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调节阀的选型和参数定义   发布时间:17-04-06

调节阀的选型和参数定义


ZMAP/ZMBP 气动薄膜单座调节阀是自动控制系统中最常用的执行器,它由气动薄膜执行机构和低流阻调节阀组成。单座适用于对泄露量求严格、阀前后压差低及有一定粘度和含纤维介质的场合;双座阀不平衡力小、允许压差大、流通能力大等特点,适用于泄露量要求不严格的场合;套筒阀具有稳定性好,不易产生震动,噪音低,对温度敏感小,适用于压差较大及泄露量要求不严格场合。

ZDLP电子式电动单座调节阀由3810L型(或PSL系列)直行程电动子式执行机构和直通单座阀组成。内含伺服功能,接受统一的4-20mA或1-5V·DC的标准信号,将电流信号转变成相对应的直线位移,自动地控制调节阀开度,达到对管道内流体的压力、流量、温度、液位等工艺参数的连续调节。 

单座阀适用于对泄露量求严格、阀前后压差低及有一定粘度和含少量纤维介质的场合。广泛应用于电力、冶金、化工、石油、环保、轻工、设备等行业。

V230W型自力式温度调节阀主要由控制阀及温控器组成,是一种无需外来能源而依靠被控介质自身的温度变化进行自动调节的节能产品。主要适用于非腐蚀性气体、蒸汽、热水、油等介质的各种换热器中的温度自动控制,广泛应用在城市供热、供暖系统及石化、印染、制药、锅炉等工业部门。本系列产品由公称压力PN16、40,公称通径15~200mm,温度调节范围从0到270℃,多种多样的品种可供选择。

ZMAP-16D 气动低温单座调节阀是单座、双座的变形产品。它与常温不同之处在于采用长颈型上阀盖,使填料处于常温下工作。适用于-60~-250℃低温壮态下的介质(如液氧、液氮等)的调节。为确保调节精度,必须配用定位器。

ZDRV电动V型调节球阀是一种芯阀座采用金属,或金属对聚四氟乙烯密封配合的旋转球阀,它将球阀和蝶阀的最佳控制特性结合成一体,既可用作控制调节阀,又可作关断切断阀。适用于高粘度、悬浮液、纸浆等不干净、含纤维介质场合。


ZDRV电动V型调节球阀--特点

 

(1)不带任何管接头的整体式阀体,因此不受管道或螺栓应力影响,并且由于阀体无任何管接头,故耐压壳体不会受压力“突变”的影响;
(2)具有一个V型阀体,即使在小流量或高粘度介质的情况下,也可在整个量程范围内,保证控制的精确性;
(3)防漏耐用的阀座在其外径处衬有带不锈钢内芯PTFE杯形或是O型密封圈,阀座用截面较大的钨钴硬质合金制成,通过一个合金的波纹弹簧进一步增强了阀座的结构;
(4)当阀门关闭时,V型缺口与阀座之间产生楔形剪切作用,并既具有自洁功能又可防止球芯卡死,特别适用于管线结垢冻结或含有纤维和颗粒固体场合。

ZAZM电动套筒调节阀,由DDZ型直行程电动执行机构和精小型套筒阀组成。与伺服放大器组合接受统一的4-20mA或0-10zA·DC)的标准信号,将电流信号转变成相对应的直线位移,自动地控制调节阀开度,达到对管道内流体的压力、流量、温度、液位等工艺参数的连续调节。

电动套筒调节阀--主要特点:

 

1、采用平衡型阀芯,不平衡力下,允许压差大,操作稳定。

 

2、阀芯导向面大,可改善由涡流和冲击引起的振荡。

 

3、比普通的单、双座调节阀噪声降低10dB左右。

 

4、结构简单,装拆维修方便。


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