金属薄板冷轧工艺润滑基础实验研究

以铝合金板和IF钢板为代表,研究金属薄板冷轧工艺润滑的作用与效果。实验对不同润滑条件下冷轧时的轧制工艺参数进行分析,并对金属薄板轧后表面形貌情况进行观察。结果表明:通过冷轧工艺润滑可以明显提高轧机轧制能力、显著降低轧制过程中的力能消耗(轧制力、轧制力矩),有效地改善轧件表面质量。     

铝冷轧乳化液润滑性能研究

研究铝冷轧乳化液润滑性能,分析水基乳化液体积分数对黏度、钢铝之间的摩擦因数、冷轧铝表面质量、成膜能力的影响。结果表明:乳化液体积分数较低时摩擦因数不稳定,表面黏铝严重;乳化液体积分数越高,黏度越大,膜厚越大;摩擦副相对速度达到某个临界值后,乳化液形成的膜厚随着时间而减小,在低速条件下,冷轧铝润滑与离水展着性有关;冷轧铝板上下表面质量的差异是由于供油方式不同,导致油吸附在摩擦副上的量不同,成膜能力不同,因此上、下表面质量不同。     

冷轧润滑过程中的轧制界面热效应研究

通常对冷轧过程的润滑进行分析时,不考虑热效应。但实际生产和实践中发现,当速度较大或者轧制变形量比较大时界面热效应不可忽略。采用综合考虑冷轧润滑过程中轧件表面热量的产生和传导关系,推导出轧件以及润滑膜的温升计算模型,并通过二辊轧制纯铝板的实验来进行验证和说明。结果表明:冷轧润滑过程中,轧件的温升随着轧制速度和压下率的增大而增大,压下率对轧件温升的影响大于轧制速度的影响;对轧件温升起主要作用的是塑性变形热,在轧制变形区内轧件的温度随着变形的增大而增大,并且在最大变形处附近轧件的温度达到最大;润滑膜的温升主要受到轧件表面温升的影响,润滑膜温度随着轧制压下率的增大而升高,当轧制压下率和轧制速度较小时,润滑膜的温度变化不是很明显。     

冷轧乳化液颗粒度与润滑性能的关系

选用合适的基础油与油性剂、抗氧剂、极压抗磨剂和防锈剂等功能添加剂,利用亲油亲水平衡体系调节乳化油的乳化状态制备不同颗粒度分布的冷轧乳化液; 通过MS-10A杠杆式摩擦试验机考察颗粒度与乳化液极压、抗磨性能的关系; 借助实验用四辊可逆冷轧机组,对比分析不同颗粒度分布的乳化液润滑下轧后的板面质量。实验结果表明,乳化液的颗粒度分布与其稳定性和润滑性能存在一定的对应关系;在一定体积平均粒径范围内,随着颗粒度的增大有利于提高乳化液的抗磨减摩性能,改善冷轧成品板面质量。     

环保型高润滑性带钢轧制油的研制

研制一种环保型高润滑性带钢冷轧乳化油。从理化性能指标测试、摩擦学性能评价、小轧机实验及热重-差热实验4个方面对研制的带钢冷轧乳化油进行系统全面的研究分析,并与国内外同类冷轧乳化油进行对比分析。结果表明:研制的环保型带钢冷轧乳化油具有高润滑性能,且退火清净性优于国内外同类带钢冷轧乳化油。工业试验也证明研制的带钢冷轧乳化油可满足现在带钢高速、大压下量冷轧工况要求,能获得高表面质量的带钢,综合性能好,可替代同类进口带钢冷轧乳化油。     

铜带冷轧乳化液极压润滑性能实验研究

通过四球摩擦实验和轧制实验,研究了硫系和磷系极压剂对铜带冷轧乳化液极压润滑性能的影响.基于表征润滑性能的无卡咬载荷和摩擦因数2种参数,提出了评价乳化液极压润滑性能的新指标--极压润滑系数.基于极压润滑系数,分析了硫系极压剂和磷系极压剂的配伍关系与铜带冷轧乳化液极压润滑性能的关系,筛选出了最佳配方.通过冷轧实验,比较了筛选出的各乳化液配方的润滑效果.试验结果表明:润滑效果优劣排序与极压润滑系数大小排序基本吻合,表明极压润滑系数对轧制乳化液极压润滑的判定简单且实用.     

