Showing papers on "Honing published in 2019"

Honed Surface Multiscale Prediction Based on Multi-Stage Honing Process of Engine Cylinder Bore

Abstract: Sequential honing process is usually implemented in engine cylinder bore processing to obtain the cross-hatched surface texture with excellent function to balance lubricant storage capacities and supporting performance. Many researches have devoted to correlating honed surface quality of cylinder bore with honing process parameters by means of experiments or simulations. Quite a few efforts have addressed the effect of sequential multiple steps on the surface texture in the honing of engine cylinder bore. However, these researches cannot provide an explicit and analytical methodology to predict honed surface texture efficiently and accurately. This paper presents an analytical and explicit methodology to incorporate a proposed microscale abrasive model into the analytical simulation process of sequential honing. The proposed abrasive model synthetically considers the shape, size, posture, and position of abrasives randomly distributed in honing stone, which is incorporated into honing head motions in terms of rotation, oscillation and feeding. The kinematics of honing head is calculated by space-time discretization to capture the interaction between honing stones and cylinder bore surface. The above procedure acts as each single step for the sequential honing processes. This study investigates the sequential honing of two stages including semi-finish honing and plateau honing at different feeding speeds by applying the abrasive model with different abrasive sizes. The formation of cross-hatched surface texture was successfully achieved sequentially by semi-finish honing and plateaus honing. Then the Abbott-Firestone Curve of the honed surface can be obtained to analyze the influences of abrasive size and honing time of two stages on the surface roughness. Correctness of surface roughness predicted by the model is verified by comparing with a group of experiment measurements in terms of Abbott-Firestone Curve. Most errors of all the predicted Rk roughness family roughness parameters in the two honing stages are less than 15%. Based on the model, simulations are done to analyze the influences of abrasive size and honing duration time of two stages on the surface roughness. The result shows that the larger abrasive used in finish honing leads to the decrease of the material portions Mr1, Mr2 and the increase of the reduced valley depth Rvk. The longer plateau honing duration time is preferred to produce the larger Mr1, Mr2 and the smaller Rvk.

The Effect of Honing Angle and Roughness Height on the Tribological Performance of CuNiCr Iron Liner

Abstract: This work investigated the effect of honing morphologies of CuNiCr iron liner on its tribological properties sliding against the Cr-Al2O3 coated piston ring. The worn surface morphology and elements distribution as well as the wear behaviors of CuNiCr iron liner were analyzed to explore the influencing of the honing angle and roughness height on the friction and wear resistance. The results show that the optimized honing angle and roughness can improve the tribological performance of the iron liner, and different tribological characteristics are closely related to different roughness parameters. The wear process of the CuNiCr iron liner against Cr-Al2O3 coated piston rings in sequence was platform flattening, plastic flow, growth of the flakes on the platform edge and flakes debonding. For the smooth surface, the plastic deformed flakes were much fewer due to the low height of the platforms, thus the grooves were not fully filled and there was a slight effect of the debonded debris on the friction pair.

Numerical and Experimental Analysis of the Honing Texture on the Lubrication Performance of Piston Ring–Cylinder Liner Tribosystem

Abstract: A lubrication model of the piston ring–cylinder liner tribosystem taking account of the honing texture was established in this study. The impact of honing texture parameter, which was characterized...

Anti-Wear Property of Aluminum⁻Silicon Alloy Treated by Chemical Etching, Mechanical Honing and Laser Finishing.

Abstract: To enhance the anti-wear property of aluminum-silicon (Al-Si) alloy, three processing technologies-chemical etching, mechanical honing and laser finishing-were compared in terms of their effects on anti-wear performance. The treated Al-Si alloy cylinder liner samples were worn against a piston ring by a reciprocating sliding tribotester; the anti-wear performance was represented by the friction coefficient and wear loss; and the wear mechanism was determined by establishing stress contact models. The results showed that the best time for both the chemical etching and mechanical honing treatments was 2 min, and the optimal laser power was 1000 W for the laser finishing treatment. The three processing technologies could all remove the aluminum layer and make the silicon protrude on the surface to avoid the plastic flow of aluminum during the friction process. The laser finishing could not only protrude the silicon particle but also make its edge rounded and smooth, which decreased the stress concentration. Therefore, the Al-Si alloy cylinder liner treated with laser finishing had the best anti-wear performance.

