Engine and cylinder liner

Abstract

The application relates to the technical field of engines, and discloses an engine and a cylinder sleeve, which comprise a cylinder sleeve body, the inner wall of the cylinder sleeve body is sequentially divided into a first region, a second region and a third region, at least the first region and / or the second region are provided with a plurality of concave points, the depth of the concave points in the first region is a first preset depth, the arrangement area rate is a first preset area rate, the depth of the concave points in the second region is a second preset depth, the arrangement area rate is a second preset area rate, the first preset depth is greater than the second preset depth, and the first preset area rate is smaller than the second preset area rate. The engine and the cylinder sleeve provided by the application can improve the lean oil state, change the boundary lubrication into mixed lubrication by adopting the concave points with the larger depth and the lower distribution density in the first region, can reduce the contact area, reduce the oil film thickness, reduce the friction coefficient under the dynamic pressure lubrication state, and further reduce the oil consumption by adopting the concave points with the smaller depth and the higher distribution density in the second region.

Description

An engine and cylinder liner Technical Field

[0001] This invention relates to the field of engine technology, and more specifically, to an engine and cylinder liner. Background Technology

[0002] The engine is a crucial component of a car, consisting of cylinder liners and pistons housed within them. The pistons reciprocate within the cylinder block of the cylinder liner. The surface structure of the inner wall of the cylinder liner directly affects the wear resistance, lubrication, and friction reduction properties of the engine.

[0003] With increasingly stringent environmental policies, engine emission requirements are becoming more and more demanding. As a crucial engine component, the cylinder liner must help the entire engine meet these requirements. However, the properties of the cylinder wall surface structure can lead to increased fuel consumption and unstable air leakage, making it impossible for the engine to meet the new emission standards.

[0004] In summary, how to effectively solve the problems of increased engine oil consumption and unstable air leakage caused by insufficient performance of the engine's inner wall surface is a problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an engine and cylinder liner that can effectively solve the problems of increased engine oil consumption and unstable air leakage caused by insufficient performance of the engine inner wall surface.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A cylinder liner includes a cylinder liner body, the inner wall of which is sequentially divided into a first region, a second region, and a third region. At least the first region and / or the second region are provided with a plurality of recesses. The depth of the recesses in the first region is a first preset depth, and the arrangement area ratio is a first preset area ratio. The depth of the recesses in the second region is a second preset depth, and the arrangement area ratio is a second preset area ratio. The first preset depth is greater than the second preset depth, and the first preset area ratio is less than the second preset area ratio.

[0008] Optionally, in the above-mentioned cylinder liner, the range of the first preset area ratio is 1% to 30%, and the range of the second preset area ratio is 10% to 50%.

[0009] Optionally, in the above-mentioned cylinder liner, the first preset depth ranges from 3 to 10 μm, and the second preset depth ranges from 1 to 8 μm.

[0010] Optionally, in the above-mentioned cylinder liner, the maximum oil storage volume of each of the aforementioned recesses is 0.006 mm.3 .

[0011] Optionally, in the above-mentioned cylinder liner, the cross-sectional area of ​​each of the concave points is not greater than 0.6 mm. 2 .

[0012] Optionally, in the above-mentioned cylinder liner, the third region is provided with the concave point, and the depth of the concave point in the third region is the first preset depth, and the arrangement area ratio is the first preset area ratio.

[0013] Optionally, in the above-mentioned cylinder liner, the plurality of the concave points are distributed in multiple rows along the circumferential direction of the inner wall of the cylinder liner body, and in multiple columns along the axial direction of the inner wall of the cylinder liner body. The concave points in each adjacent two rows are staggered along the axial direction, and the concave points in each adjacent two columns are staggered along the circumferential direction.

[0014] Optionally, in the above-mentioned cylinder liner, the length of the first region satisfies the following formula:

[0015] Ⅰ = L2 + aL1 + b(L - L2 + H)

[0016] In the formula, Ⅰ is the length of the first region, L is the stroke of the piston, L1 is the height of the fire shore, L2 is the distance from the uppermost end to the lowermost end of each annular groove of the piston, H is the height of the first annular groove, and a and b are both coefficients, and 0.1 < a < 0.5, b < 0.1.

