精密螺纹攻丝器研制成功

第二重型机械集团公司下属子公司—万源精工有限责任公司近期成功研制新型螺纹攻丝器。该螺纹攻丝器在镗床、铣床、钻床等机床上加工螺纹时 ,机床主轴只做旋转而不做轴向移动 ,主轴在为丝锥提供扭矩的同时 ,通过攻丝器上的特殊机构 ,将轴向分力传给攻丝夹头 ,从而使攻丝的轴向运动与被加工螺纹的螺距自动匹配 ,解决了现有加工螺纹精度较低的问题。经过长期反复试验 ,该攻丝器加工出的螺纹不乱扣、精度高 ,具有自动保护功能精密螺纹攻丝器研制成功     

防滑钻夹头

防滑钻夹头是在原扳手式钻夹头的基础上,经过改进后的一项发明,是更新换代产品。 现在的钻夹头使用一段时间后,扳手和外套容易发生打滑现象,大都用铁棒等锤击钻夹头的外套,以便夹紧钻头,所以钻夹头     

丝锥用Nb微合金化TGM2A-S高速钢的开发

TGM2A-S钢(/%:0.85C、0.27Si、0.24Mn、0.026P、0.007S、3.98Cr、4.76Mo、6.09W、1.83V、0.12Nb、0.03RE)是在高速钢TGM2A的基础上添加微量铌和稀土开发的新型丝锥用高速钢。TGM2A-S钢的生产工艺流程为25 t EAF-30 t LF-VD(微合金化)-铸锭(700 kg)二火锻造(85 mm方)-连轧(Φ8 mm)-冷拉(Φ6.6 mm)-加工丝锥(M6)。结果表明,原工艺:3 t中频感应炉-ESR (280 kg锭)-二火锻造(85 mm方)-连轧(Φ8 mm)-冷拉(Φ6.6 mm)-加工丝锥(M6)生产的TGM2A钢中的O和N含量分别为35.4×10^-6和123.6×10^-6,而改进工艺生产的TGM2A-S钢的O和N含量分别为15.7×10^-6和87.7×10^-6。TGM2A-S钢的丝锥切削寿命较电渣工艺生产的TGM2A钢提高20%; TGM2A-S钢的淬火晶粒为10.5级,电渣工艺生产的TGM2A钢的晶粒度为10级。     

一种轧辊在线修磨装置的轴向摆动机构

一种轧辊在线修磨装置的轴向摆动机构，包括传动电机、齿轮、齿条、外套、导向梁、移动导辊、导辊轴；传动电机的输出轴与齿轮相连，齿轮与齿条啮合；导向梁为工字形，上部开有凹槽，齿条及与其啮合的齿轮安装于凹槽中，导向梁左右两个凹槽中设置移动导辊：外套由前外套和后外套两部分合成，该前、后外套分别安装在导向梁两侧，各开有可设置导辊轴的安装孔，     

铜基粉末冶金摩擦片的研究现状与展望

重载及特种车辆传动装置一般采用基于铜基粉末冶金材料的换挡摩擦片,随着传动装置向高转速、大扭矩、重载等方向发展,传统摩擦片性能不足的问题逐渐暴漏出来,如摩擦层脱落、芯板断裂等重大问题。针对铜基摩擦片日益凸显的重大问题,分析了摩擦片的发展过程及铜基摩擦片的应用现状,介绍了铜基摩擦片的构成形式与材料成分,阐述了摩擦片常见的失效形式与使用要求。进一步,从成分设计、制造过程、结构设计及后处理强化等方面提出针对性策略,指出铜基摩擦片多工艺耦合优化及开发新型环保复合材料摩擦片将会是摩擦片发展的重要方向。     

石钢Y15M高硫高磷易切削钢的冶炼试制

Y15M高硫高磷易切削钢具有易切削、易攻丝的优点,主要用于制造汽车螺栓、弹簧座等部件.简述了Y15M钢生产的技术难点、试制过程、精炼渣系的设计及控制,分析了精炼和连铸过程中的气体含量、连铸坯的夹杂物级别及其组成,为进一步完善生产工艺提供了重要依据.     

丝锥用HYTV3高性能高速钢的耐磨性和可磨削性评价

介绍了河冶科技自主研发的丝锥用3V级HYTV3高性能高速钢与国外某厂3V级高速钢的性能。通过合金化设计、精准化工艺控制,HYTV3高速钢获得细小均匀的MC碳化物组织。通过改变磨削加工类型、砂轻材质、砂轮转速参数,对比了M2、HYTV3、M3、GV3、M35五种材质的耐磨性和可磨削性,证明HYTV3高速钢在保持良好耐磨性的同时具有优异的可磨削性。     

铝电解时、阳极外套对电流效率、电解质粒子的运动、气体析出等的影响的研究

澳大利亚墨尔本市的矿山工程及建筑学院进行了该项研究。这一实验为实验室规模．铝的电解在一新型电解槽中进行．它包括1个可湿性阴极和1个加有外套的阳极。实验对在一定的熔融冰晶石的成分范围内．采用阳极外套时的铝电解工艺特点进行了探索。所用电极的面积为～5cm2．电量达24000库仑，电解的电流密度为1A／cm3。当电解质中熔融盐率不高时．电流效率＞94％．比工业生产中的电流效率高。阳极加有外套与无外套相比，它减少了阳极上电解金属产品与气体的接触，电流效率可提高～2％。若阳极与阳极外套间的距离控制得当．当熔盐率为1．14～1．…     

低温稀土硫氮共渗

本文研究了低温稀土、硫、氮三元共渗的工艺特点,组织和性能等。利用电子钟分析发现,在较低温度下,稀土元素可以渗入钢的表面,并对稀土的渗入机理进行了研究。实际应用表明,经该工艺处理后,M0.7机用丝锥的使用寿命可提高4—8倍。     

粉末冶金法修复铜基摩擦材料

摩擦片在高速、高温和高频率离合下工作,耗量非常大,造成很大的经济损失.本文采用粉末冶金的方法,对铜基摩擦片进行修复与再制造.通过将混合好的原料粉末放置于清洗与镀锡后的待修复摩擦片,再进行热压,使粉末在烧结的同时结合于待修复摩擦片.修复样品结合良好,进行摩擦磨损试验后未发生待修复层与粉末烧结层的分离.修复样品的成分及微观组织与待修复样品基本一致;其平均硬度值为89.4 Hv,最大摩擦系数为0.129,平均摩擦系数为0.112,均与待修复摩擦片接近.     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)