微量油雾冷却&润滑工艺研究及应用

为了解微量油雾冷却润滑对不锈钢切削性能的影响,在介绍了微量油雾冷却原理及优势的基础上,基于前期实地调研结果,以上汽LFV49180-12350不锈钢涡轮壳进气法兰工序为载体,开展不锈钢的微量润滑铣削性能实验研究。以油品类型、流量大小、喷嘴结构三个因素作为变化因素,探明不锈钢在干切削、传统润滑和微量润滑(外喷)切削条件下的切削性能变化。研究结果表明,流量大小及喷嘴结构是影响不锈钢零件切削性能、尤其是发热量的主要因素。     

基于微量润滑的切削油雾雾化特性测试与分析

微量润滑切削时,切削油雾的粒径分布与浓度等是衡量切削环境空气质量必不可少的特征变量,同时也是揭示微量润滑切削机理的重要参数.本文基于光衍射原理对油雾颗粒的体积分布等进行测量,深入分析了微量润滑条件下切削油雾的雾化特性,揭示了微量润滑系统各参数如润滑油用量、供气压力、喷射靶距及润滑油黏度等对油雾颗粒体积分布的影响规律,为...     

基于微量润滑的两级雾化仿真与试验研究

微量润滑切削过程中,切削油雾浓度和粒径分布是影响切削环境空气质量的重要变量,而润滑油的雾化效果与切削现场的油雾浓度和粒径分布密切相关。首先分析了微量润滑油的雾化机理,据此建立雾化数学模型,同时基于商用微量润滑喷嘴结构建立仿真模型,进而采用Fluent软件对微量润滑油的雾化过程进行数值模拟,研究供气压力对雾化效果的影响,并进行试验验证。     

微量润滑系统参数对切削环境空气质量的影响

微量润滑(Minimum quantity lubrication,MQL)切削是现代机加工领域一项先进的准干式切削技术,但微量润滑切削过程中产生的切削油雾仍会影响切削现场的环境空气质量,危害切削场所人员的健康。基于重量分析法,对微量润滑条件下的切削现场油雾浓度进行了测量与分析,揭示了润滑油用量、供气压力、喷射靶距、射流温度以及润滑油特性等微量润滑系统参数对切削现场油雾浓度PM10与PM2.5的影响规律。研究结果表明,润滑油用量是影响切削现场油雾浓度的最主要因素,随着润滑油用量的增加,切削现场油雾浓度显著增大,应控制在15 mL/h以内;在射流温度较低的条件下,空气中悬浮的水汽会发生凝结与黏附现象,从而造成低温微量润滑条件下的油雾浓度检测结果较室温条件下明显增大,但低温微量润滑条件下切削现场油雾浓度会随着射流温度的降低而相对降低。     

MQL加工的微量冷却润滑系统

针对大量浇注式传统切削冷却润滑存在的主要问题,提出并构建了由供液系统、切削液和雾液回收装置所组成的适用于MQL加工的微量切削液冷却润滑系统,并阐述了微量冷却润滑系统对机床、工具系统和刀具兼容性的要求,为制造微量切削液冷却润滑系统和实施MQL加工工艺提供了理论和工程依据.     

MQL加工的微量冷却润滑系统

针对大量浇注式传统切削冷却润滑存在的主要问题，提出并构建了由供液系统、切削液和雾液回收装置所组成的适用于MQL加工的微量切削液冷却润滑系统，并阐述了微量冷却润滑系统对机床、工具系统和刀具兼容性的要求，为制造微量切削液冷却润滑系统和实施MQL加工工艺提供了理论和工程依据。     

机床产品向绿色清洁生产迈进

<正>清洁化、低能耗的绿色制造已经成为21世纪机械制造业的发展方向,也是机床工具行业一直关注的可持续发展话题。微量润滑技术、油雾回收技术以及水溶性切削液等先进技术和产品的广泛应用,使得机床产品也逐步向着绿色环保、清洁生产迈进。(1)面向机床的微量润滑及油雾回收技术微量润滑技术是金属切削行业中的新技术,其在生产时间和成本的节约方面有明显的效果,在环境保     

