带钢热轧机支承辊磨损控制数学模型的开发

带钢平直度的精度取决于几个因素;轧辊磨损是影响带钢表面质量的主要变量之一。轧辊磨损源于复杂的摩擦条件,因为带钢不与支承辊接触,有时没有分析支承辊磨损;但几个轧制周期之后,因为压力分配不均匀,支承辊磨损就变得很危险了。研究带钢热轧机支承辊表面劣化对开发带钢热轧机板形自动控制系统而言是非常重要的。根据两个轴线平行的圆柱体之间的Hertz压力分布开发了一个数学模型。实时使用该模型来计算支承辊磨损,并据此来防止支承辊过度磨损造成成品返工或损坏设备的事故。     

起重机钢丝绳磨损报废测量方法初探

钢丝绳是起重机的三大安全装置之一,钢丝绳的报废标准有断丝的性质和数量,绳端断丝,断丝的局部聚集,断丝的增加率,绳股断裂,绳径减小,包括从绳芯损坏所致的情况,弹性降低,外部和内部磨损,外部和内部锈蚀,变形,由于受热或电弧的作用引起的损坏,永久伸长率等。其中外部磨损规定当外层钢丝磨损达到其直径的40%时,钢丝绳应报废。当钢丝绳直径相对于公称直径减小7%或更多时,即使未发现断丝,该钢丝绳也应报废。现场无法准确确定,其他报废标准现场都能直观的判断。起重机常用钢丝绳外层钢丝直径为0.6mm~4.4mm,直径太小,磨损量40%更是不能精确判断。下面就根据本人多年来对起重设备的维护和检修,在钢丝绳外层磨损报废标准判定方面的一些经验。     

穿管机顶头的热磨损

从穿管机顶头在生产中容易发生塌鼻、粘钢和开裂等损坏现象,试验分析出热磨损、粘着磨损和低周疲劳是钢基顶头损坏的三种基本原因,在现阶段生产中,热磨损是尤为普遍的主要损坏原因,由此提出研制复合材料顶头的设想。     

穿管机顶头的热磨损

从穿管机顶头在生产中容易发生塌鼻、粘钢和开裂等损坏现象,试验分析出热磨损、粘着磨损和低周疲劳是钢基顶头损坏的三种基本原因,在现阶段生产中,热磨损是尤为普遍的主要损坏原因,由此提出研制复合材料顶头的设想。     

油膜轴承的损坏原因及其修复方法

分析油膜轴承损坏的诸多原因,包括磨损损坏、污染损坏、装配缺陷损坏、结合缺陷损坏和过热损坏。在总结实践经验与数据分析基础上,对损坏轴承提出了现场修复与专业厂家修复方法,并重点介绍专业厂家修复的几种方法。     

表面工程技术及应用

表面工程技术是一门边缘科学技术。其应用范围十分广泛,在近代科学和工业生产的实践中,更显示出这一新技术具有极其旺盛的生命力和巨大的经济技术意义。 物体表面的磨损和腐蚀是使物体失效和破坏的主要形式。机械零件的损坏形式,一般可分为两类;第一类为非正常损坏。当零件在受到拉伸、压缩、弯曲、扭转、剪切、冲击等外力作用时而引起开裂、折断,或发生超过允许范围的变形。产生这种形式损坏的原因是由于设计不合理,或加工制造质量不     

兴澄特钢3200m~3高炉风口损坏原因及应对措施

对兴澄特钢3200m~3高炉风口损坏的原因及应对措施进行了阐述。风口损坏的统计数据表明,3200m~3高炉风口损坏的主要形式是熔损(占损坏总数的75.70%)和磨损(占损坏总数的16.82%),认为风口前端熔损的主要原因是炉缸活跃程度差,风口内孔磨损的主要原因是煤枪插入角度过大。并从风口设计及制造、高炉生产操作两方面,提出了延长风口寿命的一些应对措施。     

