: 2022-06-09
Also published as: JPWO2022118988A1

Abstract

The purpose of the present invention is to provide a piston ring that has, on an outer circumferential surface of a base material thereof, a wear-resistant layer formed of a wear-resistant material and that allows the wear status of the wear-resistant layer to be easily determined from the external appearance thereof. This piston ring has a sliding surface 3 including a laminate of a wear-resistant layer 2a of a wear-resistant material and an affinity layer 2b that are formed flush with each other on an outer circumferential surface of a base material 1. The outer circumferential surface of the base material 1 is provided with a wear determination member 4 formed of a different material from the base material 1. Preferably, an outermost portion of the wear determination member 4 is flush with the sliding surface 3.

Description

piston ring

The present invention relates to a piston ring, and more particularly to a piston ring in which a wear-resistant layer made of a wear-resistant material is formed on the outer peripheral surface of a base material, and it is easy to determine the wear state of the wear-resistant layer from the appearance. ..

The piston ring of an internal combustion engine such as a diesel engine (for example, a 2-stroke diesel main engine for ships) has a sliding surface on its outer circumference that slides on a cylinder liner and wears.

As described in Patent Document 1, a sliding surface having a wear-resistant layer made of ceramics, metal, or the like formed on the sliding surface has become the mainstream in recent years for the purpose of improving wear resistance.

Japanese Unexamined Patent Publication No. 3-125077

As mentioned above, most piston rings in recent years have a wear-resistant layer formed on the outer peripheral surface of the base metal. The wear-resistant layer has an outer peripheral surface that serves as a sliding surface to the cylinder liner. A wear-resistant material such as a cermet (Ceramics Metal) layer is used, and the outer layer is made of metal or the like. In some cases, a familiar layer (familiar layer) is used.

Since the wear-resistant layer made of a cermet layer has little difference in color and surface shape from the base material, it is difficult to understand the wear state (wear) of the wear-resistant layer from the appearance, and there is a risk that the base material will be worn. be.

In particular, the piston ring is visually inspected while being incorporated in the diesel engine in the engine room of the ship, which is not sufficiently bright, and it is the crew of the ship who conducts the visual inspection of the piston ring. Since he is not an expert in manufacturing, it is difficult to confirm the wear state of the sliding surface from the appearance.

The present invention has been made in view of such conventional circumstances, and a wear-resistant layer made of a wear-resistant material is formed on the outer peripheral surface of the base material, and the wear state of the wear-resistant layer can be determined from the appearance. It is an object of the present invention to provide an easy piston ring.

Other problems of the present invention will be clarified by the following description.

The above problems are solved by the following inventions.

[Invention of a piston ring in which a wear-resistant layer and a familiar layer (two layers) are formed]
1. 1.
A wear-resistant layer of a wear-resistant material is formed on the outer periphery of the base material, and a familiar layer is laminated on the outer layer of the wear-resistant layer to have a sliding surface formed flush with each other.
A piston ring provided with a wear identification material made of a member different from the base material on the outer peripheral surface of the base material.
2. 2.
The piston ring according to 1 above, wherein the wear identification material has a top flush with the sliding surface.
3. 3.
The piston ring according to 1 above, wherein the wear identification material has a top covered with the familiar layer.
4.
The piston ring according to any one of 1 to 3 above, wherein a wear identification material made of a member different from the wear resistant layer and the familiar layer is embedded in the wear resistant layer and / or the familiar layer.
5.
The piston ring according to any one of 1 to 4, wherein the wear identification material has a shape representing a character or a figure when viewed from the outer peripheral side of the sliding surface.
6.
A wear-resistant layer of a wear-resistant material is formed on the outer periphery of the base material, and a familiar layer is laminated on the outer layer of the wear-resistant layer to have a sliding surface formed flush with each other.
A piston ring provided with a wear identification recess on the outer peripheral surface of the base material.
7.
The piston ring according to 6 above, wherein a wear identification material made of a member different from the base material is fitted in the wear identification recess.
8.
6. The piston ring according to 6 or 7, wherein the wear identification recess is covered with the wear resistant layer and / or the familiar layer.
9.
The piston ring according to any one of 6 to 8, wherein the wear identification recess has a shape representing a character or a figure when viewed from the outer peripheral side of the sliding surface.
10.
The piston ring according to any one of 6 to 9, wherein a wear-resistant layer and / or a wear-identifying material made of a member different from the wear-resistant layer and the familiar layer is embedded in the wear-resistant layer and / or the familiar layer.

[Invention of a piston ring in which only a wear-resistant layer (single layer) is formed]
11.
A piston ring made of a ring-shaped base material.
A wear identification recess is provided on the outer peripheral portion of the base material.
A piston ring in which the outer peripheral surface of the base material is covered with a wear-resistant layer of a wear-resistant material, and the surface of the wear-resistant layer is a sliding surface.
12.
11. The piston ring according to 11 above, wherein the wear identification recess is provided from the outer peripheral surface of the base material to a certain depth.
13.
11. The piston ring according to 11 or 12, wherein a wear identification material made of a member different from the base material is fitted in the wear identification recess.
14.
13. The piston ring according to 13, wherein the top of the wear identification material is flush with the outer peripheral surface of the base material.
15.
13. The piston ring according to 13.
16.
15. The piston ring according to 15, wherein the wear identification material and the second wear identification material are formed as an integral member.
17.
15. The piston ring according to 15, wherein the wear identification material and the second wear identification material are formed as separate members.
18.
A piston ring made of a ring-shaped base material.
The outer peripheral surface of the base material is covered with the wear-resistant layer of the wear-resistant material, and the surface of the wear-resistant layer is a sliding surface.
A piston ring provided with a wear identification recess on the outer peripheral portion of the wear resistant layer.
19.
The piston ring according to any one of 11 to 18, wherein the wear identification recess has a shape representing a character or a figure when viewed from the outer peripheral side of the sliding surface.
20.
A piston ring made of a ring-shaped base material.
The outer peripheral surface of the base material is covered with the wear-resistant layer of the wear-resistant material, and the surface of the wear-resistant layer is a sliding surface.
A piston ring in which a wear identification material made of a member different from the wear-resistant layer is embedded in the wear-resistant layer.
21.
The piston ring according to any one of 13 to 17 and 20, wherein the wear identification material has a shape representing a character or a figure when viewed from the outer peripheral side of the sliding surface.

The present invention can provide a piston ring in which a wear-resistant layer made of a wear-resistant material is formed on the outer peripheral surface of the base material, and it is easy to determine the wear state of the wear-resistant layer from the appearance.

