高扬程酸洗离心泵密封改造案例

离心泵是目前应用范围最为广泛的通用型设备之一,在氧化铝生产流程中具有非常重要的作用,因而保证离心泵的稳定运行是生产顺利进行的前提和保证,本文介绍了氧化铝生产流程中溶出管道化工序高扬程离心泵密封改造应用,以及离心泵轴封常用的两种密封方式和并根据密封改造过程、步骤的案例分析介绍了两种密封的应用及优缺点。     

浅谈离心泵的故障诊断方法

本文针对离心泵的常见故障，提出了从性能参数、振动频率及烈度、轴承、轴封、管路系统、润滑油、冷却水等几方面是否正常来判断故障的所在位置、类型，并列举了工程中的实例加以说明．     

CQF型氟塑料合金磁力驱动离心泵

江苏江风氟合金泵阀制造公司制造的CQF型氟塑料合金磁力驱动离心泵,是中国第43号专利产品,适用于-30℃～ 108℃温度条件下长期输送各种强腐蚀介质,特别是输送昂贵和剧毒溶液尤能显示该泵的优越性能。无需轴封,永不泄漏,彻底解决了用户在使用过程中的跑、冒、滴、漏之环境污染问题。     

集装式机械密封泄漏拆检分析

目前离心泵的轴封最主要的密封装置就是机械密封,而且随着机械密封应用范围的不断扩大,机械密封的结构形式也不断的得到完善,集中式机械密封就是其中之一,本文结合大型渣浆泵的集装式机械密封故障的实例,对损坏泄漏的集装式机械密封进行了拆检,并分析了机械密封的故障原因,根据机械密封泄漏的原因制定了相关的处理措施。     

钛磁力泵在宝鸡有色金属加工厂研制成功

据有关资料介绍，化工商心泵的故障47％发生在轴的机械密封部位，38％发生在轴承和泵的填料函部位，泵在运行半年后，大约有40％～50％的填料和机械密封失效．可见轴封是离心泵最薄弱的环节，是离心泵安全、可靠运行的关键．无论是传统的填料密封，还是比较先进的机械密封都不可能做到无泄漏．磁力驱动泵（简称磁力泵）是利用磁感应原理传递扭矩，将电动机输出的力矩传递给叶轮，以达到输送介质的目的．该泵最大的特点是将系的动密封变为静密封，旋转轴不在外部露出，完全无泄漏．由于钛有不被磁化和优异的耐蚀特性，因此钛磁力泵得到了很大…     

C（M）630型煤气鼓风机轴端气封改造

针对C（M）630型煤气鼓风机轴封漏煤气的问题,从轴封结构、维修技术、使用寿命等方面考虑,采用迷宫密封＋氮气辅助密封的形式进行改进,解决了轴封漏煤气的安全隐患。     

V型轴封环的试验研究

本文论述了轴贯穿部分Ｖ型轴封环的结构和装配方式，通过大量试验得出了安装使用的重要参数；唇尖安装压缩量和转轴对轴封环的相对过盈量。为Ｖ型轴封环的可靠运用和生产ＩＰ５４、ＩＰ５５电机解决了重要的技术难题。     

改造汽轮机的轴封系统以维持机组的真空

为维持机组真空,低压缸轴封供汽就会漏出汽缸;调小机组轴封供汽导致机组真空急剧下降。通过改造机组轴封系统,减少轴封漏汽同时维持机组真空。     

15MW汽轮机轴封磨损原因分析及处理

介绍了宣钢公司动力厂15 MW汽轮发电机组轴封磨损原因分析及处理,通过检修及工艺优化,解决了困扰汽轮机轴封磨损问题,为快速恢复机组的安全运行积累了经验。     

煤气鼓风机气封改造实践

针对煤气鼓风机轴封处泄漏煤气的现象,通过对轴封结构的分析研究和实验论证,将鼓风机的气封方式由自吸式密封改为高压氮气强制密封,取得了很好的效果,消除了风机房内CO浓度高的安全隐患。     

非接触式机械密封技术在氧化铝生产料浆泵中的应用

分析氧化铝生产料桨泵轴封失效原因，通过现场测量计算与分析，将双端面流体润滑非接触式机械密封成功应用于氧化铝生产用料浆泵的轴封，实现了料浆泵介质的零泄漏。     

水泵轴封改进试验

剖析了水泵盘根密封在生产实践中存在的问题及所造成的危害，探索水泵密封的改进途径。通过无填料轴封在水泵上的试验情况进行分析、评价，介绍在本单位试验体会。     

离心泵机械密封的泄漏与故障分析

机械密封在泵类设备中应用广泛,但泄漏问题普遍存在,直接影响着设备运行的安全性和稳定性。根据实际检修经验及相关理论,系统总结了机械密封比较常见的故障,详细分析了离心泵发生泄漏的原因,并提出了解决措施。     

