Influence of lubricant and coolant fluid on the cutting force in small-increment planing

The critical cut thickness is determined in planing various materials. With greater thickness, the use of lubricant and coolant fluid reduces the cutting forces. Therefore, with limited rigidity of the technological system, the use of lubricant and coolant fluid is only expedient at above-critical cut thickness.     

Dry cutting of hard-to-machine materials,with compensation of the physical functions of the lubricant and coolant fluid

Russian Engineering Research -     

Influence of lubricant and coolant fluid on diamond consumption in grinding

Water-based lubricant and coolant fluids increase diamond-wheel consumption in below-critical cutting, on account of the increased wear rate of the diamond grains under cyclic thermal stress. In above-critical cutting, such fluids reduce diamond consumption, as a result of slower wear of the diamond grains.     

Influence of the external conditions and the lubricant and coolant fluid on tool-blank contact

Russian Engineering Research -     

Study on lubricating characteristic and tool wear with water vapor as coolant and lubricant in green cutting

In recent years, green cutting is becoming increasingly more popular due to concern regarding the safety of the environment and operator health. The efficiency of metal cutting operation depends upon the frictional/thermal conditions at the tool–chip interface. Use of water vapor, gases (carbon dioxide, oxygen), WV&C (mixture of water vapor and carbon dioxide gas) and WV&O (mixture of water vapor and oxygen gas) as coolants and lubricants to improve the frictional/thermal conditions in turning operations are studied here. In this study, the effects of water vapor, gases, mixture of water vapor and gas, oil water emulsion applications and dry cutting on main cutting force, cutting temperature, chip deformation coefficient (count backwards of cutting ratio), rake face wear, and tool flank wear have been examined in turning ANSI 1045 steel material with cement carbide tool P10. Experimental results show that applications of water vapor, gases and mixture of water vapor and gas reduce main cutting force comparing to dry cutting and wet cutting. Water vapor reduces lower cutting temperature and chip deformation coefficient than others lubricating conditions. The tool life is extended much longer in direct on applications of water vapor and mixture of vapor and gas than dry cutting. The diffusion and adhesion is alleviated with application of water vapor because of chemical reaction between water vapor and metal surface and forming boundary lubrication layer of multi-dimension metal oxidation.     

Simulation of the mixing of components in lubricant and coolant fluids

Simulation of the mixing of lubricant and coolant fluids using equipment with a rotary vibrational drive is considered. Such simulation provides information regarding numerous physical effects.     

简述润滑、冷却用油劣化后的再生处理

论述润滑、冷却用油劣化后再生处理的经济实用性及劣化油再生处理中所面临的技术、设备要求,介绍一项较经济实用的劣化油再生处理技术,可以对企业的节能降耗和环境保护工作起到积极作用。     

Impact of lubricant formulation on the friction properties of carbon fiber clutch plates

Since their introduction over ten years ago, carbon fiber based friction materials have been employed by transmission builders in a wide variety of applications, including torque converter clutches, synchronizers, limited slip devices and shifting clutches. This new generation of materials gives improved durability relative to cellulose; carbon fiber materials offer inherently greater wear resistance and improved resistance to thermal degradation. However, carbon fiber based materials also bring inherently different friction characteristics than their cellulose based counterparts. As a result, a different approach to lubricant formulation is required to provide optimized friction control in applications where they are used. It is well known that in order to achieve and maintain the required friction in a clutch, the correct combination of surface properties and additive chemistry is required. In this paper the impact of different additive chemistries on the friction of carbon fiber clutch plates has been investigated. It will be shown that with the appropriate choice of additive system, carbon fiber based friction plates can offer a number of performance improvements over more conventional materials. Copyright © 2006 John Wiley & Sons, Ltd.     

