磁致伸缩液位计的原理结构及应用

磁致伸缩液位计是近几年才在国内兴起的一种新型液位计。由于工作性质的原因,笔者也是近两年才接触到这种液位计,在工程设计和实际使用中积累了一些经验。笔者简单的介绍一下磁致伸缩液位计的基本原理与结构并结合精细化工生产中的实例,探讨其在工程实践中的应用。     

浅谈雷达液位计故障处理与分析

雷达液位计能够精确测量易燃、强腐蚀性等介质液位,同时具有连续测量精度高的优点,同时还具有非接触式以及测量范围大等特点,因此这种测量仪表在化工工业中得到了非常广泛的应用.由于其工作的特殊性,雷达液位计需要在强腐蚀环境下连续工作,这就大幅度提高了雷达液位计故障发生的概率,文章结合江西蓝恒达化工有限公司液氯储槽应用实例,浅谈...     

原油分离器磁浮子液位计的现场校准

磁浮子液位计作为原油分离器的液位显示仪表,是反应分离器运行是否正常的主要依据之一。在油田生产中,原油分离器是使用较多的一种压力容器,是用于单井来油进行汇集、分离原油、天然气和水和计量。若液位计出现示值、远传误差,就会造成分离器油线串气或气线串油,不仅影响原油处理系统的正常生产,还会对油井计量精度造成误差。通过对原油分离器磁浮子液位计使用中的探索总结,对原油分离器磁浮子液位计的日常维护内容进行了探讨,对原油分离器磁浮子液位计的介质密度、显示校准和信号输出校准方法进行了研究。     

聚酯蒸馏釜液位监控方案

通过浮筒式液位计以及输入产出估算法实现了蒸馏釜的全程液位监控，间接论述了粘稠介质液位的检测思路。     

食用油油罐液位雷达测量技术

雷达液位计是一种新型的液位测量技术,不仅应用在化工、油田领域,而且也可以应用在食品工业中测量各种储罐液位.联合利华公司下属的希腊ELAIS食用油工厂在液位测量中选择了萨伯-罗斯蒙特雷达液位计,成功地解决了困难环境下的精确测量难题.     

数字式电接点液位计电阻易位的效果

DYS－19型数字式电接点液位计，主要用于电站锅炉监控汽包水位。它显示直观醒目，功能齐全，输出0～10mA直流电流，可直接与DDZ-Ⅱ型仪表配套使用，完成指示、记录、调节各种功能；并有越限报警（±50mm）和满水、缺水保护控制（±200mm）输出。因此，被广泛使用。我厂有4台65t/h中温中压锅炉，均采用DYS－19型数字式液位计。该仪表在使用中出现了一些问题，主要是在锅炉冷态启动和安全阀动作时指示失准、重影等。为此，笔者分析了液位计的测量电路，经过反复试验，找出了原因，并作了相应改进，经长期运行证明，取得了预期效果。仪表使…     

浮筒液位计测量误差的来源及处理方法

文章简要阐述了浮筒液位计的测量原理,结合实际应用对其测量误差的来源作了较详细的分析,针对各种误差的特性,指出了它们的影响方式、范围及程度,并提出相应的消除或抑制方法。     

智能伺服液位计的液位管理系统的应用

介绍了重庆耐德东京计装仪表有限公司生产的FW-9智能伺服液位计、DIR罐边显示器和ATS多点平均温度计和CATAMS液位管理系统及其应用。     

吹液法液位计在蒸发罐液位测量中的应用

介绍了吹液法液位计和吹液装置的测量原理,结合现场实际应用分析存在问题及提出改进措施.     

超声波液位计的原理与应用

超声波液位计是一种非接触式液位测量仪,可用于测量各种容器或管道内的液位高低和流量大小,也可以用于水池、水渠、水库、江河湖海水位的测量,测量精度高,安装维护方便,可以同时测量水位、水位差和流量等,并具有计算机标准RS-485接口等特点,因此得到愈来愈广泛的应用。     

用百分表测金属丝的杨氏弹性模量

简要介绍了用百分表测钢丝杨氏弹性模量的原理及方法 ,同时阐明了此方法的主要优点 ,并将此法的测量结果与传统测量光杠杆法的结果作了进一步比较 .     

苎麻牵切隔距与皮辊加压的关系分析

主要分析了新型牵切机皮辊加压量和牵切隔距的关系，通过拉伸机牵断纤维束测得纤维的平均强度，然后根据纤维的摩擦系数得出皮辊对纤维束的压力与牵切隔距的关系式，在牵切机上实验加以验证关系式的合理性。     

集聚纱与非集聚纱的轴向应变及其对纱线拉伸性能的影响

通过试验重点研究了轴向应变对集聚纱拉伸性能的影响。拉伸性能主要涉及断裂强度、断裂伸长和断裂功。选择不同的应变速率和纱线夹持长度,对9.7 tex集聚纱和非集聚纱进行拉伸测试,然后根据Meredith试验过程绘制不同应变速率和夹持长度条件下各自的负荷-伸长曲线,同时测量各曲线三个区域的斜率。测试结果表明：两种9.7 tex的纱线（集聚纱和非集聚纱）随着应变速率的增加,断裂强度均增加,但当断裂伸长增加到一定程度,且在较高应变速率下,断裂强度有所下降;两种纱线随着夹持长度的增加,断裂强度和断裂伸长均降低;两种纱线的斜率随着应变速率的增加均增加,但随着夹持长度的增加而下降。试验还发现,非集聚纱的斜率变化较大,而集聚纱的斜率变化较小。     

