Compression ring with semi-inlaid high-wear-resistant coating

Abstract

The compression ring is arranged in a cylinder body and comprises an upper end face, a lower end face and an outer circle side face, the compression ring comprises a coating and a base body, an inlay belt is arranged at the bottom of the outer circle side face of the base body to form a semi-inlay groove, and the coating is located in the semi-inlay groove and is in smooth transition with the inlay belt. The profile of the formed outer circle side surface is an asymmetric barrel surface; the coating is a PVD or DLC coating. The piston ring is provided with the PVD / DLC coating with the sharp corner at the lower edge of the outer circle, so that the wear resistance and the better sealing function can be met at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of piston rings for internal combustion engines, in particular to a semi-embedded high-wear-resistant coating compression ring. Background Art

[0002] As a typical existing piston ring assembly, it is well known in the industry that it is composed of a first compression ring, a second compression ring and an oil control ring. The main function of the first compression ring is to seal the high-pressure fuel gas in the combustion chamber. Otherwise, the downward leakage of fuel gas will cause power loss of the engine and accelerate the deterioration of the engine oil, greatly reducing the performance of the entire machine.

[0003] Basically, various characteristics of the first compression ring have an impact on its sealing performance, such as material stability, coating wear resistance, closed gap size, axial height / side clearance size, radial thickness / back clearance size, elastic force / surface pressure value, etc. In addition, a large number of simulation calculations and actual engine bench tests have shown that the size of the lower edge of the outer circle of the first compression ring has an important influence on the sealing performance. In other words, the sharper the lower edge of the outer circle, the better the sealing performance, and the larger the chamfer or fillet of the lower edge of the outer circle, the worse the sealing performance. This has become a consensus in the piston ring industry. Obviously, keeping the lower edge of the outer circle sharp is the best choice.

[0004] Therefore, the semi-inlaid structure of the first compression ring outer circle coating has been widely used, including semi-inlaid electroplating coating and semi-inlaid molybdenum spray coating, which has formed a standard design, which not only obtains the required outer circle wear-resistant coating, but also obtains the required outer circle sharp lower edge.

[0005] PVD or DLC (Diamond-Like Carbon) coatings are used on piston rings due to their excellent friction and wear properties, but on the other hand, their high coating stress makes them very brittle, especially on the edges of the piston rings where coating chipping is prone to occur. If the edges chip when the engine is working, it will cause cylinder damage. Therefore, compression rings with PVD / DLC coatings must keep the outer edges rounded, such as R0.3mm or R0.25mm.

[0006] However, technicians hope to use PVD / DLC coated piston rings with sharp corners on the lower edge of the outer circle on engines with higher performance requirements, so as to meet both wear resistance and better sealing function. Utility Model Content

[0007] Purpose of the utility model: In order to overcome the shortcomings of the background technology, the utility model seeks to protect a semi-inlaid high wear-resistant coating compression ring, a ring with a PVD or DLC coating, while maintaining the sharp corners of the lower edge of the outer circle.

[0008] Technical solution: The semi-inlaid high wear-resistant coating compression ring disclosed by the utility model is placed in the cylinder body, including an upper end face, a lower end face and an outer circular side face. The compression ring includes a coating and a substrate. The outer circular side face of the substrate is provided with an inlaid band at the bottom to form a semi-inlaid groove. The coating is located in the semi-inlaid groove and smoothly transitions with the inlaid band. The outer circular side face profile formed is an asymmetric barrel surface.

[0009] The coating is a PVD or DLC coating.

[0010] Furthermore, the compression ring is suitable for cylinder diameters of 40-300 mm, particularly 100-150 mm.

[0011] Furthermore, the compression ring has a ring height of 1.5-4.5 mm, particularly 2.5-4.0 mm.

[0012] Furthermore, when PVD coating is used, the coating thickness is t=0.025-0.05mm and the coating hardness is HV1200 0.05 -HV1800 0.05 ;

[0013] When using DLC ​​coating, the coating thickness is t=0.01-0.04mm and the coating hardness is HV2000 0.025 -HV3500 0.025 .

[0014] 10. Furthermore, the angle between the side surface and the end surface of the semi-inlaid groove is 50-60°, and the side surface is connected to the groove bottom plane through a fillet, and the arc radius of the fillet is Ry=R0.15-0.35mm.

[0015] Furthermore, the inlaid band width h1=0.05-0.45 mm.

[0016] Furthermore, the upper edge radius of the semi-inlaid groove is Rx=R0.25-0.45mm.

[0017] Furthermore, the axial height of the rounded corner of the upper edge of the outer circular side surface is h2=0.3max when the ring height is ≤3.0mm; or h2=0.4max when the ring height is >3.0mm; the lower edge of the outer circular side surface maintains a sharp angle.