[0017] The starting point of the first region is a preset distance above the firepower shore height of the piston when the piston reaches the top dead center. The preset distance d = (1-a)L1, where d is the preset distance.

[0018] The boundary between the second region and the third region is the position of the first annular groove of the piston when the piston reaches the bottom dead center.

[0019] The termination point of the third region is the lower end face of the cylinder liner.

[0020] Optionally, in the above-mentioned cylinder liner, the inner wall of the cylinder liner body is provided with a basic mesh pattern, and the average peak-valley height of the basic mesh pattern ranges from 1 to 4.5 μm, the average peak spacing ranges from 20 to 52 μm, and the axial included angle of the basic mesh pattern is greater than 135°.

[0021] The cylinder liner provided by the present invention includes a cylinder liner body. The inner wall of the cylinder liner body is divided into a first region, a second region and a third region in sequence. At least the first region and / or the second region are provided with a plurality of recesses. The depth of the recesses in the first region is a first preset depth and the arrangement area ratio is a first preset area ratio. The depth of the recesses in the second region is a second preset depth and the arrangement area ratio is a second preset area ratio. The first preset depth is greater than the second preset depth and the first preset area ratio is less than the second preset area ratio.

[0022] The cylinder liner provided by this invention divides the inner wall of the cylinder liner body into a first region, a second region, and a third region according to the operating state of the piston ring assembly. By providing multiple concave points in at least the first region and / or the second region, and by using deeper and less densely distributed concave points in the first region, the oil-deficient state can be improved, and boundary lubrication can be changed to mixed lubrication. The second region uses shallower and denser concave points, which reduces the contact area, reduces the oil film thickness, and reduces the friction coefficient under hydrodynamic lubrication, thereby reducing oil consumption.

[0023] To achieve the above objectives, the present invention also provides an engine comprising any of the aforementioned cylinder liners. Since the cylinder liners described above possess the aforementioned technical effects, the engine having the cylinder liner should also possess the corresponding technical effects. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 is a schematic diagram of the partitioning of a cylinder liner according to a specific embodiment of the present invention;

[0026] Figure 2 is a schematic diagram of a concave dot arrangement;

[0027] Figure 3 is a cross-sectional view of the cylinder liner concave point corresponding to Figure 2;

[0028] Figure 4 shows another schematic diagram of the concave dot arrangement;

[0029] Figure 5 is a cross-sectional schematic diagram of the cylinder liner concave point corresponding to Figure 4.

[0030] The following labels are shown in the attached diagram:

[0031] Zone 1: 100; Zone 2: 200; Zone 3: 300.

[0032] Cylinder liner body 1, concave point 11, piston 2. Detailed Implementation

[0033] This invention discloses an engine and cylinder liner to improve the performance of the engine's inner wall surface, thereby reducing engine oil consumption and air leakage.

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Please refer to Figure 1, which is a schematic diagram of the partitioning of a cylinder liner according to a specific embodiment of the present invention.