微量润滑系统油雾调控及雾粒特性研究

微量润滑油雾调控及雾粒传输方式直接影响油雾状态的变化，进而影响喷射至切削区域的雾粒特性。基于内置式微量润滑雾化技术和油雾内部传输应用特点，研究了不同微量润滑雾化参数和雾粒传输方式条件下油量调控性能和调控规律，并结合传输管路油雾出口雾粒特征，揭示了油雾传输管路内径和传输行程对雾粒特性的影响规律。研究结果表明，雾化室压差在传输油雾量调控上比进气压力作用显著，需要结合压差和进气压力二者影响来考虑雾化器开启数量以对传输油雾量进行调节，在传输过程中传输管路尺寸与行程是影响油雾雾粒特性的重要因素。     

静电微量润滑气雾特性及其切削加工性能研究

静电微量润滑(Electrostatic minimum quantity lubrication,EMQL)技术可显著提高荷电润滑液滴在加工区域的润湿、渗透和沉积性能,改善气雾的润滑冷却能力,降低切削环境油雾浓度。在构建静电微量润滑切削加工系统的基础上,分析了EMQL下荷电电压对润滑油液滴粒径、分布、润湿性和沉积性的影响。研究了EMQL的稳态换热能力,加工环境油雾浓度和切削性能。最后通过刀具磨损分析,揭示了EMQL切削加工时的作用机理。结果表明:荷电后润滑油液滴的粒径减小,分布更加均匀,润湿和沉积性提高。与传统MQL比较,EMQL下的切削温度降低了～14%,环境油雾浓度减小了～8%,刀具磨损下降了～37%,工件表面质量提高了～28%。EMQL加工时,润湿渗透性能改善的小粒径润滑油液滴易在刀具-工件接触面吸附,渗透和铺展,利于切削界面的润滑与换热,车削加工性能更好。     

基于MQL的超声椭圆振动微切削Inconel718的机理研究

研究不同切削条件下的超声椭圆振动(Ultrasonic elliptical vibration,UEV)对Inconel718微切削性能的影响规律,讨论微量润滑(Minimum quantity lubrication,MQL)和UEV切削对加工性能的影响机理.针对微量润滑切削时的不同喷嘴角度,提出一种新的换热模型,利用软件对Inconel718微切削的切削力、切削温度进行了仿真研究,并通过试验对不同喷嘴角度下的切削温度的进行了对比,探讨不同喷嘴角度对UEV切削条件下加工性能的影响.研究结果表明,与常规切削相比,UEV切削可降低切削力、切削温度,超声椭圆振动微量润滑切(UEV+MQL)效果明显,喷嘴角度为0°条件下超声振动微切削Inconel718的切削温度降低效果最为明显.     

Experimental evaluation on the effect of electrostatic minimum quantity lubrication (EMQL) in end milling of stainless steels

The machining of stainless steels is very challenging owing to their high toughness and low thermal conductivity, causing high cutting temperatures and rapid tool wear. Conventionally, metalworking fluids in flood form are used during the process to improve surface quality and tool life; however, their use raises issues including environmental pollution and economic concerns. Therefore, an electrostatic minimal quantity lubrication (EMQL) technology was developed to reduce the consumption of metalworking fluids. EMQL is a near-dry machining technology utilizing the synergetic effects between electrostatic spraying and minimum quantity lubrication (MQL), wherein the lubricant is to apply in a form of fine, uniform and highly penetrable and wettable mist droplets directly to the cutting zone. This study investigates the effect of EMQL in end milling of AISI 304 stainless steel in comparison with dry, wet and MQL machining. The results suggest that EMQL reduces tool wear and cutting force, prolongs tool life considerably and enhances surface finish compared with conventional wet and MQL machining. scanning electron microscopy and Energy-dispersive X-ray spectroscopy analyses show that EMQL considerably reduces adhesive and abrasive wear on the flank face because of the lower friction and heat generation resulting from more efficient entry of the lubricant into the cutting interfaces.     