国外黑色冶金

一些处理或运送磨蚀性物料(砂子、石灰石、矿石、煤等)的机器和设备,其零件受到相当大的磨损,以致很快损坏而不能继续使用。磨蚀性物料作用于零件工作面的条件是多种多样的,Аверин曾提出如下的磨损分类: (1)破碎时的冲击磨损; (2)磨碎时零件承受负荷引起的磨损; (3)在轻微力的作用下零件的擦伤。对于具体零件,耐磨材质的选择应按不同的磨损特性来确定。当零件是在高速冲击负载条件下工作(圆锥破碎机和     

轴承钢冶金质量和工艺选择

滚动轴承损坏的原因很多,例如疲劳、磨损、塑性变形、润滑不良、污垢、装配不当和轴承带电等。如果轴承的装配和维护是合适的话,轴承损坏的原因主要是疲劳造成的。滚动轴承产生疲劳,一般是,当在滚动件和与其接触的表面上存在夹杂、孔洞或偏析时,在周期性交变应力作用下,首先以缺陷为核心,形成裂纹,逐步扩展为鳞片状剥落,在轴承的滚道或滚动体的表面形成麻     

微机保护装置的容错功能

微机保护装置内部元件损坏时，从可靠性的角度希望任一元件损坏时保护不应误动，同时能自动检测出故障元件并报警，以便得到及时处理，防止设备或线路故障时由于元件损坏未被及时处理造成保护拒动。     

渣包车大臂举升速度下降的故障分析及排除

主要阐述了K350SH60型渣包车的基本构造,大臂举升液压控制系统的工作原理、介绍了大臂举升系统的故障现象、以及大臂举升速度下降的可能原因,并对液压系统的斜盘式变量泵、液压油缸、LS阀、平衡阀、主溢流阀与电液换向阀、大臂举升系统工作电路进行分析及排除故障的一些措施。     

铜电解系统循环泵机械密封泄露的原因与防治

分析了铜电解系统循环泵机械密封失效的原因,介绍了防治循环泵机械密封泄露和磨损的措施及实施效果。     

铜电解系统循环泵机械密封泄露的原因与防治

分析了铜电解系统循环泵机械密封失效的原因，介绍了防治循环泵机械密封泄露和磨损的措施及实施效果。     

Integrating Equation of Gradually Varied Flow

This paper presents an improvement in the direct method originally proposed by Chow for integrating the equation of gradually varied flow in prismatic channels. The hydraulic parameters assumed to be constants at all depths by Chow are introduced in the integration as variable parameters. The differential equation of gradually varied flow is integrated, considering the effect of variable parameters. The results obtained by this improved method compare well with the results of the numerical method. The advantage of this method over the existing method is that acceptable accuracy is obtained in only one step for a wide range of cases.     

泵站水力机械抗气蚀耐磨损工艺研究

在多泥沙（黄河水源）抽水站水力机械使用过程中,除正常的泥砂和机械磨损外,其过流断面以及本体受气蚀的危害,严重影响水力机械运行工况,提高了能源单耗。经过多年的实践,在水力机械过流部件上涂耐磨材料,可以大大提高水力机械使用寿命,降低运行成本。     

Disturbance of continuous, pump administration of cardiovascular drugs by hydrostatic pressure