[0018] Furthermore, the upper end surface and the lower end surface are parallel or non-parallel.

[0019] Beneficial effects: Compared with the prior art, the utility model has the advantages that the piston ring has a PVD / DLC coating with sharp corners on the lower edge of the outer circle, which can simultaneously meet the requirements of wear resistance and better sealing function. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the radial local structure of the utility model. DETAILED DESCRIPTION

[0021] like Figure 1 The semi-inlaid high wear-resistant coating compression ring shown is suitable for cylinder diameters of 40-300 mm, particularly 100-150 mm, and has a ring height of 1.5-4.5 mm, particularly 2.5-4.0 mm.

[0022] The compression ring is placed in the cylinder body and comprises an upper end surface, a lower end surface and an outer circular side surface.

[0023] The compression ring includes a coating 1 and a substrate 2. The outer circular side surface of the substrate 2 is provided with an inlay band 3 at the bottom to form a semi-inlay groove. The coating 1 is located in the semi-inlay groove and smoothly transitions with the inlay band 3. The outer circular side surface profile formed is an asymmetric barrel surface in accordance with the well-known standards in the piston ring industry.

[0024] The outer circle profile of the asymmetric barrel surface is adopted. Firstly, it can conform to the outer circle wear law better than the symmetrical barrel surface and thus has better friction and wear performance. Secondly, it has better post-coating processing technology than the symmetrical barrel surface.

[0025] The material of the substrate 2 is steel or nitrided steel, or ductile iron.

[0026] The coating 1 is a PVD (CrN) or DLC (Diamond-Like Carbon) coating.

[0027] When PVD coating is used, the coating thickness t is 0.015-0.07mm, preferably 0.025-0.050mm, and the coating hardness is HV1200 0.05 -HV1800 0.05 ;

[0028] When DLC coating is used, the coating thickness is t=0.01-0.04mm, preferably 0.015-0.025mm, and the coating hardness is HV2000 0.025 -HV3500 0.025 .

[0029] The angle between the side surface and the end surface of the semi-inlaid groove is 50-60°, and the side surface is connected to the groove bottom plane through a fillet, and the arc radius of the fillet Ry=R0.15-0.35mm, so that the part appears relatively flat, which is conducive to preventing stress concentration.

[0030] The inlaid band 3 has a width h1 of 0.05-0.45 mm.

[0031] The upper edge radius of the semi-inlaid groove is Rx=R0.25-0.45mm.

[0032] The axial height of the rounded corners on the outer circular side surface is h2=0.3max, when the ring height is ≤3.0mm;

[0033] Or h2=0.4max, when the ring height is>3.0mm;

[0034] The lower edge of the outer circular side surface maintains a sharp angle and has no burrs.

[0035] The semi-inlaid high wear-resistant coating compression ring described in the present application has an upper end face and a lower end face that are parallel or non-parallel, such as rectangular, wedge-shaped or trapezoidal.

[0036]

[0037] The effects of this application are compared with the existing technology, as shown in the table above.

Claims

1. A semi-inlaid high wear-resistant coating compression ring, the compression ring is placed in a cylinder body, including an upper end face, a lower end face and an outer circular side face, characterized in that: The compression ring comprises a coating (1) and a base (2); an outer circular side surface of the base (2) is provided with an inlay band (3) at the bottom to form a semi-inlay groove; the coating (1) is located in the semi-inlay groove and smoothly transitions with the inlay band (3); the outer circular side surface profile formed is an asymmetric barrel surface; The coating (1) is a PVD or DLC coating.

2. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The compression ring is suitable for cylinder diameters of 40-300 mm.

3. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The compression ring has a height of 1.5-4.5 mm.

4. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: When PVD coating is used, the coating thickness is t=0.025-0.05mm and the coating hardness is HV1200 0.05 -HV1800 0.05 ; When using DLC ​​coating, the coating thickness is t=0.01-0.04mm and the coating hardness is HV2000 0.025 -HV3500 0.025 .

5. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The angle between the side surface and the end surface of the semi-inlaid groove is 50-60°, and the side surface is connected to the groove bottom plane through a fillet, and the arc radius of the fillet is Ry=R0.15-0.35mm.

6. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The inlaid band (3) has a width h1 of 0.05-0.45 mm.

7. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The upper edge radius of the semi-inlaid groove is Rx=R0.25-0.45mm.

8. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The axial height of the rounded corner of the upper edge of the outer circular side surface is h2=0.3max when the ring height is ≤3.0mm; or h2=0.4max when the ring height is >3.0mm; the lower edge of the outer circular side surface maintains a sharp angle.

9. The semi-inlaid high wear-resistant coating compression ring according to claim 1, characterized in that: The upper end surface and the lower end surface are parallel or non-parallel.

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