Surface structuring of polycrystalline diamond (PCD) using ultrashort pulse laser and the study of force conditions

Abstract: In the metal working industry, cutting tools for high precision application are usually made from non-conventional super hard materials, for example, diamond (D) and cubic boron nitride (CBN). These materials are composites of geometrically undefined grains embedded in metallic binder. For some special applications, these tools are constructed from one or several cutting edges and guide rails. Typical examples are honing and guided reaming tools for the fine machining of bores. These tools improve the form, dimension and surface quality, as well as the geometrical tolerances of the machined workpieces. The guide rails of the tool play an important role as they usually support the tool shaft in the rotating movement, for example the guiding stones of the honing tool. In the case of dynamic contact, higher demands on material properties such as hardness and wear resistance are necessary. In this study, a polycrystalline diamond (PCD) grade is employed as a new material for guide rails. Contacting surfaces of the PCD guide rails are textured with three defined patterns by a femtosecond laser setup. It is aimed to improve the force conditions by means of changing the contacting conditions. Within this regard, the tribological properties of the three patterns on PCD rails are characterized using a nanotribometer and compared to the conventional guide rails made of cemented tungsten carbides. A force simulation based on the honing processes is built up and conducted to predict the force conditions of each different pattern. At the same time, morphological modification, assessment of surface and microstructural integrity of the structured PCD guide rails are also studied in this work.

Fabrication and tribological performance of a laser-textured hardmetal guiding stone for honing processes

Abstract: Honing is often implemented as surface finish process by improving geometrical and form precision of workpieces. Guiding stones, usually made of hard materials with requirement of excellent tribological properties, play a key role as a supporting part in the honing tool. In this paper, cemented carbides are intended for guiding application as substitute of diamond or CBN composites. Innovative surface textures, namely crossing-line patterns and dimple arrays, are fabricated by means of short pulse laser on a cemented tungsten carbide (hardmetal) grade. Implementation of these processing conditions yields satisfactory geometrical accuracy. The cemented carbide stones patterned by laser together with a traditional diamond guiding stone were tested on a lubricated pin-on-disc tribometer. Both cross-line patterns or dimple arrays are found to improve frictional conditions compared to the traditional guiding stone, but the former are more favorable to build up a stable sliding scenario with minimized friction than the latter. Pattern density has a more significant impact on friction, diminishing in the case of dimple arrays.

Effect of grain size and density of abrasive on surface roughness, material removal rate and acoustic emission signal in rough honing processes

Abstract: Honing processes provide a special cross-hatch pattern to the internal surface of cylinders that favors oil flow. However, along honing operation the abrasive grains wear out and lose their ability to cut material. The honing chips mixed with oil fill the pores of the abrasives and they start cutting in an incorrect way, leading to clogging. In the present paper, honing experiments were carried out according to a 32 factorial design, with different grain size and density of abrasive grains. Roughness, material removal rate, and tool wear were determined. Acoustic emissions were also measured and the chirplet concept was applied in order to detect differences between correct and incorrect cutting operations. As a general trend roughness and material removal rate increase with grain size and with density of abrasive. However, when clogging occurs roughness and material removal rate decrease, because the abrasive grains tend to deform the material instead of cutting it. When the honing process is working appropriately, the chirplet diagram of the harmonic part of the signal shows constant marks. On the contrary, when it does not work properly, marks disappear with time and their frequencies decrease. The results of the present paper will allow monitoring the honing process in order to change the abrasives when they are not working properly.

A comprehensive study of the effects of honing patterns on twin-land oil control rings friction using both a numerical model and a floating liner engine:

Abstract: Engine bores are finished with a multi-stage honing process and the finished surface roughness contributes significantly to the piston ring hydrodynamic pressure generation, especially for twin-land oil control rings whose land profile is parallel to the liner surface. In this paper, five different honing patterns on a cast iron liner and one on a spray-coated aluminum liner are studied with a floating liner engine and numerical models. The liner temperature and engine speed were varied such that all the lubrication regimes, namely boundary, mixed, and fully hydrodynamic, are present. It is found that the models based on deterministic approach with a patch of carefully measured liner roughness can match the trend of the Stribeck curves for different liner finishes observed in the experiment. Furthermore, the results show that the roughness height and structure of the honing affect the twin-land oil control rings lubrication differently. With the same honing structure, although rougher liner experiences mi...