Administration of highly concentrated, highly potent, and therefore highly dangerous drugs with syringe pumps is common in modern anaesthesia as well as in intensive care and emergency medicine. Because of their exact flow rates down to < 1 ml/h, these pumps are predestined for delivery of drugs with short half-lives, such as catecholamines and vasodilators. But intravenous application of drugs with syringe pumps is not without problems. While it is well known that syringes not fixed correctly into the pump can empty themselves by the influence of gravity, it seems not to be known that hydrostatic pressure can influence the flow rate of a correctly connected system even during continuous infusion. In this situation a change of height of the syringe pump in relation to the patient's position can have tremendous effects on hemodynamics due to unintended acceleration or deceleration of the flow rate. This case report demonstrates that the elevation of a connected epinephrine pump while moving a cardiac surgery patient after ACB operation from the operation table into his bed led to critical increases of heart rate, blood pressure and left atrial pressure. In order to quantify the problem we repeated the situation experimentally. It could be demonstrated that the elevation of the syringe pump by 80-100 cm delivers an additional bolus of 4-5 drops as the central venous catheter outlet. Lowering the pump consecutively leads to the opposite effect. In the case reported, the accidentally administered bolus of epinephrine was 12-15 micrograms (we use a concentration of 60 micrograms/ml epinephrine for continuous infusion with syringe pumps). From this accidental observation the following conclusion can be drawn: The change of height, in relation to the patient's position, of a running syringe pump during continuous infusion of highly concentrated cardiovascular drugs may cause considerable, even life-threatening hemodynamic disorders. Even in a closed infusion system (syringe-extension-central venous catheter), hydrostatic pressure influences infusion rate. Elevation of the pump leads to unintended bolus administration, and lowering of the pump is followed by an interruption of the infusion. In the knowledge of this phenomenon, unexpected hemodynamic reactions during transport of critically ill patients cannot always be interpreted as a result of inadequate anesthesia or volume load, but may be a consequence of incorrect handling of the syringe pumps as described in this report.     

Production of Structure Components with Selective Properties by means of Action Media based Cold Forming

Minimising a metallic component's weight can be achieved by either using lightweight alloys or by improving the component's properties. In both cases, the material formability affects the utilisability for mass production processes. Most of the high‐strength materials show a material‐restricted formability and are difficult to forge. The formability of a material is described by its maximum forming limit. Large plastic strains can lead to mechanical damage within the material. A promising approach of handling low ductile, high‐strength alloys in a forming process is deformation under superimposed hydrostatic pressure by active media. In the present study, the influence of superimposed hydrostatic pressure on the flow stress is analysed as well as the forming ability for different sample geometries at different hydrostatic pressure and temperature levels. The experimental results show that the superimposed pressure has no influence on the plastic deformation, nor does a pressure dependent near‐surface material hardening occur. Nevertheless, the formability is improved with increasing hydrostatic pressure. The relative gain at room temperature and increase in the superimposed pressure from 0 bar to 600 bar for tested materials was at least 140 % and max. 220 %. Therefore, a cold forming process under superimposed pressure is developed to produce structure components with selective properties. For example, the gain in formability will be used to enlarge local plastic strains to higher limits resulting in higher local strain hardening and hardness. This offers new design possibilities with selectively adjusted local structure or structure component properties, especially adapted to their technical application. Additionally, by applying damage models, finite‐element analysis is used in order to predict damage occurring in the cold forming process under superimposed hydrostatic pressure for various sample geometries.     

液压系统噪音产生的原因与降噪技术

本文通过对广钢双膛石灰窑液压系统在生产运行过程中的噪音和振动原因进行了分析，认为柱塞泵的噪音是液压系统噪音产生的主要原因，而柱塞泵出口的流量脉动和压力脉动则是造成次级噪音的原因。并提出解决问题的途径之一是采用具有P—Q控制降噪新技术的柱塞泵，认为这种柱塞泵能够更有效地减少柱塞泵泵体产生的噪音量以及柱塞泵出口流量脉动和压力脉动引起的次级噪音量。     

A10VSO型恒压变量轴向柱塞泵典型故障分析与处理

主要阐述了A10VS0型恒压变量轴向柱塞泵的工作原理及无流量和压力输出的液压故障分析与相关处理方法。     

负荷传感技术在重型平板车液压控制系统上的应用

重型平板车的控制系统大多采用全液压控制系统,近年来,负荷传感液压系统作为一种先进的液压技术在重型平板车上展现了其应用趋势,在介绍了变量泵负荷传感系统原理的基础上,针对某型号重型平板车的工艺要求,设计开发了具有节能、高效和可控性能高的转向与悬挂液压控制系统。