Perspective view of the piston ring according to the present invention Top view of the piston ring according to the present invention It is an enlarged view of the cross section along the line AA of FIG. Indicates a worn state. Enlarged perspective view of the main part in the first embodiment 2 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the second embodiment, where (a) is a state without wear, (b) is a state in which the familiar layer is worn, and (c) is a wear-resistant layer. The state of being worn, (d) indicates a state in which a certain amount of the base metal is worn. Enlarged perspective view and vertical cross-sectional view of the main part showing the steps (groove processing) (a) to (d) for manufacturing the wear identification recess in the third embodiment. An enlarged perspective view and a vertical sectional view of a main part showing a process for producing a wear-resistant layer (groove processing) (e) and a process for producing a familiar layer (f) in the third embodiment. It is an enlarged view of the cross section along the line AA of FIG. 1 in the 4th Embodiment, (a) is a state without wear, (b) is a state with wear on a familiar layer, (c) is a state with a familiar layer. The worn state, (d) indicates a state in which the wear-resistant layer is worn. 4 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the fourth embodiment, where FIG. 1E shows a state in which the wear-resistant layer is worn, and FIG. 1F shows a state in which the base metal is worn by a certain amount. 5 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the fifth embodiment, where (a) is a state without wear, (b) is a state in which the wear-resistant layer is worn, and (c) is a base material. Shows a certain amount of wear. It is an example of the manufacturing process of the fifth embodiment, and is an enlarged perspective view and a vertical sectional view of a main part showing the manufacturing process (groove processing) (a) to (e) of a wear identification recess and a familiar layer. 6 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the sixth embodiment, where (a) is a state without wear, (b) is a state in which the wear-resistant layer is worn, and (c) is a base material. Shows a certain amount of wear. 7 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the seventh embodiment, where (a) is a state without wear, (b) is a state where the wear-resistant layer is worn, and (c) is a wear-resistant layer. Indicates a state in which the base metal is worn out, and (d) indicates a state in which the base metal is worn by a certain amount. 8 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the eighth embodiment, where (a) is a state without wear, (b) is a state where the wear-resistant layer is worn, and (c) is a wear-resistant layer. Indicates a state of wear.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a piston ring according to the present invention. Further, FIG. 2 is a plan view of the piston ring according to the present invention.
In the piston ring according to the present invention, as shown in FIGS. 1 and 2, an outer peripheral layer 2 is formed on the outer periphery of the base material 1 formed in a ring shape. The outer peripheral layer 2 is provided with a wear resistant layer 2a made of a wear resistant material, and the outer peripheral surface of the wear resistant layer 2a is configured as a sliding surface 3. In the first to fourth embodiments, a familiar layer (familiar layer) 2b is further formed on the outer layer of the wear resistant layer 2a, and the outer peripheral surface of the familiar layer 2b is a sliding surface 3.
Of the wear-resistant layer 2a, the cermet (Ceramics Metal) layer that is sprayed or plated on the outer peripheral surface of the base material has little difference in color and surface shape from the base material. be.

[Invention of a piston ring in which a wear-resistant layer and a familiar layer (two layers) are formed]
Hereinafter, in the piston ring according to the present invention, the first to fourth embodiments in which a familiar layer is formed on the outer layer of the wear resistant layer will be described.

(First Embodiment)
3A and 3B are enlarged views of a cross section taken along the line AA of FIG. 1 in the first embodiment, where FIG. 3A is a state without wear, FIG. 3B is a state in which the familiar layer is worn out, and FIG. Indicates that the wear-resistant layer is worn out.

In this embodiment, as shown in FIG. 3A, the familiar layer 2b is laminated on the outer layer of the wear-resistant layer 2a to form a sliding surface 3 to the cylinder liner. That is, the outer peripheral surface of the familiar layer 2b becomes a flush sliding surface 3.

The base metal 1 is not particularly limited, but is made of various cast iron, cast steel, carbon steel for general structure, copper alloy, sintered alloy and the like.

The wear-resistant layer 2a is made of a wear-resistant material, for example, a ceramic material such as Cr ₃ C ₂ , Al ₂ O ₃ , WC, Cr ₂ O ₃ , ZrO ₂ , and Cr, Co, Ni, Mo, Fe. Cermet to which a metal such as Cu or Cu is added is preferably used.
Further, the wear-resistant layer 2a is formed by, for example, thermal spraying, electrolyte plating, or electrolyte plating, and an electrolyte plating layer containing ceramic particles.
The thickness of the wear-resistant layer 2a is, for example, about 0.3 to 0.6 mm.

The outer peripheral surface of the familiar layer 2b is a sliding surface 3 to the cylinder liner, and is, for example, a metal such as Cr, Co, Ni, Mo, Fe, Cu or a mixture thereof, or Cr _3C ₂ , WC. , Al ₂ O ₃ and other ceramic materials, or composite materials thereof.
Further, the familiar layer 2b is formed by, for example, thermal spraying, electrolyte plating, or chrome ceramic composite plating.
The thickness of the familiar layer 2b is, for example, about 0.1 to 0.3 mm.

Here, the familiar layer 2b is a layer provided so as to be worn early after the start of use and to adapt the shape of the sliding surface 3 to the shape of the inner surface of the cylinder.

In this embodiment, the wear identification material 4 is provided on the outer peripheral surface of the base material 1. The wear identification material 4 is made of a member different from the base material 1. The wear identification material 4 preferably has a different color from any of the familiar layer 2b, the wear resistant layer 2a, and the base material 1. This makes it easy to distinguish the wear identification material 4 from the familiar layer 2b, the wear resistant layer 2a, and the base material 1.

For the wear identification material 4, for example, after the wear-resistant layer 2a and the familiar layer 2b are formed, a pin-shaped member is driven in at a depth reaching the base material 1 from the sliding surface 3, or the wear-resistant layer 2a and the familiar layer 2a and the familiar layer 4 are used. It is arranged by forming a hole in the layer 2b and inserting a wear identification material made of another member, or by forming a recess in the wear resistant layer 2a and the familiar layer 2b and filling the recess by welding or thermal spraying. Can be done.

In the sliding surface 3, the top of the wear identification material 4 may face outward and be flush with the sliding surface 3, or the familiar layer 2b may cover the top of the wear identification material 4. .. When the top of the wear identification material 4 faces outward, the top of the wear identification material 4 forms a part of the sliding surface 3.

The wear identification material 4 is preferably made of a material having the same wear resistance as the material forming the wear resistant layer 2a or having a low wear resistance. This is because if the wear resistance of the wear identification material 4 is higher than that of the wear resistance layer 2a, only the wear identification material 4 may remain and protrude from the sliding surface 3 when the wear resistance layer 2a is worn. ..

