原文：
               在给水泵站中，为使离心泵轻载启动，通常要求先关闭泵的出口阀门，再启动水泵机组，当其转速达额定转速以后，再逐渐打开出口阀门；为了防止系统中介质倒流，还必须在泵的出口安装止回阀；由于普通旋启式止回阀的瞬时关闭常产生危及水泵系统的水锤事故，所以还要设置有效的水锤消除装置。

　　目前较多采用的是电动蝶(闸)阀配套微阻缓闭止回阀来实现上述目的，但在现场使用中电动蝶（闸）阀常出现关闭不严，电机烧坏和齿轮减速传动机构损坏等故障：微阻缓闭止回阀适应范围窄，不能适应流量、压力的较大变化， Safety Relief Valves且其调节针阀易阻塞，导致阻尼器不能动作等故障，影响正常安全供水。

　　一、多功能水泵控制阀简介　　多功能水泵控制阀是一种新型水力控制阀门，一阀可替代电动蝶(闸)阀、止回阀和水锤消除器三种装置。它能自动实现开泵时的缓开，停泵时的速闭与缓闭，无需任何电气控制与其它动力和人力，也无需油压装置。　　多功能水泵控制阀的主要优点有：　

　（1）　无需操作控制。利用水泵启停时阀门前后的水压差作为控制动力，具有随水泵的启闭而自动启闭的功能。

　　（2）　阀门启闭动作过程能有效地因防止水锤压力波升高而产生的事故。据现场使用情况调查和实测，停泵水锤压力峰值均在工作压力的1．3倍以内。

　　（3）　无需现场调试，适用工况范围广。

　　（4）　基本无需维修。由于一阀替代三阀，维护维修工作量大大减少。

　　（5）　阻力损失小。采用流线型、宽阀体设计，阻力损失比国外同类产品降低50％以上，如DN200产品在v=2m／s的经济流速工况时，Instrumentation Ball Valves多功能水泵控制阀损失为0．7m,而国外同类产品为1．5m。

　　二、多功能水泵控制阀的结构及工作原理　　2．1　结构　　多功能水泵控制阀结构参见图1，由主阀及外装附件组成。主阀包括阀体、主阀板、缓闭阀板、阀杆、阀座以及膜片控制器（含阀盖、膜片座、膜片、膜片压板）：外装附件有控制阀、过滤器、排空阀、微止回阀。其中微止回阀是特制配件，在其止回方向设有限流孔。安装形式参见图2。 2.2 工作原理　　水泵启动前，阀门出口端压力作用在主阀板上，阀门处于关闭位置，同时膜片控制器的上腔连通压力水，下腔则与阀门进口端的低压相通。　　水泵启动后，阀门进口压力逐渐升高，同时压力水通过阀门进口端的连接管缓慢进入膜片控制器下腔，实现主阀板的缓慢开启，开启速度可通过控制阀进行调节。

　　水泵停机，阀门进口的压力降低，当接近零流量时，主阀板在自身重力作用下迅速关闭。因阀门进口端压力降低，阀门出口端的压力水通过连接管进入膜片控制器上腔，下腔水通过阀门进口端的连接管压回至阀门进口端，缓闭阀板缓慢关闭，慢关时间可通过控制阀进行调节。主阀板的速闭和缓闭阀板的缓闭符合两阶段关闭规律，Balance Valves能有效地消除水锤。

 　　三、几个技术问题

　　3.1　连接管的部件设计　　微止回阀的作用是保证阀门开启的时间大于电机启动时间，使电机轻载启动；同时避免因开阀速度过快而导致启泵水锤。阀门开启时间可由控制阀根据现场工况压力设定。　　控制阀可调节进出膜片控制器上下腔的水流速度，从而调节缓闭时间；关闭时可检修膜片控制器；在水泵正常运行时也可手动操作该阀来启闭阀门。　　过滤器是保证膜片控制器上下腔中水的清洁度。由于阀门在一个开启过程水流是往复进出的，本身具有反冲洗的作用，因此也可用于介质较差的工况。　

