译文：
一、活塞式流量调节阀的特点及工作原理： 德国VAG 阀门公司生产的RKV、RKV RIKO活塞式流量调节阀。活塞式流量调节阀与只用作管线切断的蝶阀和闸阀不同，活塞阀是能满足各种特殊调节要求的阀门。其调节功能是靠一类似于活塞状圆柱体在阀腔内作轴向运动来实现的，它的行程与管内水流方向是一致的。水流从轴向弧状进入外壳，活塞阀内的流道为轴对称形，流体流过时不会产生紊流。流道面积的改变是通过一个活塞沿管道轴向做直线运动实现。无论活塞在何位置，阀腔内的水无论活塞运动到任何位置，阀腔内无论任何位置的水流断面均为环状，在出口处向轴心收缩，从而达到{zj0}防气蚀，从而避免因节流而可能产生的气蚀对阀体和管道的破坏。 活塞阀阀体设计成一个整体，具有高流通能力，开度与流量成线性关系，能有效地避免气蚀和震动。内壳有流线型的导流肋和外壳相连，不锈钢活塞被可靠导引滑动，杜绝产生倾斜或运行不畅。内壳上游的端面成球形，使水流形成一个渐变过程，活塞用安装在壳内的曲柄连杆来操作。活塞阀采用金属对金属及金属与橡胶双重密封，实现双向气泡级密封。因此从而达到密封系统使用寿命长，关闭严密。 由于活塞阀的结构特殊，根据运行工况的不同，阀的过水特性可以用阀下游出水口出口部件的型式来调节（可更换出口部件），从而适应不同目的的工况要求，达到{zj0}的调流效果。 二、活塞式流量调节阀的应用： 出口调节型部件有四种： 1、{dy}种E型，具有截弯取直和沿端座下游横截面突然放大结构，从而xx气蚀破坏。适用于控流，高压差，背压大的场合，而截弯取直，横截面突然放大结构可以减小气蚀效应。 2、第二种S型，其关闭的导向部件有开槽的套筒。适用于控流、调节高压差及足够的背压大的场合，它的调节性与流体状态匹配，可以达到较佳的效果。 3、第三种F型，在阀体出口部分具有短扩散管作用，适用于调节及启闭场合，起到开关作用。启闭时水头损失非常小，xx开启时阻力小。 4、第四种LH或SZ型，在阀腔内的活塞关闭的导向部件安装了有防气蚀的多孔环网，适用于调节、防气蚀、高压差、背压小（蓄水池入口处），它的控流调节特性和运行工况要求{zj0}匹配，从而达到了xx气蚀效应。 5、VAG活塞阀在引水方面可以用作泄放阀和防爆管阀，在贮存时VAG活塞阀LH型、E型可以用作液位或压力调节阀，在输水上VAG活塞阀LH型、S型可以用作流量调节阀，E型，LH型或SZ型可用作放净阀或灌管阀，在污水、水处理VAG活塞阀可以用作泵启动保护阀，或是配备特殊的调节出口部件，也可以用在水处理厂的流量调节阀，E型活塞阀亦可以用作污水处理厂气量调节阀，在供水上VAG活塞阀根据液态工况采用不同的出口部件，用作压力/流量调节阀，例如管网压力平衡。

“Piston valves for the working principle and application ”是由提供的国际阀门新闻，译文仅供参考。另外，中国调节阀网还提供相关产品搜索：、、、、等。

原文：
1, piston-type flow control valve of the characteristics and working principle: German VAG valves produced RKV, RKV RIKO flow control valve piston. Flow control valve and piston used only for pipelines to cut off the valve and gate valve different from the piston valve is adjusted to meet the requirements of various special valves. The regulatory function is by a similar piston-like cylinder for axial movement in the valve chamber to achieve, and its direction of travel and the flow tube is the same. Water into the shell from the curved axial piston valve inside the flow channel axis symmetrical shape, fluid flow out of date will not generate turbulence. Changes in flow area of a piston by a straight line along the pipe axis to achieve. No matter in what position the piston, valve piston cavity of the water regardless of any position, any position regardless of valve chamber are circular flow cross section, the exit to the axis of contraction, so as to achieve the best anti-cavitation, thus avoiding savings which may arise due to cavitation erosion of the valve and pipe damage. Piston valve body designed as a whole, with high flow capacity, opening a linear relationship with the flow, can effectively prevent cavitation and vibration. Diversion within the shell has streamlined ribs and shell connected by a reliable guide sliding stainless steel piston, tilt, or eliminate the production run sluggish. Within the upper end into a spherical shell to form a gradual process flow, piston rod installed in the shell of the crank to operate. Piston valve metal on metal and metal and rubber double sealing, two-way bubble level seal. Therefore, to achieve the long life sealing system, close tightly. Since the special structure of the piston valve, according to different operating conditions, characteristics of the valve over the water downstream of the outlet valve can export parts of the pattern to adjust (to replace the export components), which aims to adapt to different conditions required to achieve the best of adjusting flow effect. 2, piston valves for applications: There are four components of Regulating Type: 1, the first E-type, with straighter and downstream along the side seat suddenly enlarged cross-sectional structure, thereby eliminating the cavitation damage. Applicable to flow control, pressure differential, back pressure big occasions, but straightened, suddenly enlarged cross-section structure can reduce cavitation effects. 2, the second S-type, the closed-oriented components are slotted sleeve. Apply flow control to regulate the pressure difference and big enough back pressure of the occasion, its regulatory match and fluid state, can achieve better results. 3, the third F-type, the body part of a short-proliferation export control role for regulation and gate occasions, play a role switch. Open and close when the head loss is very small, completely turned resistance. 4, fourth LH or SZ type, in the cavity of the piston valve closed oriented components installed with anti-cavitation of the porous ring for adjustment, anti-cavitation, pressure differential, back pressure is small (reservoir entrance ), its regulation and flow control characteristics and operating conditions best match the requirements, so as to achieve the elimination of cavitation effect. 5, VAG piston valve in the water that can be used as a relief valve, and explosion-proof pipe valve, piston valve in the storage of LH when the VAG-type, E type can be used for liquid level or pressure regulating valve, piston valve in the water on the VAG LH type S-type can be used as flow control valve, E-type, LH type or SZ type can be used as a net release valve or irrigation pipe valve, sewage, water treatment VAG piston valve can be used to start the pump protection valve, or with a special regulation Export parts also can be used in the flow control valve water treatment plants, E-type piston valve can also be used as a sewage treatment plant volume control valve, piston valve in the water on the VAG liquid conditions under different export components for pressure / flow control valve, such as pipeline pressure balance.