FIG. 4 is an enlarged perspective view of a main part in the first embodiment.

As shown in FIG. 4, the wear identification material 4 preferably has a shape representing characters and figures when viewed from the outer peripheral side of the sliding surface 3 in order to facilitate identification of the wear state.
Similarly, the wear identification recess 5, which will be described later, is preferably shaped to represent characters and figures when viewed from the outer peripheral side of the sliding surface 3 in order to facilitate identification of the wear state.

In this piston ring, when the sliding surface 3 is worn and the familiar layer 2b is worn away, the wear resistant layer 2a appears as shown in FIG. 3 (b). At this time, the wear of the familiar layer 2b can be identified from the appearance by the difference in color between the familiar layer 2b and the wear-resistant layer 2a.

It is also preferable to change the shape of the cross section of the wear identification material 4 (cross section parallel to the sliding surface 3) according to the height of the wear identification material 4 (depth from the initial sliding surface 3). Thereby, the wear and wear of the familiar layer 2b can be discriminated by the shape of the top of the wear identification material 4.

Further, when the wear-resistant layer 2a is worn away, the base metal 1 appears as shown in FIG. 3 (c). At this time, the wear of the wear-resistant layer 2a can be identified from the appearance by the disappearance of the wear identification material 4. At this time, the piston ring can be replaced as the replacement timing.

The piston ring should be replaced when the wear-resistant layer 2a is worn, but the wear identification material 4 has a limit of the amount of wear of the base material 1 that maintains the required sealing performance (for example, 1. It is also preferable to be able to further discriminate (about 5 to 2 mm). That is, it is also preferable that the wear identification material 4 is provided so as to penetrate into the base material 1 by a certain amount of depth.

Further, if another member forming the wear identification material 4 is allowed to enter the base material 1 to a certain depth, the wear identification material 4 is worn when the base material 1 is worn by a certain amount without replacing the piston ring. Disappears, so that it can be identified from the appearance that the base material 1 has been worn by a certain amount.

As described above, the piston ring can identify the presence / absence of the familiar layer 2b and the wear-resistant layer 2a, or the wear state of the base material 1 from the appearance.
Therefore, with this piston ring, it becomes easy to adjust the lubrication rate and determine the piston ring replacement timing, and the adjustment / replacement can be performed at an appropriate timing, which can contribute to safe operation. With this piston ring, it is possible to reduce the time and effort required to measure the wear status of engineers and sailors, and it is expected that the inspection time for the piston ring will be reduced. In addition, CBM (Condition Based Maintenance) becomes possible as a part of continuous monitoring of the appearance of the piston ring (cylinder condition monitor).

(Second embodiment)
5A and 5B are enlarged views of a cross section taken along the line AA of FIG. 1 in the second embodiment, where FIG. 5A is a state without wear, FIG. 5B is a state in which the familiar layer is worn out, and FIG. The wear-resistant layer is worn, and (d) is a state in which the base metal is worn by a certain amount.
The material and overall shape of the base material 1, the material and the manufacturing method of the wear-resistant layer 2a and the familiar layer 2b refer to the description of the first embodiment, and are omitted here.

In this embodiment, as shown in FIG. 5, a wear identification recess 5 is provided on the outer peripheral surface of the base material 1. The wear identification recess 5 can be formed by cutting or drilling the base material 1 before forming the wear resistant layer 2a and the familiar layer 2b. It is preferable that the wear identification recess 5 has a certain depth from the outer peripheral surface of the base material 1.

The wear identification recess 5 is preferably shaped to represent characters or figures when viewed from the outer peripheral side of the sliding surface 3 in order to facilitate identification of the wear state.

In this piston ring, when the sliding surface 3 is worn and the familiar layer 2b is worn away, the wear resistant layer 2a appears as shown in FIG. 5 (b). At this time, the wear of the familiar layer 2b can be identified from the appearance by the difference in color between the familiar layer 2b and the wear-resistant layer 2a.

Further, when the wear-resistant layer 2a is worn away, the base metal 1 appears as shown in FIG. 5 (c). At this time, the wear of the wear-resistant layer 2a can be identified from the appearance by the appearance of the wear identification recess 5. At this time, the piston ring can be replaced as the replacement timing.

Further, the depth of the wear identification recess 5 is set to a certain amount from the outer peripheral surface of the base material 1, and as shown in FIG. 5D, the base material 1 has a constant amount without replacing the piston ring. Since the wear identification recess 5 disappears when worn, it is possible to identify from the appearance that the base material 1 has been worn by a certain amount.

Further, the state in which the familiar layer 2b is worn out (FIG. 5 (b)) and the state in which the base metal 1 is worn by a certain amount (FIG. 5 (d)) are the states of the outer peripheral corners of the piston ring (the state of the R surface). It is also possible to distinguish between the wear-resistant layer 2a and the base material 1 by the difference between the two.

Further, if the cross-sectional shape (cross section parallel to the sliding surface 3) of the wear identification recess 5 is changed according to the depth of the wear identification recess 5, the base material can be changed depending on the visible shape of the wear identification recess 5. The wear state of 1 can be identified.

Further, a wear identification material made of a member different from the base material 1 may be fitted into the wear identification recess 5, and in this case, the appearance that the base material 1 is worn by a certain amount by disappearing the wear identification material. Can be identified from.

(Third embodiment)
FIG. 6A is an enlarged perspective view and a vertical cross-sectional view of a main part showing the steps (groove processing) (a) to (d) for manufacturing the wear identification recess in the third embodiment.
FIG. 6B is an enlarged perspective view and a vertical sectional view of a main part showing a wear-resistant layer manufacturing step (groove processing) (e) and a familiar layer manufacturing step (f) in the third embodiment.
As shown in FIG. 6A, the wear identification recess 5 may be formed by grooving.
The material and overall shape of the base material 1, the material and the manufacturing method of the wear-resistant layer 2a and the familiar layer 2b refer to the description of the first embodiment, and are omitted here.

First, as shown in FIGS. 6A (a) and 6 (b), a wear identification recess 5 which is a groove is formed on the base material 1 by using a milling cutter 101.
Next, as shown in FIG. 6A (c), the wear identification recess 5 is filled with the welding material 6 serving as the wear identification material 4. The welding material 6 preferably has a color different from that of the wear-resistant layer 2a and the base material 1.
Then, as shown in FIG. 6A (d), the welding material 6 in which the wear identification recess 5 is filled is polished so as to be flush with the outer peripheral surface of the base material 1.
As shown in FIG. 6B (e), a wear-resistant layer 2a is formed on the outer peripheral surface of the base metal 1.
As shown in FIG. 6B (f), a familiar layer 2b is formed on the outer peripheral surface of the wear resistant layer 2a.