　　　3．2阀门的消除水锤特性　　从产生破坏性水锤的原理可知，减小水锤升压主要有2个因素：(1)在刚被切断前的水流速度v尽可能小(接近于零)时关闭主阀板；(2)使闭阀历时t是水锤相u=2L／α(α--压力波传递速度，m／s；L--管长，m)的5-10倍，就可以把实际水锤压力h限定在安全范围内，从而消除破坏性的水锤危害。　　多功能水泵控制阀主阀板的开启度是由管道中的水流冲击力大小决定的，流速高时主阀板开启度大：流速减小时阀板开启度小：流速接近于零时，主阀板关闭。整个过程与消除水锤的速闭原理相吻合，因此消除水锤效果很好。　　多功能水泵控制阀缓闭阀板的关闭，必须在膜片式控制器上下腔形成压力差后方能实现，即主阀板关闭后，缓闭阀板方能关闭，因此不可能产生缓闭与速闭同步的现象。 　　3．3阀门的阻力特性　　为了减少水流阻力，设计中减轻了主阀板的重量，Needle & Gauge Valves同时采用了流线型宽敞的阀体设计。经湖南省水力机械质监授权站检测，DN200多功能水泵控制阀阻力系数约为3．8，而同规格管道的旋启式止回阀阻力系数值为5．5。

　　3．4膜片的设计　　膜片的质量是直接影响阀门使用效果和使用寿命的关键部件，经过多种筛选，选用了氯丁橡胶为原材料，中间用尼龙纤维网进行加强；经湖南省橡胶质监授权站检测，疲劳弯曲65万次无破裂，可使用10年以上。

　　3．5维修　　无其它外加液压或电动元件，基本无需维修，且采用宽型阀盖，可将阀内部件全部取出，维修方便。

　 　　四、实例　　安康铁路水厂工况为：扬程80m；高差68．4m；流量850 ／h；出水管口径DN400；管长为6km。使用 JD745X--10 DN400多功能水泵控制阀，据现场测试，缓闭时间为30s，停泵压力峰值为0．95MPa（原配置为电动蝶阀和微阻缓闭蝶阀，停泵压力峰值为1．2～1．4MPa）。停泵后水泵最大反转速度为600r／min，与原配置相同。

　　经理论计算，多功能水泵控制阀停泵压力峰值为0．98MPa，普通止回阀停泵压力峰值为1．88MPa。将多功能水泵控制阀、微阻缓闭蝶阀和普通止回阀三种Instrument Manifolds 设置情况正造成的停泵水锤结果列表比较如下：水锤边界条件 多功能水泵控制阀 电动蝶阀+普通止回阀 电动蝶阀+微阻缓闭蝶阀 Hmax/Ho 1.225 1.5 2.4 βmax/βo 0.4 0.4 　　　　　　　　　　　表1　　3种阀水锤边界条件比较 Hmanx—停泵压力峰值　Ho—正常工作压力　βmax—停泵后机组最大逆转速　βo—额定转速（1450r/min） 　　从上表可以看出，多功能水泵控制阀对于消除停泵水锤有明显效果，完全符合《泵站设计规范》以及《水泵操作规程》；多功能水泵控制阀还能实现启泵缓慢开启，能够消除开泵水锤。　　四、结语　　经过现场使用证明，多功能水泵控制阀能有效地消除破坏性水锤，在提高供水系统安全可靠性上有显著特点，并且便于调试及安装，便于操作管理，维修量少，符合《2000年城市供水行业技术进步发展规划》中对供水设备自动化、机械化和现代化的要求，是泵站更新换代的新型阀门产品。

“ Multifunctional Pump Control Valve in the security of water supply ”,是由中国电磁阀网提供的国际阀门新闻，译文仅供参考。另外，中国电磁阀网还提供相关产品搜索： 出口电磁阀、 防爆电磁阀、 蒸汽电磁阀、 液体电磁阀、 气体电磁阀、等。