[0036] In one embodiment, the cylinder liner provided by the present invention includes a cylinder liner body 1. The inner wall of the cylinder liner body 1 is sequentially divided into a first region 100, a second region 200, and a third region 300. At least the first region 100 and / or the second region 200 are provided with a plurality of recesses 11. That is, recesses 11 can be provided in the first region 100, the second region 200, and the third region 300; or recesses 11 can be provided in the first region 100 and the second region 200, but not in the third region 300; or recesses 11 can be provided in the second region 200, but not in the first region 100 and the third region 300; or recesses 11 can be provided in the first region 100, but not in the second region 200 and the third region 300. No recesses 11 are provided in the portion above the first region 100. The depth of the concave points 11 in the first region 100 is a first preset depth, and the distribution area ratio is a first preset area ratio. The depth of the concave points 11 in the second region 200 is a second preset depth, and the distribution area ratio is a second preset area ratio. The first preset depth is greater than the second preset depth, and the first preset area ratio is less than the second preset area ratio. It should be noted that the distribution area ratio, also known as the loss area ratio, refers to the ratio of the total lost area corresponding to each concave point 11 on the inner wall to the total surface area of ​​the corresponding inner wall. That is, the concave points 11 in the first region 100 have a larger depth and a sparser distribution density, while the concave points 11 in the second region 200 have a smaller depth and a denser distribution density. The inner wall surface texture of the cylinder liner body 1 is relatively smooth, with low frictional resistance. At the same time, the shallow grooves and low oil storage effectively reduce friction and oil consumption. The concave points 11 allow the lubricating oil to better adhere to the concave points 11, enabling the lubricating oil to be flexibly stretched when the object moves. The smooth platform surface around the oil storage concave points 11 also serves as a support for the stretching of the lubricating oil, thus forming a fluid dynamic lubricating oil film layer. Therefore, by dividing the piston ring assembly into a first region 100, a second region 200, and a third region 300 according to the operating state of the piston ring assembly, and by providing multiple recesses 11 in at least the first region 100 and / or the second region 200, the wear resistance and lubrication requirements of the piston 2 when it operates to different positions can be taken into account.

[0037] The cylinder liner provided by this invention divides the inner wall of the cylinder liner body 1 into a first region 100, a second region 200, and a third region 300 according to the operating state of the piston ring assembly. By providing multiple recesses 11 in at least the first region 100 and / or the second region 200, and by using recesses 11 with greater depth and sparser distribution density in the first region 100, the lean oil condition can be improved, and boundary lubrication can be changed to mixed lubrication. The second region 200 uses recesses 11 with smaller depth and denser distribution density, which reduces the contact area, reduces the oil film thickness, reduces the friction coefficient under hydrodynamic lubrication, and thus reduces oil consumption.

[0038] In one embodiment, the cross-sectional area of ​​a single concave point 11 in the second region 200 is not less than the cross-sectional area of ​​a single concave point 11 in the first region 100. That is, the cross-sectional area of ​​the concave point 11 in the first region 100 is smaller to improve the oil-deficient state, while the cross-sectional area of ​​the concave point 11 in the second region 200 is larger to reduce the contact area, reduce the oil film thickness, and reduce the coefficient of friction under hydrodynamic lubrication.

[0039] In one embodiment, the first preset area ratio ranges from 1% to 30%, and the second preset area ratio ranges from 10% to 50%. That is, the distribution density of the concave dots 11 in the first region 100 is relatively sparse, while the distribution density of the concave dots 11 in the second region 200 is relatively dense.

[0040] In one embodiment, the first preset depth ranges from 3 to 10 μm, and the second preset depth ranges from 1 to 8 μm. That is, the depth of the concave point 11 in the first region 100 is larger, and the depth of the concave point 11 in the second region 200 is smaller.

[0041] In one embodiment, the maximum oil storage volume of each concave point 11 is 0.006 mm. 3 The size of the concave point 11 can be controlled by setting the maximum oil storage volume of the concave point 11.

[0042] In one embodiment, the cross-sectional area of ​​each concave point 11 is no greater than 0.6 mm. 2 In this application, the shape of the concave point 11 is not specifically limited; the cross-section of the concave point 11 can be circular, polygonal, etc. The size of the concave point 11 can be controlled by setting the cross-sectional area of ​​the concave point 11.

[0043] In one embodiment, the third region 300 is provided with recesses 11, and the depth of the recesses 11 in the third region 300 is a first preset depth, and the area ratio is a first preset area ratio. The third region 300 adopts the same recesses 11 as the first region 100 to achieve a similar effect.