Effect of grain size and number of strokes on Rk parameters and emptiness coefficient in honing process

Abstract: This paper deals with evaluation of the effect of grain size of abrasive particles and number of tool strokes on the roughness values (Rk, Rpk, Rvk, Mr1, Mr2, and Rp/Rt ratio) in flexible honing. The grain size factor was investigated on two levels (400 and 800 mesh) and the number of tool strokes on three levels (1, 3, and 5) based on a full factorial design 2 × 3. Flexible honing was performed after conventional honing, on 30 crankcase cylinders of hermetic compressors made in gray cast iron. The analysis of variance technique showed that the effect of abrasive grain size on the roughness was more significant than that produced by the number of tool strokes. The abrasive grain size caused statistically significant effects on Rpk, Rk, Mr2, and Rp/Rt, whereas the number of tool strokes affected Rpk only. The interaction between these factors affected Rk. The flexible honing process using 800 mesh tool grain size and five tool strokes allowed for the obtainment of surfaces similar to those that resulted from the plateau honing operation. This result can increase the field of application of this process. Flexible honing was not able to remove the waviness present on the crankcase cylinder surfaces, whose amplitude was similar to those presented by the roughness.

Determination of Shape and Distribution of Abrasive Grains to Reduce Carbon Emissions of Honing Process

Abstract: Due to the increasing concern on environmental sustainability, many efforts have been made to improve the energy efficiency and reduce carbon emissions of manufacturing processes, including abrasive machining processes. Oilstones, as the abrasive tool of honing machines, are the key parts to remove material. However, the theoretical models and methods that can be used to support the selection of oilstone parameters for reduced carbon emissions are lacking. To fill this gap, this paper proposes a method to optimize shape and distribution of abrasive grains for minimized carbon emissions while maintaining surface quality. First, the carbon emissions boundary is defined, and a carbon emissions calculation model is established from a macroperspective. As each grain contributes to the total carbon emissions, the behavior of grains during honing is then described and analyzed to obtain the carbon emissions model from a microperspective. Surface area of oilstones and the required total volume of material removal are kept constant to meet the physical size limit of oilstones and machining requirement of workpiece. Third, a shape and distribution optimization model is developed to minimize carbon emissions. A modified particle swarm optimization (PSO) algorithm is adopted to solve this problem. Finally, the proposed method is applied to a case study to validate its effectiveness. Results show that carbon emissions can be reduced by up to 30% using the proposed model. The proposed method provides a new green manufacturing strategy for the honing process and a possibility to customize abrasive tools to meet the environmental challenges.

Improved design of magnetorheological honing tool based on finite element analysis and experimental examination of its performance

Abstract: The magnetorheological honing (MRH) tool is an advanced finishing tool which is designed and developed to superfinish internal cylindrical surfaces. It uses magnetorheological polishing fluid consisting of carbonyl iron particles and cutting-edge silicon carbide abrasives in viscous fluid medium. The MRH tool with retained polishing fluid is rotated and reciprocated inside a cylindrical workpiece within the gap between the outer surface of the MRH tool and the inner surface of the cylindrical workpiece called the working gap. Due to the relative motion between abrasives (gripped by carbonyl iron particles chains) and the workpiece’s inner surface, finishing action takes place over the inner surface of the cylindrical workpiece. In this paper, two different designs of the MRH tool are designed with the same parameters based on finite element (FE) analysis using Ansoft Maxwell. The FE analysis results in more magnitude and uniformity of magnetic flux density in the working gap for the improved design of the MRH tool. Due to this effect, the abrasives are more strongly held with uniform strength which results in comparatively significant uniform finishing of the internal surface of the cylindrical workpiece. After confirmation of higher and uniform magnetic flux density on the improved MRH tool surface from FE analysis, two designs of the MRH tool are then fabricated with the same dimensions as taken in magnetic simulation. Experimentations have been performed with the fabricated finishing tools over the inner surface of cylindrical ferromagnetic workpiece of mild steel. The MRH tool with improved design results in uniform and more reduction in value of surface roughness with the same finishing time and process parameters as compared to the first proposed design. This confirms the enhancement in the finishing capability and better usefulness of the improved design of the MRH tool.

Modeling and adaptive compensation of tooth surface contour error for internal gearing power honing

Abstract: The machining of high precision gears requires a strict and accurate co-movement relationship controlled by the electronic gearbox between the moving axes of the gear machine tools. This article pr...

Experimental investigations on surface finish and microgeometry of helical gear in pulsed-electrochemical honing process:

Abstract: Gear is one of the most vital mechanical elements for transmission of power and motion. It has been considered as one of the highest consumable mechanical parts. Surface attributes of the gears are...