离心清水泵填料密封的技术改造

析了离心清水泵原用盘根密封性差的主要原因,从经济和节能两个方面考虑,采用一种新型密封材料,既减轻了维修成本又为企业带来巨大的经济效益。     

An implantable centrifugal blood pump for long term circulatory support

A compact centrifugal blood pump was developed as an implantable left ventricular assist system. The impeller diameter is 40 mm and the pump dimensions are 55 x 64 mm. This first prototype was fabricated from titanium alloy, resulting in a pump weight of 400 g including a brushless DC motor. Weight of the second prototype pump was reduced to 280 g. The entire blood contacting surface is coated with diamond like carbon to improve blood compatibility. Flow rates of over 7 L/min against 100 mmHg pressure at 2,500 rpm with 9 W total power consumption have been measured. A newly designed mechanical seal with a recirculating purge system ("Cool-Seal") is used as a shaft seal. In this seal system, seal temperature is kept under 40 degrees C to prevent heat denaturation of blood proteins. Purge fluid also cools the pump motor coil and journal bearing. The purge fluid is continuously purified and sterilized by an ultrafiltration filter incorporated into the paracorporeal drive console. In vitro experiments with bovine blood demonstrated an acceptably low hemolysis rate (normalized index of hemolysis = 0.005 +/- 0.002 g/100 L). In vivo experiments are currently ongoing using calves. Via left thoracotomy, left ventricular apex-descending aorta bypass was performed utilizing a PTFE (Polytetrafluoroethylene) vascular graft, with the pump placed in the left thoracic cavity. In two in vivo experiments, pump flow rate was maintained at 5-8 L/min, and pump power consumption remained stable at 9-10 W. All plasma free hemoglobin levels were measured at < 15 mg/dl. The seal system has demonstrated good seal capability with negligible purge fluid consumption (< 0.5 ml/ day). Both animals remain under observation after 162 and 91 days of continuous pump function.     

鄂钢5号连铸机立式离心泵的故障分析及改进

针对立式离心泵在实际运行过程中出现的问题,制定了轴承箱冷却、联轴器调整、机械密封调整等改进措施,措施实施后,提高了设备的作业率,减少了设备的运行成本,降低了检修人员劳动强度,改善了现场环境。     

动能自控密封器在烧结离心风机上的应用

济钢烧结厂烧结离心风机原采用迷宫加羊毛毡密封，因磨损出现轴承座漏油的问题。为此，安装使用了KH-6动能自控轴密封器，该密封器基于“以疏治漏”的理念，可使润滑介质在轴间径向摆振，伴随轴速形成S状轨迹软密封。应用表明，动能自控轴密封器彻底解决了风机润滑油的渗、漏问题，效果稳定，运行安全，仅节油一项年省费用达几十万元。     

Control of centrifugal blood pump based on the motor current

In this study, centrifugal pump performance was examined in a mock circulatory loop to derive an automatic pump rotational speed (rpm) control method. The pivot bearing supported sealless centrifugal pump was placed in the left ventricular apex to aorta bypass mode. The pneumatic pulsatile ventricle was used to simulate the natural ventricle. To simulate the suction effect in the ventricle, a collapsible rubber tube was placed in the inflow port of the centrifugal pump in series with the apex of the simulated ventricle. Experimentally, the centrifugal pump speed (rpm) was gradually increased to simulate the suction effect. The pump flow through the centrifugal pump measured by an electromagnetic flowmeter, the aortic pressure, and the motor current were continuously digitized at 100 Hz and stored in a personal computer. The analysis of the cross-spectral density between the pump flow and motor current waveforms revealed that 2 waveforms were highly correlated at the frequency range between 0 and 4 Hz, with the coherence and phase angles being close to 1.0 and 0 degree, respectively. The fast Fourier transform analysis of the motor current indicated that the second harmonic component of the motor current power density increased with the occurrence of the suction effect in the circuit. The ratio of the fundamental to the second harmonic component decreased less than 1.3 as the suction effect developed in the circuit. It is possible to detect and prevent the suction effect of the centrifugal blood pump in the natural ventricle through analysis of the motor current waveform.     

离心机承口密封结构的改进

离心机承口密封频繁失效,且失效后检修难度大、更换费时费力,为此,改进离心机承口结构和承口密封圈挡环材质,使密封效果提高,密封圈寿命提高了近2倍,并缩短了检修时间,提高了铸管生产产量。     

Importance of pre-treatment radiation absorbed dose estimation for radioimmunotherapy of non-Hodgkin''s lymphoma

We have been developing a new type of centrifugal pump for long-term use. The magnetically suspended centrifugal pump (MSCP) contains no shaft and seal so that long life expectancy is predicted. Paracorporeal left ventricular (LV) assist circulation between the left atrium and the descending aorta was instituted using sheep. The flow rates ranged from 2.5-5.5 L/min. The sheep that lived the longest (46 days) died of an embolism as a result of the thrombus in the pump. No thrombus formation was observed in other pumps. Plasma free hemoglobin levels ranged from 9 to 18 mg/dl, which led to the conclusion that the hemolysis level remained within an acceptable range. Two driving modes were compared. The slope of the pressure-flow relationship plot under a constant motor current mode was steeper than that under a constant rotational speed mode, and thus, the flow fluctuation decreased. In conclusion, the MSCP is durable for more than a month at the current stage of development and is a promising device for long-term ventricular assist.