Measuring the strength of knotted suture materials

There is no international standard method for measuring the strength of knotted suture materials, and although several methods have been published, there has been minimal investigation on the effects of test variables on measured properties (e.g. speed, gauge length, and knot tensioning force). Methods investigated in this work were the “ear method” (with and without a rod inside the loop), and the “cut-loop and ear method”. The test environment, material, and type of knot were constant. Effects of varying gauge length, test speed, and knot-tensioning force on tenacity and strain were investigated and compared with data for nonknotted sutures. Different values of tenacity and strain were evident for the different test methods; lower values of tenacity for specimens with shorter gauge lengths and tested at greater speeds; lower values of strain for specimens with longer gauge lengths and tested at greater speeds. Thus, tensile properties of suture materials tested at one gauge length or one test speed, as widely reported in the literature, may be misleading. Knot tensioning force neither affect tenacity nor strain.     

FA224梳棉机后上罩板隔距对生条结杂短绒的影响

为了解后上罩板与锡林间的隔距对生条结杂短绒的影响,在一定的工艺设备、不同的后上罩板与锡林间隔距条件下,纺制了不同的生条.通过对这些生条的测试可知:后上罩板与锡林隔距的大小对生条质量影响明显,隔距放大后,生条中棉结、杂质降低,短绒减少,生条质量得到改善.     

模切机后靠规定位误差的分析

对模切机后靠规定位机构在槽凸轮远休止段定位时的定位误差进行了定性和定量分析,给出了随着机器工作速度的提高,后靠规定位误差有增大趋势的结论,并着重指出在满足机器模切精度的范围内,尽量避免某个特殊转速的结论.     

Length of small gauge zone between cylinder and flat of a card

The length of small gauge zone (SGZ) between cylinder and flat of a card was studied mathematically. A formula to calculate the length was derived with geometry and calculus methods, by which the abscissa of the point at which the flat–cylinder gauge was minimal was obtained. The effect of heel–toe difference (HTD), cylinder radius, flat setover, minimum flat–cylinder gauge, as well as the difference between outlet gauge and minimum flat–cylinder gauge on the length of SGZ was discussed, respectively. It is concluded that a smaller cylinder radius, smaller HTD and a longer flat setover will help to lengthen SGZ. Given an appropriate value of the difference between the outlet gauge and the minimum gauge, δ, a longer SGZ will be beneficial to improving the carding intensity. But the influence of δ and the minimum flat–cylinder gauge on the length of SGZ can be ignored. The conclusion is of some theoretical value for manufacturers of textile accessories or machinery to accurately choose parameters such as cylinder radius, HTD and setover in production.     

Effect of gauge length on loop strength of sewing threads

Seam strength prediction using loop strength has been found to be more accurate and has been consistently used by researchers over last few decades. But the testing gauge length for loop strength has not been standardized as in the case of thread tensile strength. In this paper, effect of gauge length on thread tensile strength and elongation in loop form and straight form has been studied. 40 tex and 60 tex mercerized cotton and spun polyester threads are used for the study. It is observed that there is no significant change in the loop strength of the threads as the gauge length increases, whereas the tensile strength of all threads decreases with the increase in gauge length. Elongation % is found to change significantly in both loop and straight form during tensile testing. Therefore, it is concluded that loop strength tests can be carried out at any gauge length unlike tensile testing of straight threads.     

梳棉机锡林—回转盖板隔距与梳理质量

为了提高生条质量,减少盖板落棉,分析了锡林与回转盖板的梳理原理,对比了标准盖板与非标准盖板对条干、棉结杂质及锡林—盖板隔距与质量的关系,探讨了降低盖板总高误差及锡林—盖板隔距变化的方法。指出：锡林—盖板隔距增大使生条结杂增多、短绒率降低,当隔距增大0.025mm时生条质量恶化,增大0.051mm时生条严重恶化;锡林—盖板隔距和刺辊工艺优化组合,生条棉结降低25.6%,短绒率降低0.65%、棉结降低35.5%,条干CV值降低0.07个百分点;隔距的准确性、稳定性关系到质量与节棉的双重效益;减小盖板针布总高误差及隔距差异,有利于设备更好地发挥工艺特性,取得质量和节棉双赢。     

静电板电压和隔距对生条棉结的影响

 在梳棉机的后罩板处加装自制的静电型棉网清洁器,对不同静电板隔距和电压下生产的生条分别进行了AFIS检测。结果表明,该装置在适当的隔距和电压下可以降低生条中棉结的含量和尺寸。当静电板与锡林间的隔距为1 mm时,1500 V电压是相对有效的,棉结的含量和尺寸分别比不加电压时降低6.9%和5.7%;带籽屑棉结含量和尺寸分别降低42.9% 和 4.0% 。当隔距为2 mm时,4000 V电压是更有效,棉结的含量和尺寸分别降低8.7% 和5.5%,带籽屑棉结的含量分别降低25% 和4.3% 。当隔距为3 mm时,在本文试验的各种电压下,棉结和带籽屑棉结的含量和尺寸没有改善。