In this piston ring, when the wear-resistant layer 2a is worn away, a wear identification recess 5 filled by welding appears. Since the welding material 6 in which the wear identification recess 5 is filled has a color different from that of the wear resistant layer 2a and the base material 1, it can be discriminated from the appearance that the wear resistant layer 2a is worn.

(Fourth Embodiment)
7A is an enlarged view of a cross section taken along the line AA of FIG. 1 in the fourth embodiment, where (a) is a state without wear, (b) is a state where the familiar layer is worn, and (c). Indicates a state in which the familiar layer is worn, and (d) indicates a state in which the wear-resistant layer is worn.
7B is an enlarged view of a cross section taken along the line AA of FIG. 1 in the fourth embodiment. FIG. 7B is a state in which the wear-resistant layer is worn, and FIG. 7B is a state in which the base metal is worn by a certain amount. Is shown.
The material and overall shape of the base material 1, the material and the manufacturing method of the wear-resistant layer 2a and the familiar layer 2b refer to the description of the first embodiment, and are omitted here.

In this embodiment, as shown in FIG. 7A, a wear identification recess 5 is provided on the outer peripheral surface of the base material 1, and the depth is from the surface of the wear-resistant layer 2a to half the thickness of the wear-resistant layer 2a. The first wear identification recess 5a is formed, and the second wear identification recess 5b is formed at a depth from the surface of the familiar layer 2b to half the thickness of the wear resistant layer 2a.

The wear identification recess 5 can be formed by cutting or drilling the base material 1 before forming the wear resistant layer 2a and the familiar layer 2b. It is preferable that the wear identification recess 5 has a certain depth from the outer peripheral surface of the base material 1. The first wear identification recess 5a can be formed by cutting or drilling the wear resistant layer 2a before forming the familiar layer 2b. The second wear identification recess 5b can be formed by cutting or drilling the familiar layer 2b.

A wear identification material made of a member different from the base material 1 may be fitted into the wear identification recess 5. A wear identification material made of a member different from the wear resistant layer 2a may be fitted into the first wear identification recess 5a. A wear identification material made of a member different from the familiar layer 2b may be fitted into the second wear identification recess 5b.

A wear identification material may be embedded in the wear resistant layer 2a and / or the familiar layer 2b. That is, the top of the wear identification material may be covered with the wear resistant layer 2a and / or the familiar layer 2b. Further, the bottom portion of the wear identification material does not have to reach the outer peripheral surface of the inner layer. The bottom is the inner layer, whether the top faces the outer or outer layer, or the top is inside the wear-resistant layer 2a and / or the familiar layer 2b and is covered by the wear-resistant layer 2a and / or the familiar layer 2b. Both the state of being in contact with the outer peripheral surface of the inner layer and the state of the bottom being separated from the outer peripheral surface of the inner layer are buried. In order to cover the top of the wear identification material with the wear resistant layer 2a and / or the familiar layer 2b, the wear resistant layer 2a and / or the familiar layer 2b is formed after the wear identification material is provided.

Further, the wear identification recess 5, the first wear identification recess 5a and / or the second wear identification recess 5b have characters and figures viewed from the outer peripheral side of the sliding surface 3 in order to facilitate identification of the wear state. It is preferable that the shape is represented.

In this piston ring, when the sliding surface 3 is worn and the familiar layer 2b is worn by more than half the thickness, the second wear identification recess 5b or the wear identification material disappears as shown in FIG. 7A (b). Further, when the familiar layer 2b is completely worn away, as shown in FIG. 7A (c), the first wear identification recess 5a or the wear identification material formed in the wear resistant layer 2a appears. At this time, it is also identified that the familiar layer 2b is worn out by the difference in color between the familiar layer 2b and the wear-resistant layer 2a. When the wear-resistant layer 2a wears more than half of its thickness, the first wear identification recess 5a or the wear identification material disappears as shown in FIG. 7A (d). Further, when the wear-resistant layer 2a is completely worn away, as shown in FIG. 7B (e), the base material 1 having the wear identification recess 5 appears. At this time, the piston ring can be replaced as the replacement timing.

Further, if the depth of the wear identification recess 5 is set to a certain amount of depth from the outer peripheral surface of the base material 1, as shown in FIG. 7B (f), the base material 1 wears a certain amount without replacing the piston ring. Since the wear identification recess 5 or the wear identification material disappears at that time, it is possible to identify from the appearance that the base material 1 has been worn by a certain amount.

As described above, in this piston ring, the fact that the familiar layer 2b is half worn can be identified from the appearance by the disappearance of the second wear identification recess 5b or the wear identification material. Further, the wear of the familiar layer 2b can be identified from the appearance by the appearance of the first wear identification recess 5a or the wear identification material and the difference in color between the familiar layer 2b and the wear resistant layer 2a. Further, it can be identified from the appearance that the wear-resistant layer 2a is half worn by the first wear identification recess 5a or the wear identification material disappearing. Further, the wear of the wear-resistant layer 2a can be identified from the appearance by the appearance of the wear identification recess 5 or the wear identification material.

Further, it can be identified from the appearance that the base material 1 is worn by a certain amount by the wear identification recess 5 or the wear identification material disappearing.

The state in which the wear-resistant layer 2a is worn (FIG. 7A (d)) and the state in which the base metal 1 is worn by a certain amount (FIG. 7B (f)) are the states of the outer peripheral corners of the piston ring (R surface). The wear-resistant layer 2a and the base material 1 can be distinguished from each other by the difference in the state).

Further, the cross-sectional shape (cross section parallel to the sliding surface 3) of the wear identification recess 5, the first wear identification recess 5a and the second wear identification recess 5b is determined by the depth of the

wear identification recesses

5, 5a and 5b. If it is changed, the wear state of the familiar layer 2b, the wear-resistant layer 2a, and the base material 1 can be identified by the visible shapes of the

wear identification recesses

5, 5a, and 5b.

(Other embodiments)
In each of the piston rings on which the wear-resistant layer and the familiar layer (two layers) are formed, the color of the base material 1 is red and the color of the wear-resistant layer 2a is blue instead of the wear identification material 4 and the wear identification recess 5. If the color of the familiar layer 2b is colored (color-coded) as yellow or the like, the wear state of the familiar layer 2b and the wear-resistant layer 2a can be identified from the appearance by the color of the surface of the sliding surface 3. That is, if the yellow familiar layer 2b is worn out, the blue wear-resistant layer 2a appears on the surface of the sliding surface 3, and if the wear-resistant layer 2a is worn out, the red base material 1 is on the surface of the sliding surface 3. Appears in.

