共查询到18条相似文献,搜索用时 250 毫秒
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三偏心蝶阀由于其适用温度压力范围广、切断性能好以及使用寿命长等突出优点,常用来替代传统的闸阀、截止阀和球阀,在以往很多其他阀门难以取得良好使用效果和难以保证安全性的场合,已有很多成功的应用实例。 相似文献
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《机电新产品导报》2002,(12)
中国·江南阀门有限公司致力于阀门新产品的开发研制取得卓越成效,分别在上海、浙江、北京设有子公司,在国内设立了50多家经销处和5个售后服务站,同时在国外巴黎和科威特等地设立了办事处。目前公司拥有员工300余人,阀门技术人员和专家50多人,大中型机加工设备近百台,注册资金融市场5000万元,年产能力1. 2亿元,分别通过ISO 9001和AP16D认证。主要新产品有中压调节型四氟密封蝶阀,调节型金属密封蝶阀,高温调节型金属密封蝶阀,0.5s电液联动局面速关闭阀,变频调速阀,局面速关闭抽汽止回阀,液压缓闭金属密封封止回阀,防火型截止、节流、止回多功能阀,双向金属硬密封球阀和普通闸阀、截止阀、节流阀、球阀等近万能胶种产品。企业素以综合技术开发能力强、产品更新换代局面而闻名中外。 相似文献
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Installing a flow conditioner is an important method for rectifying irregular and unstable flow to stable flow state within a short flow distance in fluid transportation and control industrial applications. However, classical flow conditioners (such as Laws and Zanker flow conditioners in ISO 5167) with parallel pipeline axial orifices ineffectively rectify the distinct eccentric jet flow caused by valve regulation. The convergence flow conditioner with convergent orifices was innovatively designed for rectifying the eccentric jet flow caused by a ball valve in this study. Three convergent orifice angles (8°, 10°, and 12°) defined as angles between orifice and pipeline axes were considered to compare their effect on eccentric jet flow rectification as well as with the classical Laws flow conditioner (characterized by the convergent orifice angle of 0°) under different valve openings with an experimental setup for monitoring downstream pressures that develop along the pipeline and corresponding numerical simulation used. Pressure loss and throttling effect of installing convergence flow conditioners downstream the ball valve was assessed. Analysis of distributions of the pressure, velocity, and streamline for convergent flow conditioners showed that the flow conditioner with a large convergent orifice angle can effectively improve violent eccentric jet flows, especially under a small valve opening. The axial velocity on various downstream cross sections was extracted to evaluate the velocity uniformity. A dimensionless parameter of velocity eccentric ratio was used to quantify the rectification effect of eccentric jet flow evolving in the downstream pipeline. Results showed that a short pipeline length is needed to obtain additional symmetry and uniform flow field downstream of the flow conditioner with a high convergent orifice angle, that is, the convergence flow conditioner with a high convergent orifice angle demonstrated a strong effect of flow rectification on the valve-induced eccentric jet flow. This work can help understand characteristics of flow rectification on valve-induced eccentric jet flow in scientific research, and provide guidance for the flow conditioner design in fluid engineering. 相似文献
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V形球阀是一种性能优良的调节阀,但在一定条件下会发生空化,从而对管路造成损害。为了研究截流面积对V形球阀内部流动的影响,通过数值模拟的方法,对V形球阀在空化与非空化工况下的内部流场进行了研究,同时对比分析了不同锥角和不同开度下V形球阀流量特性、阻力特性、空化特性的变化规律。结果表明:V形球阀的流量系数随开度和锥角的增大而增大,且阻力系数随着开度和锥角的增大而减小;V形球阀的能量损失随着锥角的增大而减小;随着开度的增大,V形球阀流道内的空化程度减小。研究为V形球阀的应用与设计优化提供了理论依据。 相似文献
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采用数值模拟和实验研究相结合的方法,研究阀芯行程对角座阀流量特性的影响。将阀芯行程为10 mm和14 mm时阀内介质流量的测试数据和数值计算结果进行对比,验证了数值模拟的准确性。在此基础上,对不同行程条件下阀内的速度场、压力场和流动旋涡进行分析。结果表明:随着阀芯行程的增加,阀门出口处的低压区域逐渐向下游移动,阀内的高流速区域更集中,流动旋涡更规则;因此,在较大的行程条件下,阀内介质的流动稳定性更好,流动阻力更小,具有更高的流量系数;在阀芯弹簧受力允许的条件下,应尽可能增加阀芯行程,提高阀门流通能力。 相似文献
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Gates are important hydraulic structures and used for flow measurement, water delivery, and water level regulation in open channels and irrigation networks. In this study, the quarter-circular gate is introduced and investigated. The cross section of this gate consists of a quarter circular arc and the lip angle of the gate equals to zero. Discharge coefficient, variation of downstream flow depth, and velocity distribution at opening section of gate were experimentally measured. Using potential flow theory supported by dimensional analysis, equations for discharge coefficient and velocity distribution at gate opening section of quarter-circular gate were derived and then validated using experimental data. The mean percentage error (MPE) of obtained equation for discharge coefficient of quarter-circular gate was calculated as 2.24%, indicating the high precision of the proposed theory. Based on obtained results, downstream flow depth of quarter-circular gate is uniform. Also, velocity distribution at gate opening section is nearly uniform. Discharge coefficient of quarter-circular gate was averagely obtained 55% larger than that of sluice gate. It was also obtained larger than that of radial gate. Elimination of contraction section at downstream of gate opening, which is the main source for energy loss and therefore discharge capacity reduction, is the main reason for larger discharge coefficient of quarter-circular gate. 相似文献