[0044] In some embodiments, referring to FIGS. 2, 3, 4, and 5, multiple indentations 11 are circumferentially distributed in multiple rows along the inner wall of the cylinder liner body and axially distributed in multiple columns along the inner wall of the cylinder liner body. The indentations 11 in each adjacent two rows are axially staggered, and the indentations 11 in each adjacent two columns are circumferentially staggered. The indentations 11 are arranged in multiple rows and multiple columns. The indentations 11 in each row are arranged along the circumference, and the indentations 11 in each column are arranged axially. The indentations 11 are arranged in a spiral pattern as a whole, such that the indentations 11 in the (n + 1)-th layer are located between the adjacent two indentations 11 in the n-th layer in a "pin" shape distribution, that is, the indentations 11 in each adjacent two rows are axially staggered, and the indentations 11 in each adjacent two columns are circumferentially staggered, making each indentation 11 relatively independently enclosed. The above arrangement of the indentations 11 can maximize the number of indentations 11 and the area ratio, reduce the contact area with the piston ring, that is, reduce the friction area of the piston ring, thereby reducing friction; when mating with the piston ring, the lubrication is uniform, avoiding problems such as piston ring gas leakage and piston ring wear.

[0045] In one embodiment, the length of the first region 100 satisfies the following formula:

[0046] Ⅰ = L2 + aL1 + b(L - L2 + H)

[0047] In the formula, Ⅰ is the length of the first region 100, L is the stroke of the piston 2, L1 is the height of the fire deck, L2 is the distance from the uppermost end to the lowermost end of each ring groove of the piston 2, and a and b are both coefficients, and 0.1 < a < 0.5, b < 0.1;

[0048] The starting point of the first region 100 is a preset distance above the height of the fire deck of the piston 2 when the piston 2 runs to the top dead center. The preset distance d = (1 - a)L1. In the formula, d is the preset distance, and a and L1 have the same meanings as those in the above formula for calculating the length of the first region; the demarcation between the second region 200 and the third region 300 is the position corresponding to the first ring groove of the piston 2 when the piston 2 runs to the bottom dead center; the termination point of the third region 300 is the lower end face of the cylinder liner.

[0049] Referring to FIG. 1, the first region 100 is located above the stroke center C, and the stroke center C is the central position of the standard stroke M. The starting point of the standard stroke M is the position corresponding to the oil ring groove when the piston 2 runs to the top dead center; the termination point of the standard stroke M is the position corresponding to the first ring groove when the piston 2 runs to the bottom dead center;

[0050] That is, M = L - L2 + H

[0051] In the formula, L is the stroke of the piston 2, L2 is the distance from the uppermost end to the lowermost end of each ring groove of the piston 2, that is, the distance from the uppermost end of the first ring groove to the lowermost end of the last ring groove, and H is the height of the first ring groove;

[0052] The starting point of the first region 100 is located at a distance of (1-a)L1 above the height of the piston 2's firing position when the piston 2 reaches top dead center. The length I of the first region 100 satisfies I = L2 + aL1 + bM = L2 + aL1 + b(L - L2 + H). Based on the starting point and length of the first region 100, the ending point of the first region 100 can be obtained. The starting point of the second region 200 is the ending point of the first region 100, and the ending point of the second region 200 is the starting point of the third region 300, which is also the dividing point between the two. Specifically, it is the position corresponding to the first annular groove of the piston 2 when the piston 2 reaches bottom dead center. The ending point of the third region 300 is located on the lower end face of the cylinder liner.

[0053] The area above the first region 100 is the fire support area of ​​piston 2. Since the piston rings cannot reach this area, they will not experience wear. Therefore, considering usage and manufacturing costs, no recess 11 is provided above the first region 100. The first region 100, the second region 200, and the third region 300 are divided as described above, and the same or different recesses 11 are provided on the three regions. This allows for different friction and lubrication at different positions of the piston 2's sliding stroke, depending on the piston 2's operating state. This maximizes the improvement of the sliding performance of the cylinder bore inner surface, ensures uniform oil storage on the surface, improves the wear resistance of the cylinder liner and piston ring pair, and simultaneously reduces friction and oil consumption.

[0054] Furthermore, the second region 200 is provided with large, shallow, and densely packed depressions 11, with the area ratio of the depressions 11 being 10%-50%, and the oil storage volume of a single depression 11 being 0.00015-0.0048 mm. 3 The depth of concave point 11 is 1-8μm, and the cross-sectional area of ​​a single concave point 11 is 0.15-0.6mm². 2 The first region 100 and the third region 300 are provided with small, deep, and sparsely distributed concave points 11. The area ratio of the concave points 11 is 1%-30%, and the oil storage volume of a single concave point 11 is 0.00045-0.006 mm. 3 The depth of concave point 11 is 3-10μm.