喷油嘴微孔电火花加工机床机电控制系统设计

喷油嘴喷孔加工质量直接影响发动机的燃料喷射和燃烧性能。喷油嘴喷孔机械钻削加工已难以适应高压力、微细喷孔喷油嘴发展的需要。微细电火花加工喷油嘴喷孔具有无宏观加工力、无毛刺、可加工微细喷孔以及可在热处理后加工等优点。文章结合自主设计研发的喷油嘴微细孔电火花加工机床,设计了机床的机电伺服控制系统,并进行了控制系统性能优化,进行了喷油嘴微细喷孔的电火花加工实验和工业应用,较好地满足了喷油嘴微细喷孔加工的工业需求。     

Investigation and optimization of lubrication parameters in high speed turning of superalloy Inconel 718

Dry machining is sometimes less effective when higher machining efficiency, better surface finish quality, and severe cutting conditions are required. For these situations, semi-dry operations utilizing very small amount of cutting fluids called minimum quantity lubrication is expected to become a powerful tool and played a significant role in a number of practical applications. It has been observed from the literature survey that a systematic research work has to be carried out to determine the optimum quantity of lubricant with appropriate cutting conditions for achieving better machinability characteristics of a material. Hence, an attempt has been made in this paper to enhance the machinability characteristics in high speed turning of superalloy Inconel 718 using quantity of lubricant, delivery pressure at the nozzle, frequency of pulses, direction of application of cutting fluid, cutting speed, and feed rate as the process parameters. Results indicated that the use of optimized minimum quantity lubrication parameters under pulsed jet mode leads to lower cutting force, cutting temperature, and flank wear.     

不同冷却润滑条件下TB6钛合金高速切削表面完整性研究

通过TB6钛合金高速铣削试验,测量观察加工表面粗糙度、表面三维形貌和表层微观组织等表面完整性特征,利用极差法分析切削参数对表面粗糙度影响的显著性,探讨冷却润滑条件对加工表面形貌和表面变质层的影响。研究表明:工艺参数对表面粗糙度影响程度依次为径向切深、切削速度、进给量和轴向切深;相比低温冷风加,微油雾润滑加工时钛合金表面粗糙度低,且表面无明显晶粒变形,表明加工表面塑性变形是影响粗糙度的主要因素。     

An investigation of optimum SiO2 nanolubrication parameters in end milling of aerospace Al6061-T6 alloy

Aluminium AL6061-T6 is a common alloy which is used for many purposes since it has the superior mechanical properties such as hardness and weldability. It is commonly used in aircraft, automotive and packaging food industries. Milling of Al6061-T6 would be a good process especially in producing varieties shape of products to adapt with different applications. The capability of the CNC milling machine to make batch production would be a noteworthy advantage. However, the demand for high quality focuses attention on product quality, especially the roughness of the machined surface, because of its effect on product appearance, function and reliability. Introducing correct lubrication in the machining zone could improve the tribological characteristic of Al6061-T6 leading to higher product quality. In this research work, the optimum SiO₂ nanolubrication parameters in milling of Al6061-T6 are investigated to achieve correct lubrication conditions for the lowest cutting force, cutting temperature and surface roughness. These parameters include nanolubricant concentration, nozzle angle and air carrier pressure. Taguchi optimization method is used with standard orthogonal array L₁₆(4)³. Furthermore, analyses on surface roughness and cutting force are conducted using signal-to-noise (S/N) response analysis and the analysis of variance (Pareto ANOVA) to determine which process parameters are statistically significant. Finally, confirmation tests were carried out to investigate the optimization improvements.     

微量油膜水滴切削加工不锈钢的效果试验研究

主要应用微量油膜水滴切削液,在C620-1普通机床上,通过改变切削速度、进给量以及调整喷嘴的喷射角度,对奥氏体1Cr18Ni9Ti不锈钢材料进行切削加工的效果试验研究。试验结果表明,与干切削、乳化液切削相比,微量油膜水滴切削不仅能够有效地降低切削力和加工表面粗糙度,而且其刀具寿命分别是干切削、乳化液切削的2.28倍和1.6倍。在喷射方向效果研究中,微量油膜水滴在对刀具后刀面和侧面进行喷射的切削加工效果更佳。试验研究表明,微量油膜水滴切削液具有一定的冷却效果和良好的润滑效果。     