[Invention of a piston ring in which only a wear-resistant layer (single layer) is formed]
Hereinafter, in the piston ring according to the present invention, the fifth to eighth embodiments in which only the wear-resistant layer (single layer) is formed will be described.

(Fifth Embodiment)
FIG. 8 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the fifth embodiment, where (a) is a state without wear, (b) is a state in which the wear-resistant layer is worn, and (c). Indicates that the base metal has been worn by a certain amount.

In this embodiment, as shown in FIG. 8, the outer peripheral surface of the base material 1 is covered with the wear-resistant layer 2a of the wear-resistant material, and the surface of the wear-resistant layer 2a becomes the sliding surface 3 to the cylinder liner. There is. The wear-resistant layer 2a is a single layer in this embodiment, but is not limited to this, and a plurality of layers made of different materials may be laminated.

In this embodiment, as shown in FIG. 8A, a wear identification recess 5 is provided on the outer peripheral surface of the base material 1. It is preferable that the wear identification material 4 is fitted in the wear identification recess 5. The wear identification material 4 is made of a member different from the base material 1. The wear identification material 4 preferably has a color different from that of the base material 1. This makes it easy to distinguish between the wear identification material 4 and the base material 1.

However, the wear identification material 4 does not necessarily have to be provided. When the wear identification material 4 is not provided, the wear identification recess 5 is opened on the outer peripheral surface of the base material 1.

It is preferable that the wear identification material 4 is provided in the base material 1 by allowing it to penetrate into the base material 1 by a certain amount of depth from the outer peripheral surface of the base material 1. If the wear identification material 4 is allowed to enter the base material 1 by a certain amount of depth from the outer peripheral surface of the base material 1, the top of the wear identification material 4 disappears when the base material 1 is worn by a certain amount. It can be identified from the appearance that the base material 1 has been worn by a certain amount.

In this embodiment, the top of the wear identification material 4 is flush with the outer peripheral surface of the base material 1. However, on the sliding surface 3, as in the sixth embodiment described later, the top of the wear identification material 4 may face outward and be flush with the sliding surface 3. When the top of the wear identification material 4 faces outward, the top of the wear identification material 4 forms a part of the sliding surface 3. Further, the top of the wear identification material 4 may be covered with the wear resistant layer 2a.

The wear identification material 4 is preferably made of a material having the same wear resistance as the material forming the wear resistant layer 2a and the material forming the base material 1, or having a low wear resistance. If the wear resistance of the wear identification material 4 is higher than that of the wear resistance layer 2a and the base material 1, only the wear identification material 4 remains when the wear resistance layer 2a and the base material 1 are worn, and protrudes from the sliding surface 3. This is because there is a risk that it will end up.

The wear identification recess 5 and the wear identification material 4 are preferably shaped to represent characters or figures when viewed from the outer peripheral side of the sliding surface 3 in order to facilitate identification of the wear state.

In this piston ring, when the sliding surface 3 is worn and the wear-resistant layer 2a is worn away, the outer peripheral surface of the base material 1 appears as shown in FIG. 8 (b), and the wear identification recess 5 and / or the wear identification is performed. Since the material 4 appears, it can be identified from the appearance that the wear-resistant layer 2a is worn out. At this time, the piston ring can be replaced as the replacement timing.

The cross-sectional shape (cross section parallel to the sliding surface 3) of the wear identification recess 5 and the wear identification material 4 depends on the depth of the wear identification recess 5 and the wear identification material 4 (depth from the initial sliding surface 3). It is also preferable to change it. As a result, when the wear-resistant layer 2a or the base material 1 wears, as shown in FIG. 8B, the base material 1 wears from the appearance due to the shape of the open end of the wear identification recess 5 and the top of the wear identification material 4. The state can be identified.

Further, if the depth of the wear identification recess 5 is set to a certain amount from the outer peripheral surface of the base material 1, as shown in FIG. 8C, the base material 1 wears a certain amount without replacing the piston ring. When this is done, the wear identification recess 5 and / or the wear identification material 4 disappears. At this time, the wear of the base material 1 by a certain amount can be identified from the appearance by the wear identification recess 5 and / or the wear identification material 4 disappearing.

The state where there is no wear (FIG. 8 (a)) and the state where the base metal 1 is worn by a certain amount (FIG. 8 (c)) are different depending on the state of the outer peripheral corner portion of the piston ring (the state of the R surface). It is also possible to distinguish between the wear-resistant layer 2a and the base material 1.

In this way, this piston ring can identify the wear status of the base material 1 from the appearance. Therefore, with this piston ring, it becomes easy to adjust the lubrication rate and determine the piston ring replacement timing, and the adjustment / replacement can be performed at an appropriate timing, which can contribute to safe operation. With this piston ring, it is possible to reduce the time and effort required to measure the wear status of engineers and sailors, and it is expected that the inspection time for the piston ring will be reduced. In addition, CBM (Condition Based Maintenance) is possible as part of the constant monitoring of the appearance of the piston ring (cylinder condition monitor).

FIG. 9 is an example of the manufacturing process of the fifth embodiment, and is an enlarged perspective view and a vertical sectional view of a main part showing the manufacturing steps (groove processing) (a) to (e) of the wear identification recess and the wear resistant layer. be.
As shown in FIG. 9, the wear identification recess 5 may be formed by grooving.

First, as shown in FIGS. 9A and 9B, a wear identification recess 5 which is a groove is formed on the base material 1 by using a milling cutter 101.
Next, as shown in FIG. 9C, the wear identification recess 5 is filled with the welding material 6 serving as the wear identification material 4. The welding material 6 preferably has a color different from that of the wear-resistant layer 2a and the base material 1.
Then, as shown in FIG. 9D, the welding material 6 in which the wear identification recess 5 is filled is polished so as to be flush with the outer peripheral surface of the base material 1.
As shown in FIG. 9 (e), a wear-resistant layer 2a is formed on the outer peripheral surface of the base metal 1.

In this piston ring, when the wear-resistant layer 2a is worn away, the welding material 6 and the wear identification recess 5 appear. Since the welding material 6 in which the wear identification recess 5 is filled has a color different from that of the wear resistant layer 2a and the base material 1, it can be discriminated from the appearance that the wear resistant layer 2a is worn.

(Sixth Embodiment)
10 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the sixth embodiment, where (a) is a state without wear, (b) is a state where the wear-resistant layer is worn, and (c). Indicates that the base metal has been worn by a certain amount.
The material and overall shape of the base material 1, the material and the manufacturing method of the wear-resistant layer 2a refer to the description of the fifth embodiment, and are omitted here.