[0055] In one embodiment, the inner wall of the cylinder liner body is provided with a basic mesh pattern, and the average peak-valley height Rz of the basic mesh pattern ranges from 1 to 4.5 μm, the average peak spacing S ranges from 20 to 52 μm, and the axial angle of the basic mesh pattern is greater than 135°. This basic mesh pattern is a smooth mirror-like pattern; the smoother the basic mesh pattern, the lower the frictional resistance. Simultaneously, the shallower the grooves, the less oil is stored, resulting in a more significant effect in reducing friction and oil consumption. Based on the setting of the concave point 11, when the basic mesh pattern of the inner wall is configured as described above, it can better cooperate with the concave point 11 to achieve good friction reduction and lubrication effects.

[0056] In one embodiment, the inner wall surface is polygonal, with the roundness of 3-6 edges not exceeding 3.5 μm, 7-9 edges not exceeding 1 μm, and 10-20 edges not exceeding 0.35 μm. The cylindricity of the inner surface is not exceeding 0.008 mm. Before machining the concave point 11, the base surface is machined into an approximately standard circle. However, due to the superposition of machining processes, irregular vibrations and undulations appear on the inner surface circumference. To effectively evaluate this irregularity, it is called polygonal, which is the roundness magnified and subdivided into multiple undulations. The roundness error limit value of the undulation (UPR) value range of each circumference is calculated using the attenuation function of EQ1. By limiting the parameters of the polygonal shape as described above, the more precise the control of the base surface shape, the better it is for the lubrication effect and airtightness of the engine during operation.

[0057] The cylinder liners in the above embodiments can be manufactured by pre-dimpling processing, dimple forming processing, and dimple post-processing, specifically including the following steps:

[0058] S1: Pre-drilling of the concave points involves using high-precision machine tools to perform contouring and shaping of the inner and outer diameters of the cylinder liner blank. The specific process flow is roughing, semi-finishing, finishing, pre-honing of the inner hole, and final honing of the inner hole. Before the concave point machining, the entire surface of the cylinder liner inner wall is pre-honed and final honed to meet the requirements for inner hole cylindricity, polygonal shape, and basic texture parameters.

[0059] S2: Concave forming process. The cylinder liner obtained in step S1 is placed with the large opening facing down on the equipment positioning seat. Multiple concave points are formed by gasification impact on the inner wall of the cylinder liner through laser etching, shot blasting with angular abrasive particles, and abrasive gas jet.

[0060] Specifically, the dimples are arranged in a spiral pattern. During the processing, an air blowing device is added to blow air synchronously to ensure that no metal residue remains at the bottom of the dimples.

[0061] S3: Post-treatment of pits: Use polishing abrasive strips and other equipment to polish the entire cylinder bore, removing residual slag around the pits on the inner wall. Ensure that the surface roughness Rpk at the peak of the inner surface texture is ≤0.15μm.

[0062] Multiple indentations are formed on the inner wall of the cylinder liner by aerosol impact through laser etching, shot blasting with angular abrasive particles, and abrasive gas jet. The indentation structure on the inner wall is uniform, with consistent groove depth and high stability.

[0063] To more clearly illustrate the effects of setting concave dots in different areas of the above embodiments, several specific embodiments are described below.

[0064] Example 1

[0065] In Example 1, the first region is the low-speed piston operating zone, starting above the piston's firing position and 10mm from the top of the cylinder liner support shoulder, with a total length of 30mm. The second region is the high-speed piston operating zone, with a total length of 103mm. The third region is the low-speed piston operating zone, starting at the end point of the second region and ending at the lower end face of the cylinder liner, with a total length of 65mm. Recessed points are provided in the first, second, and third regions, except for the portion of the first region above the starting point.

[0066] The starting point of the first region is near the height of the piston fire shore, upwards, that is, at a preset distance above the height of the piston fire shore. The preset distance is (1-a)L1=10.2, and the result is rounded up.