Cutting force reduction and surface quality improvement in machining of aerospace duralumin AL-2017-T4 using carbon onion nanolubrication system

In machining of very high precision Duralumin AL-2017-T4 for aerospace applications, the shape varieties of the product lead to many different complicated shapes to be developed. The computer numerical control (CNC) milling machine facilities provides a wide variety of parameter set-up, making the machining process on the Duralumin AL-2017-T4 excellent in manufacturing complicated special products compared with other machining processes. However, the demand for high quality and fully automated production focuses attention on the cutting process, which are partial determinant of the quality of surface and affects the appearance, function, and reliability of the products. The key solution is to increase the effectiveness of existing lubrication systems in the machining process in order to improve product quality as it could reduce the friction component at the tool–chip interface. For further improvement, introducing the nanolubrication system could reduce the cutting force and produce much better surface quality as the rolling action of billions units of nanoparticles at the tool–chip interface could reduce the coefficient of friction significantly. In this study, carbon onion has been used as nanoparticle mixed with ordinary mineral oil at different concentrations to investigate the cutting force reduction and the surface quality improvement of CNC end-milling machined Duralumin AL-2017-T4. From the results, with using of carbon onion nanolubricant, the cutting force and surface roughness values are reduced by 21.99 and 46.32 %, respectively, compared with the case of using ordinary lubrication systems. This can be attributed to the tribological properties of carbon onion, which reduces the coefficient of friction at the tool–chip interface during the machining process.     

Influence of minimum quantity lubrication parameters on tool wear and surface roughness in milling of forged steel

The minimum quantity of lubrication (MQL) technique is becoming increasingly more popular due to the safety of environment.Moreover,MQL technique not only leads to economical benefits by way of saving ...     

Evaluation of machining performance in cryogenic machining of Inconel 718 and comparison with dry and MQL machining

There has been significant work on establishing relationships between machining performance and the cutting parameters for various work materials. Recent trends in machining research show that major efforts are being made to understand the impact of various cooling/lubrication methods on machining performance and surface integrity characteristics, all aimed at improving process and product performance. This study presents the experimental results of cryogenic machining of Inconel 718, a high-temperature aerospace alloy, and comparison of its performance in dry and minimum quantity lubrication machining. Experimental data on force components, progressive tool wear parameters such as flank wear, notch wear, crater wear, cutting temperature, chip morphology, and surface roughness/topography of machined samples are presented. New findings show that cryogenic machining is a promising research direction for machining of high-temperature aerospace alloy, Inconel 718, as it offers improved machining performance in terms of reduced tool wear, temperature, and improved surface quality. It was also found that the number of nozzles in cryogenic machining plays a vital role in controlling cutting forces and power consumption in cryogenic machining of Inconel 718.     

Enhancement and verification of a machined surface quality for glass milling operation using CBN grinding tool—Taguchi approach

Nowadays, the demand for high product quality focuses extensive attention to the quality of machined surface. The (CNC) milling machine facilities provides a wide variety of parameters set-up, making the machining process on the glass excellent in manufacturing complicated special products compared with other machining processes. However, the application of grinding process on the CNC milling machine could be an ideal solution to improve the product quality, but adopting the right machining parameters is required. Taguchi optimization method was used to estimate optimum machining parameters with standard orthogonal array L₁₆ (4⁴) to replace the conventional trial and error method as it is time-consuming. Moreover, analyses on surface roughness and cutting force are applied which are partial determinant of the quality of surface and cutting process. These analyses are conducted using signal to noise (S/N) response analysis and the analysis of variance (Pareto ANOVA) to determine which process parameters are statistically significant. In glass milling operation, several machining parameters are considered to be significant in affecting surface roughness and cutting forces. These parameters include the lubrication pressure, spindle speed, feed rate, and depth of cut as control factors. While, the lubrication direction is considered as a noise factor in the experiments. Finally, verification tests are carried out to investigate the improvement of the optimization. The results showed an improvement of 49.02% and 26.28% in the surface roughness and cutting force performance, respectively.