轧辊粗糙度对不锈钢板带表面和工艺参数的影响

不锈钢板带冷轧过程中,轧辊表面粗糙度对轧制工艺参数设定和表面质量控制有重要的影响.在实验室对SUS430不锈钢进行冷轧润滑试验,利用Quanta 600扫描电子显微镜、Zeiss-LSM 700光学显微镜和粗糙度仪等研究冷轧过程中轧辊表面粗糙度对带钢表面粗糙度、表面微观缺陷率、表面油膜厚度和轧制力的影响.结果表明,粗糙度为0.7 μm轧辊在低质量分数乳化液下对带钢表面改善较为明显,高质量分数乳化液下带钢粗糙度随轧辊粗糙度的增加而增加;降低轧辊粗糙度有利于减小表面缺陷率;随着轧辊粗糙度的增加,低质量分数乳化液下带钢表面油膜厚度呈现先增加后减小的趋势,高质量分数乳化液下采用粗糙度0.7μm轧辊,油膜厚度最大;随着轧辊粗糙度的增加,高质量分数乳化液下轧制力逐渐增加,低质量分数乳化液下使用粗糙度0.8 μm轧辊,轧制力较小.     

磷系极压剂在铜板带冷轧乳化液中的应用效果研究

采用四球摩擦试验机分别考察亚磷酸二正丁酯(T304)、磷酸三甲酚酯(T306)和硫代磷酸三苯酯(T309)3种磷系极压剂在基础油中的摩擦学性能,通过铜板带冷轧制实验研究其在乳化液中的润滑作用效果。结果表明,3种含磷添加剂均使基础油的摩擦学性能得到一定程度地提高,其中T304具有优异的承载能力和抗磨减摩性能,其最佳添加量为0.5%～1.5%(质量分数),T306和T309效果较差,且限于中高或中低载荷下工作;T304较T306和T309具有更优异的润滑性能,在轧制过程中有效改善轧制过程特征参数和提高轧件质量,可作为铜板带轧制液高性能的极压抗磨剂。     

乳化油

防锈乳化油防锈乳化油是由防锈剂、乳化剂和矿物油配制而成。与水能调配成水包油型的乳化液(俗称肥皂水),具有防锈、冷却、清洗和润滑作用。适用于金属的一般切削加工,也可作水包油型的液压油。用皂化溶解油加工的机床,可用防锈乳化油替代。使用方法:切削加工一般推荐使用浓度为2～5％,可根据季节和加工工件的质量要求不同而定,如对防锈、润滑要求高     

药剂-电解组合法处理乳化液含油废水的探讨

一、乳化液的概况乳化液俗名肥皂水,是乳化油加水稀释而成,在机械制造和金属压延等工厂中被广泛地作为冷却、润滑和传递压力之用。工厂生产中使用乳化液的浓度(乳化油含量)按需要一般是2％～15％,但由于机器润滑系统泄漏等原因,润滑油难免渗入乳化液,致使乳化液的实际含油量大为增加。乳化液容易酸败变质。酸败主要是由于油脂,尤其是高级不饱和脂肪酸组成的油脂被大气中的氧、二氧化碳所氧化而造成的。油脂的不饱和程度愈高,愈易发生氧化酸败。所以,当乳化液使用了一段时间后,会渐渐变质发臭而失去其作用。过去,几乎所有工厂     