[0067] The length of the first region Ⅰ = L2 + aL1 + bM = L2 + aL1 + b(L - L2 + H) = 25 + 0.32 15 = 29.8, round the result, where L2 = 25, a = 0.32, b = 0, L = 125, L1 = 15, H = 2.5. M = L - L2 + H = 125 - 25 + 2.5 = 102.5, round the result.

[0068] The concave dots on the inner wall are distributed in a staggered spiral pattern, with the cross-sectional area of ​​a single concave dot in the first region being 0.15 mm². 2 The oil storage volume of a single concave point is 0.0006-0.0012 mm. 3 The depth is 4-8 μm, and the area ratio of the concave dots is 1.5%; the cross-sectional area of ​​a single concave dot in the second region is 0.15 mm². 2 The oil storage volume of a single concave point is 0.000225-0.00045 mm. 3 The depth of the concave dots is 1.5-3.0 μm, and the area ratio of the concave dots is 12%. The density and arrangement of the concave dots in the third region are the same as those in the first region. No concave dots are set on the part above the starting point of the first region. The basic texture parameters of the cylinder liner inner wall are: average peak-valley height Rz=3.52μm, average peak spacing S=38μm, and the axial angle of the mesh is 150°, so that the entire inner wall surface has a uniform texture.

[0069] The cylinder liner described above is prepared according to the following steps:

[0070] Before the concave point machining, high-precision machine tools are used to perform contouring and shaping of the inner hole and outer circle of the cylinder liner blank. The specific process flow is roughing, semi-finishing, finishing, pre-honing of the inner hole, and final honing of the inner hole. Before the concave point machining, the entire surface of the cylinder liner inner wall is pre-honed and final honed to achieve an inner surface cylindricity of 0.005mm, and a multi-faceted inner hole: 3-6 edges no greater than 3μm, 7-9 edges no greater than 0.8μm, and 10-20 edges no greater than 0.3μm; as well as basic texture parameter requirements.

[0071] For the concave point forming process, place the cylinder liner obtained from the above steps with the large end facing down on the positioning seat of the laser equipment, and use the laser to vaporize and impact the inner wall of the cylinder liner to perform concave point machining from top to bottom. Specific laser parameters: use a fiber laser, power: 50W, frequency: 50KHz, focal length: 5mm. The multiple concave points are arranged in multiple rows and columns. The concave points in each row are arranged along the circumference, and the concave points in each column are arranged along the axis. The concave points in adjacent rows and adjacent columns are all offset. The concave points in every other row are circumferentially aligned, and the concave points in every other column are radially aligned. The concave points are arranged in a spiral pattern as a whole, so that the concave points in the (n + 1)-th layer are located between two adjacent concave points in the n-th layer in a "pin" shape, making each concave point relatively independent and enclosed, thereby reducing the contact area between the piston ring and the cylinder wall surface and achieving the effect of reducing friction and fuel consumption. During the laser engraving process, a blowing device is added to blow air synchronously to ensure that there is no metal residue remaining at the bottom of the formed micro-pits.

[0072] For the post-treatment of the concave points, use a sponge abrasive strip to polish the entire cylinder bore to remove the residual scum around the laser concave points on the inner wall. The polishing reaches an inner surface peak roughness Rpk: 0.06 - 0.12μm.

[0073] Example 2

[0074] In Example 2, the starting point is at a position above the piston fire deck height, 8mm above the upper surface of the cylinder liner support shoulder, and the overall length is 24mm; the overall length of the second region is 151mm; the starting point of the third region is at the termination point of the second region, and the termination point is to the lower end face of the cylinder liner, with an overall length of 66mm. Among them, concave points are set in the first region and the second region, and no concave points are set in the upward part of the starting point of the first region and the third region.