In this embodiment, as shown in FIG. 10, the outer peripheral surface of the base material 1 is covered with the wear-resistant layer 2a of the wear-resistant material, and the surface of the wear-resistant layer 2a becomes the sliding surface 3 to the cylinder liner. There is. The wear-resistant layer 2a is a single layer in this embodiment, but is not limited to this, and a plurality of layers made of different materials may be laminated.

Also in this embodiment, as shown in FIG. 10A, a wear identification recess 5 is provided on the outer peripheral surface of the base material 1 from the outer peripheral surface of the base material 1 to a certain depth. Further, a first wear identification material 4a made of a member different from the base material 1 is fitted in the wear identification recess 5.

However, it is not always necessary to provide the first wear identification material 4a. When the first wear identification material 4a is not provided, the wear identification recess 5 is opened on the surface of the wear resistant layer 2a.

In this embodiment, a second wear identification material 4b made of a member different from the wear resistant layer 2a is embedded in the wear resistant layer 2a. In this embodiment, the second wear identification material 4b is integrated with the first wear identification material 4a to form the wear identification material 4. That is, the wear identification material 4 extends from the inside of the wear identification recess 5 to the inside of the wear resistant layer 2a.

The top of the wear identification material 4 faces outward and is flush with the sliding surface 3, and the top of the wear identification material 4 forms a part of the sliding surface 3. The wear identification material 4 may be inside the wear resistant layer 2a and covered with the wear resistant layer 2a. Here, in the burial in the present embodiment, even in a state where the top faces outward and is flush with the sliding surface 3, the top is inside the wear-resistant layer 2a and is covered by the wear-resistant layer 2a. Including the state of being. In order to cover the top of the wear identification material 4 with the wear resistance layer 2a, the wear resistance layer 2a is formed after the wear identification material 4 is provided.

The cross-sectional shape (cross section parallel to the sliding surface 3) of the wear identification recess 5 and the wear identification material 4 depends on the depth of the wear identification recess 5 and the wear identification material 4 (depth from the initial sliding surface 3). It is preferable to change it. As a result, when the wear-resistant layer 2a is worn, it can be identified that the wear-resistant layer 2a is worn by the shape of the open end of the wear identification recess 5 and / or the top of the wear identification material 4.

In this piston ring, when the sliding surface 3 is worn and the wear-resistant layer 2a is worn away, the outer peripheral surface of the base material 1 appears as shown in FIG. 10 (b). At this time, the piston ring can be replaced as the replacement timing.

When the base material 1 wears a certain amount without replacing the piston ring, the wear identification recess 5 and / or the wear identification material 4 disappears as shown in FIG. 10 (c). At this time, the fact that the base material 1 has reached a certain amount can be identified from the appearance by the disappearance of the wear identification recess 5 and / or the wear identification material 4.

When the wear identification material 4 is covered with the wear resistant layer 2a, the state where there is no wear (FIG. 10 (a)) and the state where the base material 1 is worn by a certain amount (FIG. 10 (c)) are referred to as a state where there is no wear (FIG. 10 (a)). The wear-resistant layer 2a and the base metal 1 can be distinguished from each other by the difference in the state of the outer peripheral corner portion (the state of the R surface) of the piston ring.

In this embodiment, the first wear identification material 4a and the second wear identification material 4b are regarded as an integral member to form the wear identification material 4, but these first and second wear identification materials are used. The

materials

4a and 4b may be separate members, and in this case, they may be provided at different positions when viewed from the outer peripheral side.

(7th Embodiment)
11 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the seventh embodiment, where (a) is a state without wear, (b) is a state where the wear-resistant layer is worn, and (c). Indicates a state in which the wear-resistant layer is worn, and (d) indicates a state in which the base metal is worn by a certain amount.
The material and overall shape of the base material 1, the material and the manufacturing method of the wear-resistant layer 2a refer to the description of the fifth embodiment, and are omitted here.

In this embodiment, as shown in FIG. 11, the outer peripheral surface of the base material 1 is covered with the wear-resistant layer 2a of the wear-resistant material, and the surface of the wear-resistant layer 2a becomes the sliding surface 3 to the cylinder liner. There is. The wear-resistant layer 2a is a single layer in this embodiment, but is not limited to this, and a plurality of layers made of different materials may be laminated.

Also in this embodiment, as shown in FIG. 11A, a first wear identification recess 5a is provided on the outer peripheral surface of the base material 1 in a constant amount from the outer peripheral surface of the base material 1 to the outer peripheral surface of the base material 1. It is provided to the depth. Further, a first wear identification material 4a made of a member different from the base material 1 is fitted in the first wear identification recess 5a. However, the first wear identification material 4a does not necessarily have to be provided. When the first wear identification material 4a is not provided, the first wear identification recess 5a is opened on the outer peripheral surface of the base material 1.

In this embodiment, the top of the first wear identification material 4a is flush with the outer peripheral surface of the base material 1. However, on the sliding surface 3, as in the sixth embodiment described above, the top of the first wear identification material 4a may face outward and be flush with the sliding surface 3. When the top of the first wear identification material 4a faces outward, the top of the first wear identification material 4a forms a part of the sliding surface 3. Further, the top of the first wear identification material 4a may be inside the wear resistant layer 2a and covered with the wear resistant layer 2a. In order to cover the top of the first wear identification material 4a with the wear resistance layer 2a, the wear resistance layer 2a is formed after the first wear identification material 4a is provided.

The wear-resistant layer 2a is provided with a second wear-identifying recess 5b over a predetermined depth from the surface of the wear-resistant layer 2a. The second wear identification recess 5b is provided at a position different from that of the first wear identification recess 5a of the base material 1 (a position that does not overlap in the radial direction of the piston ring). A second wear identification material 4b made of a member different from the wear resistant layer 2a is fitted into the second wear identification recess 5b and is embedded in the wear resistant layer 2a. In this embodiment, the second wear identification material 4b is a member separate from the first wear identification material 4a in the first wear identification recess 5a. However, the second wear identification material 4b does not necessarily have to be provided. When the second wear identification material 4b is not provided, the second wear identification recess 5b is opened on the surface of the wear resistant layer 2a.

In this embodiment, the top of the second wear identification material 4b faces outward and is flush with the surface of the wear resistant layer 2a. The top of the second wear identification material 4b forms a part of the sliding surface 3. However, the top of the second wear identification material 4b may be covered with the wear resistant layer 2a. Here, in the burying in the present embodiment, the bottom portion of the second wear identification material 4b is in contact with the outer peripheral surface of the base material 1, and the top portion faces outward and is flush with the sliding surface 3. Alternatively, the top is inside the wear-resistant layer 2a and is covered by the wear-resistant layer 2a, or the bottom of the second wear identification material 4b is separated from the outer peripheral surface of the base material 1 and the top faces outward. This includes a state in which the surface is flush with the sliding surface 3 or a state in which the top portion is inside the wear-resistant layer 2a and is covered by the wear-resistant layer 2a. In order to cover the top of the second wear identification material 4b with the wear resistance layer 2a, the wear resistance layer 2a is formed after the second wear identification material 4b is provided.

