汽车油箱检漏系统的研制

采用气体压差原理研制了一种用于汽车生产中油箱密封性的智能检漏系统。在系统结构设计的基础上,又设计了其硬件电路、编写了软件,并采取了抗干扰措施。     

基于CPS-20B1智能控制器的恒压变频供水系统

采用CPS-20B1智能型变频调速供水控制器和变频器的恒压供水的控制策略,并自动地调整泵组的运行台数和电机的转速。利用内置的PID控制器调节变频器的输出,实现闭环自动调节、恒压供水。运行结果表明,该控制系统在管网流量变化时具有稳定供水压力,工作可靠和节约电能显著等特点。     

多功能天车液压系统无压力故障分析

介绍多功能天车液压站的组成及工艺要求；以打壳快速下降为例，论述液压系统工作过程；介绍液压系统无压力故障时的检查方法，分析造成液压系统无压力的原因，提出相应的预防措施。     

A Continuum Mechanics Approach for Crack Initiation and Crack Growth Predictions

Very often, different approaches are used for crack initiation and crack growth predictions. The current article introduces a recently developed approach that can be used for the predictions of both crack initiation and crack propagation. A basic assumption is that both crack nucleation and crack growth are governed by the same fatigue damage mechanisms and a single fatigue damage criterion can model both stages. A rule is that any material point fails to form a fresh crack if the total accumulated fatigue damage reaches a limit. For crack initiation predictions, the stresses and strains are obtained either directly from experiments or though a numerical analysis. For the prediction of crack growth, the approach consists of two steps. Elastic‐plastic stress analysis is conducted to obtain the detailed stress‐strain responses. A general fatigue criterion is used to predict fatigue crack growth. Compact specimens made of 1070 steel were experimentally tested under constant amplitude loading with different R‐ratios and the overloading influence. The capability of the approach to predict both crack initiation and the crack growth under these loading conditions was demonstrated by comparing the predictions with the experimental observations.     

应用改进的神经网络模型预报转炉冶炼终点

准确预报转炉冶炼终点的钢水温度与碳含量对提高转炉终点命中率具有重要意义。针对现有多层前馈网络学习算法的不足,基于BP模型提出一种改进算法,建立了复吹转炉冶炼终点的预报模型,并与BP模型的预测结果进行了统计比较。研究表明,改进后的模型能够对冶炼终点进行良好的预报。采用单节点输出模型对终点钢水碳含量与温度分别进行预报,预测误差w(Δ[C])<±0.03%的命中率达97.22%,Δt<±12℃的命中率为94.44%。还建立了神经网络双节点输出模型对转炉终点钢水碳含量及温度同时进行预报,误差Δt<±15℃、w(Δ[C])<0.03%的双命中率为76.92%。     

冷轧酸洗破鳞辊装置的失效分析与改进

宝钢分公司2030冷轧酸洗机组在开卷机处装配有一套破鳞辊装置用来提高酸洗效果.该装置投入使用后,由于破鳞辊处带钢跑偏严重、带钢张力波动过大,一直无法正常使用.通过对同步轴刚度的影响和位置闭环控制方式的分析,提出了改变破鳞辊压下的控制方式、增加破鳞辊的机械刚度、提高液压系统的响应速度等改进措施.实施后,破鳞辊引起的带钢跑偏问题得到解决,从而使酸洗机组工艺段的酸洗效率明显提高,工艺段速度提高8%,产能也相应得到了提高.     

(Cr1‐x,Alx)N ein Review über ein vielseitig einsetzbares Schichtsystem

(Cr_1‐x,Al_x)N a review about a multi‐purpose coating system Nitride based coatings claimed a big market share for PVD‐coatings. Especially in the field for high temperature die casting and cutting operations chromium based coatings are well used. These coatings are also used in low temperature processes for the coating of machine parts. In the beginning of the nineties first examinations are done on the ternary system Chromium‐Aluminium‐Nitride. This system shows an excellent corrosion behaviour against many different liquids, but gains also a high hardness for a good wear behaviour. By changing the AlN to CrN content and the coating design CrAlN opens up a wide range for different coating applications. A major step for machine parts was the reducing of coating process temperature beneath 200 °C. This was only possible by using pulsed power supplies. CrAlN shows a very good performance on the fast growing market of coated machine parts e.g. on spindle bearings.     

制备工艺对B4C/TiC/Mo陶瓷复合材料力学性能的影响

采用热压法制备了10%(质量分数)TiC/4.7%(质量分数)Mo增强B4C基陶瓷,分析了烧结温度、保温时间和烧结压力对力学性能的影响.烧结温度由1 800℃提高到1 900℃时,复合材料的抗弯强度由590MPa提高到705MPa;当烧结温度升至1 950℃,强度反而下降;硬度和韧度随烧结温度升高而提高.在烧结温度为1 900℃压力为35MPa保温时间由15min提高到45min时,抗弯强度由600MPa提高到705MPa;进一步增加保温时间,抗弯强度随保温时间的增加而下降;硬度和韧度随保温时间延长而提高.烧结压力对复合材料力学性能的影响较小.当烧结参数为1 900℃、45min、35MPa,B4C/TiC/Mo陶瓷复合材料抗弯强度、硬度、断裂韧度、相对密度分别为705MPa、20.6GPa、3.82MPa·m1/2、98.2%.     

太钢大型高炉炉顶均压控制

为了提高高炉冶炼系数,多出铁,减少能源消耗,企业通常尽量采用炉顶高压操作。大型高炉由于炉顶压力较高,在采用煤气一次均压后炉顶与料罐的压力差一般大于0.015 MPa,这就必须用氮气进行二次均压后才可以进行上料操作。本文简单介绍了太钢1 650 m3大型高炉与4 350 m3特大型高炉的炉顶均压控制原理。     

万家寨水电站调速器机械液压系统的故障分析及改造

分析了万家寨电站调速器机械液压系统存在的缺陷,采取了改造措施,提高了液压系统的可靠性。