[0075] The starting point of the first region is a preset distance upward from the piston fire deck height. The specific preset distance (1 - a)L1 = 7.5, and the result is rounded; the length I of the first region = L2 + aL1 + bM = L2 + aL1 + b(L - L2 + H) = 19.5 + 0.25 10 + 0.01 (170 - 19.5 + 3) = 23.535, and the result is rounded; where L2 = 19.5, a = 0.25, b = 0.01, L = 170, L1 = 10, H = 3. M = L - L2 + H = 170 - 19.5 + 3 = 153.5, and the result is rounded;

[0076] The concave points on the inner wall surface adopt offset spiral lines respectively. The cross-sectional area of a single concave point in the first region is 0.1mm 2 , the oil storage volume of a single concave point is 0.0004 - 0.0008mm 3 , the depth is 4 - 8μm, and the arrangement area ratio of the concave points is 1.8%; the cross-sectional area of a single concave point in the second region is 0.2mm2 The oil storage volume of a single concave point is 0.00028-0.00056 mm. 3 The depth is 1.4-2.8μm, and the area ratio of the concave dots is 17%; no concave dots are set on the part upward from the starting point of the first region and the third region. The basic texture parameters of the cylinder liner inner wall are: average peak-valley height Rz=2.8μm, average peak spacing S=32μm, and the axial angle of the mesh is 155°, so that the entire inner wall surface has a uniform texture.

[0077] The preparation method of the cylinder liner, etc. is the same as that of the cylinder liner in Example 1, and will not be repeated here.

[0078] To more clearly illustrate the effect of setting concave dots in different regions of the above embodiments, the following examples 3-6 and comparative examples are compared and explained. In Example 3, concave dots are set in the first, second, and third regions respectively. In Example 4, concave dots are set in the first and second regions respectively, but no concave dots are set in the third region. In Example 5, concave dots are set in the second region, but no concave dots are set in the first and third regions. In Example 6, concave dots are set in the first region, but no concave dots are set in the second and third regions. Furthermore, the division of the first, second, and third regions of the cylinder liner inner wall in Examples 3-6 is the same as the division of the three regions in Example 1 above, and the same preparation method as in Example 1 is used for processing. The obtained cylinder liner inner wall has an average peak-valley height Rz range of 2.8-3.52 μm, an average peak spacing S range of 30-38, and a mesh axial angle of 150°. The specific state of the concave dots on the inner wall is as follows:

[0079] Example 3

[0080] The cross-sectional area of ​​a single concave point in the first and third regions is 0.1 mm. 2 The oil storage volume of a single concave point is 0.00065 mm. 3 The area ratio of the concave dots is 1.8%; the cross-sectional area of ​​a single concave dot in the second region is 0.2 mm². 2 The oil storage volume of a single indentation is 0.0003 mm. 3 The area ratio of the concave dots is 17%.

[0081] Example 4

[0082] The cross-sectional area of ​​a single concave point in the first region is 0.1 mm. 2 The oil storage volume of a single indentation is 0.00065 mm. 3 The area ratio of the concave dots is 1.8%; the cross-sectional area of ​​a single concave dot in the second region is 0.2 mm². 2 The oil storage volume of a single indentation is 0.0003 mm. 3 The area ratio of the concave dots is 17%.

[0083] Example 5

[0084] The cross-sectional area of ​​a single concave point in the second region is 0.2 mm. 2 The oil storage volume of a single indentation is 0.0003 mm. 3 The area ratio of the concave dots is 17%.

[0085] Example 6

[0086] The cross-sectional area of ​​a single concave point in the first region is 0.1 mm. 2 The oil storage volume of a single indentation is 0.00065 mm. 3 The area ratio of the concave dots is 1.8%.

[0087] Comparative Example

[0088] The average peak-valley height Rz of the inner wall basic texture ranges from 5 to 7 μm, and the axial angle of the texture is 135°.

[0089] The cylinder liners in Examples 3 to 6 and the comparative example were tested under the following specific conditions:

[0090] Model: 13L diesel engine; alloy bainitic cylinder liner; steel piston; DLC rings.

[0091] Wear and fuel consumption were tested under full-speed, full-load conditions. Speed: rated speed nt=1800rpm, load: throttle fully open, operating duration: 1000h.

[0092] The backward dragging experiment measures the backward dragging work (friction work). The speed is: using frequency conversion control, with no fuel supply from the engine, the backward dragging device drags the engine to operate stably at any speed between 150-7200 r / min.