The first and second

wear identification materials

4a and 4b are preferably made of a material having the same wear resistance as the material forming the wear resistant layer 2a and the material forming the base material 1, or having a low wear resistance. If the wear resistance of the first and second

wear identification materials

4a and 4b is higher than that of the wear resistant layer 2a and the base material 1, the first and second wears when the wear resistant layer 2a and the base material 1 are worn. This is because only the

identification materials

4a and 4b may remain and protrude from the sliding surface 3.

The first and second

wear identification recesses

5a and 5b, and the first and second

wear identification materials

4a and 4b have characters and figures viewed from the outer peripheral side of the sliding surface 3 in order to facilitate identification of the wear state. It is preferable that the shape represents.

The cross-sectional (cross-section parallel to the sliding surface 3) shape of the first and second

wear identification recesses

5a and 5b and the first and second

wear identification materials

4a and 4b is the first and second wear identification recesses. It is also preferable to change the depth according to the depths of the 5a and 5b, the first and second

wear identification materials

4a and 4b (the depth from the initial sliding surface 3). As a result, when the wear-resistant layer 2a and the base material 1 are worn, the appearance is changed by the shapes of the openings of the first and second

wear identification recesses

5a and 5b and the tops of the first and second

wear identification materials

4a and 4b. It is possible to identify the wear state of the wear-resistant layer 2a and the base material 1 from the above.

In this piston ring, when the sliding surface 3 is worn and the wear-resistant layer 2a becomes thin, the second wear identification recess 5b and the second wear identification material 4b disappear as shown in FIG. 11B. At this time, the wear of the wear-resistant layer 2a can be identified from the appearance by the disappearance of the second wear identification recess 5b and / or the second wear identification material 4b.

Further, when the sliding surface 3 is worn and the wear-resistant layer 2a is worn away, the outer peripheral surface of the base material 1 appears as shown in FIG. 11 (c), and the first wear identification recess 5a and / or the first wear The identification material 4a appears. At this time, the piston ring can be replaced as the replacement timing.

When the base material 1 wears a certain amount without replacing the piston ring, the first wear identification recess 5a and / or the first wear identification material 4a disappears as shown in FIG. 11D. At this time, the fact that the base material 1 has reached a certain amount can be identified from the appearance by the disappearance of the first wear identification recess 5a and / or the first wear identification material 4a.

The state in which the wear-resistant layer 2a is worn (FIG. 11 (b)) and the state in which the base metal 1 is worn by a certain amount (FIG. 11 (d)) are the states of the outer peripheral corners of the piston ring (the state of the R surface). ), It is also possible to distinguish between the wear-resistant layer 2a and the base material 1.

(8th Embodiment)
12 is an enlarged view of a cross section taken along the line AA of FIG. 1 in the eighth embodiment, where (a) is a state without wear, (b) is a state where the wear-resistant layer is worn, and (c). Indicates that the wear-resistant layer is worn out.
The material and overall shape of the base material 1, the material and the manufacturing method of the wear-resistant layer 2a refer to the description of the fifth embodiment, and are omitted here.

In this embodiment, as shown in FIG. 12, the outer peripheral surface of the base material 1 is covered with the wear-resistant layer 2a of the wear-resistant material, and the surface of the wear-resistant layer 2a becomes the sliding surface 3 to the cylinder liner. There is. The wear-resistant layer 2a is a single layer in this embodiment, but is not limited to this, and a plurality of layers made of different materials may be laminated.

In this embodiment, as shown in FIG. 12A, the wear-resistant layer 2a is provided with a wear-identifying recess 5 extending from the surface of the wear-resistant layer 2a to the outer peripheral surface of the base material 1. A wear identification material 4 made of a member different from the wear-resistant layer 2a is fitted into the wear-identifying recess 5, and is embedded in the wear-resistant layer 2a. However, the wear identification material 4 does not necessarily have to be provided. When the wear identification material 4 is not provided, the wear identification recess 5 is opened on the surface of the wear resistant layer 2a.

In this embodiment, the top of the wear identification material 4 faces outward and is flush with the surface of the wear resistant layer 2a. The top of the wear identification material 4 forms a part of the sliding surface 3. However, the top of the wear identification material 4 may be covered with the wear resistant layer 2a. Further, the bottoms of the wear identification recess 5 and the wear identification material 4 do not have to reach the outer peripheral surface of the base material 1. The bottom is the outer periphery of the base material 1 regardless of whether the top faces the outside and is flush with the sliding surface 3 or the top is inside the wear-resistant layer 2a and is covered by the wear-resistant layer 2a. Both the state of being in contact with the surface and the state of the bottom being separated from the outer peripheral surface of the base material 1 are buried. In order to cover the top of the wear identification material 4 with the wear resistance layer 2a, the wear resistance layer 2a is formed after the wear identification material 4 is provided.

The cross-sectional shape (cross section parallel to the sliding surface 3) of the wear identification recess 5 and the wear identification material 4 depends on the depth of the wear identification recess 5 and the wear identification material 4 (depth from the initial sliding surface 3). It is also preferable to change it. As a result, when the wear-resistant layer 2a is worn, the wear state of the wear-resistant layer 2a can be identified from the appearance by the shape of the open end of the wear identification recess 5 and / or the top of the wear identification material 4.

In this piston ring, when the sliding surface 3 is worn and the wear-resistant layer 2a becomes thin, the cross-sectional shapes of the wear identification recess 5 and the wear identification material 4 change depending on the depth, as shown in FIG. 12 (b). If so, the shape of the opening of the wear identification recess 5 and / or the top of the wear identification material 4 changes. At this time, the wear of the wear-resistant layer 2a can be identified from the appearance by the change in the shape of the opening of the wear identification recess 5 and / or the top of the wear identification material 4.

Further, when the sliding surface 3 is worn and the wear-resistant layer 2a is worn away, as shown in FIG. 12 (c), the wear identification recess 5 and / or the wear identification material 4 disappears, and the outer peripheral surface of the base material 1 appears. At this time, the wear of the wear-resistant layer 2a can be identified from the appearance by the disappearance of the wear identification recess 5 and / or the wear identification material 4. At this time, the piston ring can be replaced as the replacement timing.