A thermal analysis of strip-rolling in mixed-film lubrication with O/W emulsions

Increase of both roll and strip surface temperatures can significantly affect a rolling process, roll conditions and strip mechanical properties. A comprehensive thermal analysis in cold rolling, especially in a mixed film regime, is needed to understand how thermal fields develop in roll and strip during rolling. It requires a simultaneous solution of the mixed film model for friction in the roll bite and the thermal model for roll and strip thermal fields. This paper presents a numerical procedure to analyse strip rolling process using lubrication with oil-in-water (O/W) emulsions. The thermal model includes the effect of heat generation due to the strip deformation and frictional shear stress at the asperity contacts. The numerical analysis employs a coupled thermal model and a mixed film lubrication model for calculating the friction and the asperity deformation in the bite. The thermal model considers the initial temperatures of the roll and strip, temperature rise due to the strip plastic deformation and friction. While the O/W mixed-film lubrication model takes into account the effect of surface roughness and oil concentration (%vol) of the emulsion. The thermal effect is analysed in terms of strip surface temperature and roll temperature, which are influenced by rolling parameters such as reduction, rolling speed, oil concentration in the emulsion. The results of the parametric study indicate that the effect of oil concentration on the thermal field is relatively small compared to that of reduction ratio and rolling speed. The reduction ratio increases the maximum interface temperature in the roll bite. In the mixed film regime, rolling speed also increases the maximum interface temperature and alters the temperature field of the strip. The numerical procedure was validated against known experimental data and can readily be extended to hot rolling or used to analyse roll strip temperature subjected to different cooling system.     

Control of surface thermal scratch of strip in tandem cold rolling

The thermal scratch seriously affects the surface quality of the cold rolled stainless steel strip. Some researchers have carried out qualitative and theoretical studies in this field. However, there is currently a lack of research on effective forecast and control of thermal scratch defects in practical production, especially in tandem cold rolling. In order to establish precise mathematical model of oil film thickness in deformation zone, the lubrication in cold rolling process of SUS410L stainless steel strip is studied, and major factors affecting oil film thickness are also analyzed. According to the principle of statistics, mathematical model of critical oil film thickness in deformation zone for thermal scratch is built, with fitting and regression analytical method, and then based on temperature comparison method, the criterion for deciding thermal scratch defects is put forward. Storing and calling data through SQL Server 2010, a software on thermal scratch defects control is developed through Microsoft Visual Studio 2008 by MFC technique for stainless steel in tandem cold rolling, and then it is put into practical production. Statistics indicate that the hit rate of thermal scratch is as high as 92.38%, and the occurrence rate of thermal scratch is decreased by 89.13%. Owing to the application of the software, the rolling speed is increased by approximately 9.3%. The software developed provides an effective solution to the problem of thermal scratch defects in tandem cold rolling, and helps to promote products surface quality of stainless steel strips in practical production.     

二次冷轧过程变形区油膜厚度模型

为了定量预报二次冷轧过程轧制变形区油膜厚度,结合二次冷轧机组乳化液直喷系统的设备与工艺特点,分析了带钢表面析出油膜、工作辊表面附着油膜的形成机理,建立了一套二次冷轧过程轧制变形区带钢上下表面油膜厚度模型,定量分析了乳化液流量密度、乳化液浓度、乳化液析出距离、轧机入口轧制速度、轧制咬入角、带钢入口变形抗力、后张力、轧制油初始动力黏度、轧制油压力黏度系数对轧制变形区带钢上下表面油膜厚度的影响,并将该模型应用到某1220二次冷轧机组的生产实践,编制出了相应的模型计算软件,实现了二次冷轧过程变形区油膜厚度的预报,为二次冷轧过程润滑性能的控制奠定了理论基础。     

铝冷轧乳化液的特性

探讨了铝冷轧乳化液在润滑性、退火清净性和热分离性等方面的特殊性能要求，提出了该乳化液配方研究应遵循的原则。     

Experimental and numerical study of O/W emulsion lubricated strip rolling in mixed film regime

An experimental and numerical study of cold rolling lubricated by O/W emulsion has been carried out. The strip rolling experiment was carried out on a Hille experimental rolling mill with a view to study the performance of emulsion lubrication in terms of practical rolling parameters. Accordingly, rolling parameters such as rolling force and torque were measured. The experimental measurements compare favourably with the computed results from a numerical scheme developed by the authors. The scheme, based on a two-phase lubricant model, is capable of calculating the oil concentration at any point within the inlet zone and work zone, rolling pressure, film thickness, and fractional contact area ratio associated with strip rolling under mixed film lubrication at different rolling speeds. Using this scheme, the intertwined effects of an emulsion’s parameters such as: oil concentration, mean oil droplet size, and rolling speed on strip rolling were investigated. The numerical study encompassed the mixed film regime for speed, S ranges from 10⁻⁴ to 10⁻², supply oil concentration level λ_ds from 1 to 10%, and oil droplet size D _S from 5 to 10. Experimentally, the differences between water, oil and emulsion-lubricated rolling are not discernible except for film thickness. At a low speed of 10 RPM, force and torque of water-lubricated rolling are marginally higher than oil- or emulsion-lubricated ones. However, the difference between emulsion and neat oil is not apparent. The numerical results show the occurrence of a moderate oil concentration increase in the inlet zone followed by a sharp one at the beginning of the work zone. The effect of the concentration process is predominantly seen in the film thickness and the lubricant pressure whilst its effect on the total pressure is less pronounced. The analysis of the results suggests that it is possible to lower the emulsion oil concentration without any adverse effect on the rolling process. This principle can be used to control the outlet lubricant film thickness and hence the surface quality of the rolled strip.     