Involute profile globoidal gear honing

Abstract: In the paper technological potentialities of globoidal gear honing are considered. With this purpose there are used complex measurements for involute gearings. A problem on a design definition of globoidal gear honing errors depending on machining conditions and parameters of a hone installation is solved. The results are presented as Talyrond traces of actual parameter deviations of the involute from theoretical ones (design parameters).

Detecting device for honing hole

Abstract: The invention belongs to the field of mechanical manufacturing, and particularly relates to a detecting device for a honing hole. The detecting device comprises an aperture self-adaption part, a driving part, a detecting part and an operation display part. The detecting part comprises a straightness detecting assembly, a diameter detecting assembly, a groove detecting assembly, an inner hole observing assembly and a roughness detecting assembly. The detecting part can also be any one or two or three or four of the five assemblies. With the assistance of the deformation of a spring, a spring sleeve can self-adapt to the aperture change. A pull rod is connected with a front disc, the front disc and a rear disc are connected, and a front cover is driven by a universal joint. An inner laser illuminates an outer photosensor. A laser range finder is fixed to a rear cone or a front cone, and lasers of the laser range finder illuminate the hole wall and the groove bottom. The hole wall is observed by an endoscope and a rearview mirror. The device can measure the roughness. The device has the advantages that the laser adjustment is convenient, the acting direction of driving force is the axis direction of the honing hole, the detection precision is high, and the purpose of measuring an inner hole and an inner groove is achieved.

Influences of control error and setting error on machining accuracy of internal gearing power honing

Abstract: As a high efficiency and high precision machining process, internal gearing power honing is often used in gear finishing after heat treatment In order to improve the machining accuracy of internal gearing power honing, this paper analyzes the influence law of motion control error and machine setting error on tooth surface contour error First, the tooth surface of the honing wheel and the workpiece gear is established by using homogeneous coordinate transformation and meshing principle Second, the tooth surface of the workpiece with the control error and the setting error is constructed The contour error and the sensitivity matrix of the tooth surface are also put forward Finally, two numerical examples and an experiment are used to study the influences of control error and setting error on the machining accuracy of workpiece gear tooth surface The research results can provide reference and precondition for the error compensation and improvement of machining precision of internal gearing power honing

Resource-efficient piston ring/cylinder liner pairing

Abstract: Purpose The purpose of this paper is to investigate the influence of different finish processes on the surface integrity and tribological behaviour of cylinder running surfaces for internal combustion engines. Design/methodology/approach The cutting force during finishing and the resulting surface topography was measured for a variety of cylinder running surfaces made of EN-GJL-250, EN-GJV-400 and thermal sprayed aluminium alloy. A separate conditioning tool was developed and tested. Different analysis methods (SEM, EDX, SIMS and FIB) for the characterisation of the boundary conditions were used. By an oscillating friction wear test and a single cylinder floating liner engine, the running-in and frictional behaviour was rated. Findings It was shown that honing with low cutting forces and silicon carbide cutting material decreases the friction in operation. The characteristics of the boundary layers after running-in depend on the finish machining process. A preconditioning with a separate tool can adjust the boundary layer and running-in behaviour. Based on the experimental results, a multi-body and computational fluid dynamics simulation was developed for the floating liner engine. Originality/value The results demonstrate the potential of finishing with low process forces to reduce friction and the need for a complete consideration of the tribological system piston ring/cylinder liner surface.

Honing device for casting hole machining

Abstract: The utility model provides a honing device for casting hole machining. Wherein the two supporting rods are symmetrically and vertically connected to the upper end of the bottom plate, the same top plate is vertically connected to the upper ends of the supporting rods, and the machining base is fixedly connected to the middle of the upper end of the bottom plate. A workpiece containing groove is formed in the upper end of the machining base, a honing workpiece is clamped in the workpiece containing groove, a casting hole is formed in the honing workpiece, and a honing device is arranged in the casting hole. The high honing device overcomes the defects in the prior art, is reasonable in design and compact in structure, pushes the four honing oilstone strips to expand outwards intermittently by arranging the abutting device in the high honing device, effectively pushes honing oilstones to make full contact with casting holes, and greatly improves honing efficiency.