When the wear identification material 4 is covered with the wear-resistant layer 2a, the state without wear (FIG. 12 (a)) and the state where the wear-resistant layer 2a is worn (FIG. 12 (c)) are the pistons. The wear-resistant layer 2a and the base metal 1 can be distinguished from each other by the difference in the state of the outer peripheral corner portion of the ring (the state of the R surface).

(Other embodiments)
In each piston ring in which only the wear-resistant layer (single layer) is formed, the color of the base material 1 is red and the color of the wear-resistant layer 2a is blue or yellow instead of the wear identification material 4 and the wear identification recess 5. By coloring (color-coding) such as, the wear state of the wear-resistant layer 2a can be identified from the appearance by the color of the surface of the sliding surface 3. That is, when the blue or yellow wear-resistant layer 2a is worn away, the red base material 1 appears on the surface of the sliding surface 3.

[Usage mode in internal combustion engine]
In an internal combustion engine, the piston ring described above is a position that can be seen from the outside (a position that is easy to see) when the engine is stopped and the piston is moved downward so that the sliding surface 3 of the piston ring can be seen from the outside. Is provided with a wear identification recess 5 and / or a wear identification material 4.
For example, if there is only one position on the sliding surface 3 that can be seen from the outside (a position that is easy to see), a wear identification recess 5 and / or a wear identification material 4 can be provided at this location.
Alternatively, by providing the wear identification recess 5 and / or the wear identification material 4 at a plurality of locations on the sliding surface 3 at equal angle intervals, the wear identification recess 5 and / or the wear identification material 4 can be seen from the outside (a position that is easy to see). ) Can be.
Alternatively, by providing the wear identification recess 5 and / or the wear identification material 4 at a plurality of locations on the sliding surface 3 at unequal intervals such as, for example, 5 °, 40 °, 5 °, 40 °, etc., one Even if the wear identification recess 5 and / or the wear identification material 4 that came to the front is hidden by a rib or the like, another wear identification recess 5 and / or the wear identification material 4 is present in the immediate vicinity to facilitate identification. be able to.
The wear identification recess 5 and / or the wear identification material 4 may be provided over the entire circumference of the sliding surface 3.

The identification of the worn state of the piston ring has not been easy in the past because it is performed by the crew of the ship who does not have sufficient knowledge about the piston ring in the engine room of the ship which is not sufficiently bright.
By using the piston ring according to the present invention, even a crew member who does not have knowledge about the piston ring in a dark engine room can easily identify the wear state of the piston ring from the appearance by the wear identification recess 5 or the wear identification material 4. This makes it easier to adjust the lubrication rate and determine the piston ring replacement timing, and it is possible to carry out adjustment and replacement at an appropriate timing, which contributes to safe operation.

The numerical values and material names relating to the size, weight, etc. shown in each of the above-described embodiments are examples and do not limit the present invention in any way. The present invention is construed as not limited to these numerical values and material names.
Further, within the scope of the technical idea of the present invention, each of the above embodiments can be appropriately combined.

1 Base material 2 Outer peripheral layer 2a Abrasion resistant layer 2b Familiar layer 3 Sliding surface 4 Abrasion identification material 4a First wear identification material 4b Second wear identification material 5 Wear identification recess 5a First wear identification recess 5b Second Wear identification recess 6 Welding material 101 Milling cutter

Claims

A wear-resistant layer of a wear-resistant material is formed on the outer periphery of the base material, and a familiar layer is laminated on the outer layer of the wear-resistant layer to have a sliding surface formed flush with each other.
A piston ring provided with a wear identification material made of a member different from the base material on the outer peripheral surface of the base material.
The piston ring according to claim 1, wherein the wear identification material has a top flush with the sliding surface.
The piston ring according to claim 1, wherein the wear identification material has a top covered with the familiar layer.
The piston ring according to any one of claims 1 to 3, wherein a wear identification material made of a member different from the wear resistant layer and the familiar layer is embedded in the wear resistant layer and / or the familiar layer.
The piston ring according to any one of claims 1 to 4, wherein the wear identification material has a shape representing characters or figures when viewed from the outer peripheral side of the sliding surface.
A wear-resistant layer of a wear-resistant material is formed on the outer periphery of the base material, and a familiar layer is laminated on the outer layer of the wear-resistant layer to have a sliding surface formed flush with each other.
A piston ring provided with a wear identification recess on the outer peripheral surface of the base material.
The piston ring according to claim 6, wherein a wear identification material made of a member different from the base material is fitted in the wear identification recess.
The piston ring according to claim 6 or 7, wherein the wear identification recess is covered with the wear resistant layer and / or the familiar layer.
The piston ring according to any one of claims 6 to 8, wherein the wear identification recess has a shape representing a character or a figure when viewed from the outer peripheral side of the sliding surface.
The piston ring according to any one of claims 6 to 9, wherein a wear identification material made of a member different from the wear resistant layer and the familiar layer is embedded in the wear resistant layer and / or the familiar layer.
A piston ring made of a ring-shaped base material.
A wear identification recess is provided on the outer peripheral portion of the base material.
A piston ring in which the outer peripheral surface of the base material is covered with a wear-resistant layer of a wear-resistant material, and the surface of the wear-resistant layer is a sliding surface.
The piston ring according to claim 11, wherein the wear identification recess is provided from the outer peripheral surface of the base material to a certain depth.
The piston ring according to claim 11 or 12, wherein a wear identification material made of a member different from the base material is fitted in the wear identification recess.
The piston ring according to claim 13, wherein the top of the wear identification material is flush with the outer peripheral surface of the base material.
The piston ring according to claim 13, wherein a second wear identification material made of a member different from the wear resistant layer is embedded in the wear resistant layer.
The piston ring according to claim 15, wherein the wear identification material and the second wear identification material are formed as an integral member.
The piston ring according to claim 15, wherein the wear identification material and the second wear identification material are formed as separate members.
A piston ring made of a ring-shaped base material.
The outer peripheral surface of the base material is covered with the wear-resistant layer of the wear-resistant material, and the surface of the wear-resistant layer is a sliding surface.
A piston ring provided with a wear identification recess on the outer peripheral portion of the wear resistant layer.
The piston ring according to any one of claims 11 to 18, wherein the wear identification recess has a shape representing a character or a figure when viewed from the outer peripheral side of the sliding surface.
A piston ring made of a ring-shaped base material.
The outer peripheral surface of the base material is covered with the wear-resistant layer of the wear-resistant material, and the surface of the wear-resistant layer is a sliding surface.
A piston ring in which a wear identification material made of a member different from the wear-resistant layer is embedded in the wear-resistant layer.
The piston ring according to any one of claims 13 to 17, 20 in which the wear identification material has a shape representing characters or figures when viewed from the outer peripheral side of the sliding surface.