基于正交试验的含氮硼酸酯铝材轧制润滑油摩擦学性能研究

合成一种新型含氮硼酸酯铝材轧制润滑油添加剂,利用四球试验机考察添加含氮硼酸酯的铝材轧制润滑油的油膜强度、摩擦因数,通过显微镜观察磨斑形貌并测量磨斑直径。利用正交试验法评估极压剂含量、基础油种类、四球试验机载荷和转速对含氮硼酸酯润滑油摩擦学性能的影响,并通过多目标优化设计,对4种参数对铝材轧制润滑油摩擦学性能的强化效果进行综合研究。结果表明:各工艺参数对油样的摩擦学性能影响显著性由大到小依次为极压剂添加量、基础油种类、转速和载荷;经过多目标优化设计,得到的含氮硼酸酯铝材轧制润滑油强化工艺参数的最佳组合:极压剂质量分数为1.0%,基础油种类为D100,载荷为294 N,转速为1 200 r/min;通过极差、方差等分析,发现极压剂添加量和基础油种类对油样的摩擦学性能有显著影响。     

内螺纹铜管拉拔工艺润滑研究

鉴于工艺润滑在拉拔内螺纹铜管中的重要作用本文研究了全润滑和浮液润滑的作用，并且进行了分析，对比。另外，对全油润滑剂的粘度与油膜强度；乳液的极压特征与使用浓度与其润滑效果之间的关系也进行了实验研究。     

乳化液性能指标对冷轧效果的影响

介绍乳化液在冷带钢轧制中的工作机理,分析乳化液中的添加剂在冷轧过程中所起到的作用,探讨乳化液主要理化指标与冷轧带钢产品质量间的关系,指出通过调整乳化液理化指标来保证冷轧带钢产品质量的具体方法。     

Elastohydrodynamic Film Thickness and Tractions for Oil-in-Water Emulsions

Emulsions, consisting of a small volume of oil dispersed in water in the form of small particles, are popular lubricants for metal rolling and some machine design applications. A number of mechanisms have been suggested for the lubricating behavior of emulsions, among which plate-out, starvation, and dynamic concentration are of particular interest here. At low speeds, the emulsion provides essentially the same lubricating ability as neat oil for a point contact, consistent with plate-out. At some critical speed, the emulsion behavior departs from the neat oil, associated with starvation of the inlet zone. At a second critical speed, dynamic concentration becomes the important mechanism. This article measures the film thickness and traction coefficients of oil-in-water emulsions in the different regimes of behavior and compares the results to existing theoretical understanding. The effect of droplet size is isolated as a causative element in fluid film formation.     

Evaluation of Occurrence of Surface Brightness Irregularity in Cold Rolling of Stainless Steel with Emulsion

The manufacturing of stainless steel with higher brightness is improved using emulsion oil. However, in cold rolling of stainless steel with emulsion oil, it is well known that the surface brightness irregularity on the sheet surface after rolling occurs when the rolling speed is higher. It is estimated from the experimental results that the cause of the surface brightness irregularity is due to the degree of starvation in the emulsion rolling. The rolling experiments of the stainless steel with oil-in-water emulsion were carried out at various rolling speeds. The inlet oil film thickness was estimated using the evaluating system. In cold sheet rolling of stainless steel with emulsion oil, the surface brightness irregularity occurred at a rolling speed of 0.6 m/s with emulsion concentrations of 3, 5, and 10%. The experimental results showed that the surface brightness irregularity at cold coil rolling with emulsion of stainless steel occurred under a degree of starvation value of 0.16.