Mounting structure of taper shank honing tool

Abstract: The utility model relates to the technical field of honing tools. The utility model relates to a honing tool, in particular to a taper shank honing tool mounting structure. The honing rod comprises ahoning rod body and a taper mandrel arranged in an inner hole of the honing rod body in a sliding and penetrating mode. At least one radial through hole communicated with an inner hole of the honing rod is formed in the outer circle face of the front end of the honing rod. a bottom plate is arranged in the radial through hole in a sliding manner; a honing strip is fixed on the bottom plate; wherein the top surface of the honing strip is an arc-shaped working surface, the rear end of the honing rod is provided with a mounting part which is conveniently assembled with a main shaft of an externalhoning machine, the appearance of the mounting part is in a taper shank shape, and the outer conical surface of the mounting part is attached to the inner conical surface of the main shaft of the external honing machine and is locked by a locking mechanism on the main shaft of the external honing machine; a groove matched with a boss in a spindle of an external honing machine is formed in the endface of the mounting part so as to prevent the honing rod from rotating. By adopting the taper shank connecting mode, the contact area between the honing tool and an external honing machine main shaft can be increased, and the positioning precision is greatly improved.

Abrasion layer wear at globoidal gear honing

Abstract: The paper reports the calculation-experimental method for the definition of abrasion layer wear parameters and presents the results of these parameters changes depending on machining conditions at globoidal gear honing. As a parameter for the definition working surface wear in a globoidal gear hone with organic rubber-based binding there is chosen a parameter widely used for the assessment of diamond tool wear – specific consumption of abrasion. The use of this parameter allows defining dimension wear of tool abrasion layer in a computation way, including operation surfaces of the globoidal hone.

Thin-walled elongated pipe member whole precision processing method

Abstract: The invention provides a thin-walled elongated pipe member whole precision processing method. The thin-walled elongated pipe member whole precision processing method comprises the following steps of S1, blanking; S2, hot working; S3, rough turning of the end face and the outer circle; S4, drilling and boring of an inner hole; S5, honing of the inner hole; S6, semi-finish turning and finish turningof the outer circle; S7, fine grinding of the outer circle; S8, micro-extrusion correction; S9, finish turning of the end face; and S10, inspection and packaging. By means of the method, the whole precision machining of thin-walled elongated pipe members which are made of austenitic stainless steel materials, have the maximum length being 575 mm, have the minimum pipe diameter being 24 mm, have the maximum draw ratio being 24 and have the thinnest wall thickness being 0.3 mm can be achieved, and the inner hole and outer circle precision reaches the IT5 stage, the coaxiality reaches 0.025 mm,the straightness reaches 0.025mm, the surface roughness reaches Ra0.8, and the method is a high-efficiency, precise and low-cost thin-walled elongated pipe member processing method.

The invention discloses an automatic feeding and discharging tool clamp for cylinder sleeve honing

Abstract: The utility model discloses an automatic feeding and discharging tool clamp for cylinder sleeve honing. The honing device comprises a plurality of feeding discs and a honing workbench, the feeding discs and the honing workbench are arranged at intervals, the lower portions of the feeding discs and the lower portion of the honing workbench are connected in series through linear rails, a sliding block is arranged on the linear rail between every two adjacent feeding discs and honing workbench, and a guide rod air cylinder is fixed to each sliding block; Gaps opposite to the linear rails in position are formed in the portions, located above the linear rails, of the feeding disc and the honing workbench; A proximity switch acting on the sliding block is arranged on the portion, corresponding to the linear rail, below the honing workbench. The feeding disc and the honing workbench are each provided with a cylinder sleeve containing circular groove, and a tray is arranged in the center of each containing circular groove. The cylinder sleeve feeding and discharging device has the advantages that continuous feeding and discharging of cylinder sleeves can be achieved, coarse grinding and accurate grinding can be automatically and continuously conducted, the number of workers and the labor intensity are effectively reduced, meanwhile, time is saved, and the labor efficiency is improved.

Expansion core overlapping type automatic detection double-expansion honing head

Abstract: The utility model discloses an expansion core overlapping type automatic detection double-expansion honing head which comprises a grinding head body, a rough honing feeding mechanism, a fine honing feeding mechanism, a rough honing reset mechanism and a fine honing reset mechanism The grinding head body is provided with a center hole The rough honing feeding mechanism comprises an outer push rod, an outer expansion core rod, an outer expansion core and a rough honing abrasive strip seat; the fine honing feeding mechanism comprises an inner push rod, an inner expansion core rod, an inner expansion core and a fine honing abrasive strip base The honing head provided by the utility model adopts a double-feeding mechanism; according to the honing device, the two procedures of rough honing and fine honing can be carried out at the same time and can also be independently completed, the respective cutting performance of rough honing and fine honing can be brought into full play, real-time monitoring of the bore diameter of the cylinder bore is achieved in the honing machining process, the machining efficiency is improved, and the surface structure requirement of the cylinder bore can beeffectively met