[0093] Power: 30-110kw;

[0094] Analog output: 4-20mA torque output;

[0095] Installation: The dynamometer, reverse motor, and dynamometer end support must be arranged on the same iron base plate. The torque meter is placed between the reverse motor and the overrunning clutch.

[0096] The comparison of frictional work, wear amount and fuel consumption obtained from the experiment is shown in Table 1.

[0097] Table 1 Comparison of test results of Examples 3-6 and comparative examples

[0098]

[0099] As can be seen, using the friction work tested by the conventional mesh cylinder liner as standard 1, the friction work of the cylinder liners in Examples 3 to 6 all decreased; using the wear amount tested by the conventional mesh cylinder liner as standard 1, the wear amount of the cylinder liners in Examples 3 to 6 all decreased, and the wear amount decreased the most in Example 3; using the oil consumption tested by the conventional mesh cylinder liner as standard 1, the oil consumption of the cylinder liners in Examples 3 to 6 also decreased.

[0100] Based on the cylinder liners provided in the above embodiments, the present invention also provides an engine comprising any one of the cylinder liners described in the above embodiments. Since this engine uses the cylinder liners described in the above embodiments, the beneficial effects of this engine are explained in the above embodiments.

[0101] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0102] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cylinder liner, characterized in that, The cylinder liner body includes an inner wall that is sequentially divided into a first region, a second region, and a third region. At least the first region and / or the second region has multiple recesses. The depth of the recesses in the first region is a first preset depth, and the area ratio of their arrangement is a first preset area ratio. The depth of the recesses in the second region is a second preset depth, and the area ratio of their arrangement is a second preset area ratio. The first preset depth is greater than the second preset depth, and the first preset area ratio is less than the second preset area ratio. The first region is located above the stroke center, and the length of the first region satisfies the following formula: Ⅰ = L2 + aL1 + b(L - L2 + H), where Ⅰ is the length of the first region, L is the piston stroke, L1 is the thrust height, and L2 is the maximum length of each annular groove of the piston. The distance from the top to the bottom, H is the height of the first annular groove, a and b are coefficients, and 0.1 < a < 0.5, b < 0.1; the starting point of the first region is a preset distance above the piston's fire shore height when the piston reaches top dead center, the preset distance d = (1-a)L1, where d is the preset distance; the boundary between the second region and the third region is the position corresponding to the first annular groove of the piston when the piston reaches bottom dead center; the ending point of the third region is the lower end face of the cylinder liner; no concave points are provided above the first region; the inner wall of the cylinder liner body is provided with a basic mesh pattern, and the average peak-valley height range of the basic mesh pattern is 1~4.5μm, the average peak spacing range is 20~52μm, and the axial included angle of the basic mesh pattern is greater than 135°.

2. The cylinder liner according to claim 1, characterized in that, The first preset area ratio ranges from 1% to 30%, and the second preset area ratio ranges from 10% to 50%.

3. The cylinder liner according to claim 1, characterized in that, The first preset depth ranges from 3 to 10 μm, and the second preset depth ranges from 1 to 8 μm.

4. The cylinder liner according to claim 1, characterized in that, The maximum oil storage volume of each of the aforementioned indentations is 0.006 mm. 3 .

5. The cylinder liner according to claim 1, characterized in that, The cross-sectional area of ​​each of the aforementioned concave points is no greater than 0.6 mm. 2 .

6. The cylinder liner according to claim 1, characterized in that, The third region is provided with the concave point, and the depth of the concave point in the third region is the first preset depth, and the arrangement area ratio is the first preset area ratio.

7. The cylinder liner according to claim 1, characterized in that, The plurality of the dimples are distributed in multiple rows along the circumferential direction of the inner wall of the cylinder liner body, and in multiple columns along the axial direction of the inner wall of the cylinder liner body. The dimples in each adjacent two rows are staggered along the axial direction, and the dimples in each adjacent two columns are staggered along the circumferential direction.

8. An engine, characterized in that, Including the cylinder liner as described in any one of claims 1-7.

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