Wet clutch transmission fluid for AWD differentials: influence of lubricant additives on friction characteristics

In recent years, several electronically controllable automotive transmission systems using wet clutches as intelligent differentials have emerged on the market. These applications place great demands on the anti‐shudder properties of the transmission fluids used. The aims of this study were (i) to investigate the influence of different additives on the friction characteristics of a transmission fluid for all‐wheel drive systems featuring wet multi‐plate clutch with a sintered brass‐based friction material and, based on this knowledge, (ii) to formulate a new transmission fluid with the desired frictional properties. In addition to excellent anti‐shudder properties, the new fluid was required to lubricate hypoid gears under high load. To meet this requirement, it is necessary to add significant amounts of extreme pressure additives to the base oil, which are known to have an unfavourable influence on anti‐shudder properties, necessitating the adoption of novel additive technologies. The additives studied include anti‐wear additives, friction modifiers, corrosion inhibitors, detergents, antioxidants and extreme pressure additives. This paper shows how different additives affect friction in different ways, and that the interactions between the different additives are important to consider. It was concluded that it is feasible to combine good anti‐shudder properties for wet clutches with good lubrication of hypoid gears. Copyright © 2006 John Wiley and Sons, Ltd.     

Analysis of cutting properties with reference to amount of coolant used in an environment-conscious turning process

In the recent years, environmentally conscious design and manufacturing technologies have attracted considerable attention. The coolants, lubricants, solvents, metallic chips and discarded tools from manufacturing operations will harm our environment and the earth’s ecosystem. In the present work, the Tukey method of multiple comparisons is used to select the minimum level of coolant required in a turning process. The amount of coolant is varied in 270 designed experiments and the parameters cutting temperature, surface roughness, and specific cutting energy are carefully evaluated. The effects of coolant mix ratio as well as the amount of coolant on the turning process are studied in the present work. The cutting temperature and surface roughness for different quantity of coolant are investigated by analysis of variance (ANOVA)-test and a multiple comparison method. ANOVA-test results signify that the average tool temperature and surface roughness depend on the amount of coolant. Based on Tukey’s Honestly Significant Difference (HSD) method, one of the multiple comparison methods, the minimum level of coolant is 1.0 L/min with 2% mix ratio in the aspect of controlling tool temperature. F-test concludes that the amount of coolant used does not have any significant effect on specific cutting energy. Finally, Tukey method ascertains that 0.5 L/min with 6% mix ratio is the minimum level of coolant required in turning process without any serious degradation of the surface finish. Considering all aspects of cutting, the minimum coolant required is 1.0 L/min with 6% mix ratio. It is merely half the coolant currently used i.e. 2.0 L/min with 10% mix ratio. Minimal use of coolant not only economically desirable for reducing manufacturing cost but also it imparts fewer hazards to human health. Also, sparing use of coolant will eventually transform the turning process into a more environment-conscious manufacturing process.     

High-strength ceramic composite with nanostructural coating in environmentally benign dry cutting with compensation of lubricant properties

Russian Engineering Research -     

Hydrodynamical modelling of lubricant friction between rough surfaces

The steady Couette flow of a Newtonian fluid between two plates, one of them a plane, the other one provided with riblets aligned perpendicular to the flow direction, is taken as a model for lubricant friction with wall roughness. In cases where the amplitude of the riblets is small compared to the riblet spacing, Reynolds lubrication approximation leads to an explicit solution. In contrast to this, a treatment of the full hydrodynamic equations is required for higher amplitudes. Under creeping flow conditions, an analytical treatment of the Stokes equations based on complex function theory allows for a reduction of the problem to the solving of ordinary differential and integral equations for functions of one variable. After this problem reduction, the resulting equations are solved by Fourier analysis and computer algebra.The resulting streamline patterns of the flow reveal the formation of vortices under certain conditions. Since these vortices act like a kind of fluid roller bearings, their influence on the drag force and material transport of the lubricant is studied.     

High-strength ceramic composite with nanostructural coating in environmentally benign dry cutting with compensation of lubricant properties

Russian Engineering Research -