译文：
          Water Pumping Station in order to start the pump light loads, often required to close the pump discharge valve, and then start the water pump, when its speed up to rated speed then, and then gradually open the outlet valve; to prevent the system from the media back must also be installed in the pump discharge valve; as ordinary swing check valve closure transient pumping systems often produce water hammer threatening accident, therefore I have set the effective elimination of water hammer device. More use of the electric current butterfly (gate) valve supporting micro Slow Close Check Valve to achieve these goals, but in the field using the electric butterfly (gate) valve closure often appear loose, the motor burned out and the gear transmission mechanism fault damage, etc.: to adapt micro Slow Close Check Valve narrow, can not meet the flow and pressure of major changes, and its adjustment needle easily blocked, leading to actions such as damper failure can not affect the normal safe water supply. I. Introduction Multifunctional Pump FILTER SERIESControl Valve Multifunctional Pump Control Valve is a new hydraulic control valve, a butterfly valve can replace the electric (gate) valve, check valve and water hammer eliminator three kinds of devices. It can automatically open when the pump slowly open, stopping the pump speed when closed and slow closed, without any control and other electrical power and manpower, no hydraulic device. Multifunctional Pump Control Valve The main advantages are: (1) without operator control. Before and after pump start and stop using the water pressure when the valve as the control power, with the opening and closing with the pump automatically open and close function. (2) the valve opening and closing movement process can effectively prevent water hammer due to increased pressureWATER POWER CONTROL VALVE wave caused by the accident. According to field investigations and the use of measurement, Water hammer pressure peaks were within 1.3 times the working pressure. (3) No on-site commissioning for a wide range of operating conditions. (4) basic no maintenance. As a three-valve replacement valves, maintenance and repair workload greatly reduced. (5) resistance loss. With streamlined, wide body design, pressure drop lower than similar foreign products more than 50%, such as DN200 products in the v = 2m / s flow rate of economic conditions, the multi-pump control valve loss of 0.7m, while similar products to 1.5m. Second, multi-functional water pump control valve of the structure and working principle 2.1 Structure Multifunctional Pump Control Valve structure see Figure 1, the main valve and the composition of exterior accessories. Main valve including the valve, main valve plate, slow closing valve plate, stem, seat and diaphragm control (including valve cover, diaphragm seat, diaphragm, diaphragm plate): exterior accessories have control valves, filters , emptying valve, micro valve. One micro check valve is specially designed accessories, located in the direction of its limited flow-return hole. Installation Type See Figure 2. 2.2 Work Before starting pump, valve outlet pressure valve in the main board, the valve is in closed position, while the upper chamber diaphragm controller connected pressure water, then with the valve cavity under low pressure inlet connected. Pump starts, valve inlet pressure gradually increased, while pressure water through the inlet valve of the connecting tube slowly into the cavity under the diaphragm control, the slow of master disc to open, open the speed through the control valve. Pump down, pressure reducing valve imports, when the near-zero flow, the main valve plate in its own gravity quickly shut down. Valve inlet pressure is reduced due to the valve outlet pressure water through the connecting pipe into diaphragm chamber controller, inferior vena water through the valve inlet connection pipe pressure back to the inlet valves, slow closing valve plate slowly closed off time can be slow through the control valve. Closing the main valve plate moderate speed slow closing valve closure plate closing law consistent with a two-stage, can effectively eliminate water hammer. Third, several technical problems 3.1 Design of connecting pipe parts The role of micro check valve is to ensure that the valve open time greater than the motor start-up time, start the motor at light loads; the same time to avoid too fast opening valve pump water hammer caused by the Kai. Valve open time by control valve pressure setting according to the site conditions. Diaphragm control valve controller can be adjusted up and down and out of cavity flow rate, thus adjusting slowly closing time; shut down when maintenance patch controller; the pump during normal operation can also manually operate the valve to open and close the valve. Membrane filter to ensure control of water in the upper and lower chamber cleanliness. As the valve is in an open flow back and forth and out of the process itself has a backwash effect, and therefore can be used for medium poor working conditions. 3.2 Characteristics of the valve to eliminate water hammer Damaging water hammer from the principle known, reducing the water hammer boost mainly two factors: (1) has just been cut off before the water velocity v as small as possible (close to zero), close the main valve plate; (2 ) to enable the valve closed duration t is the water hammer phase u = 2L / α (α - the pressure wave velocity, m / s; L - tube length, m), 5-10 times, you can put the actual water hammer pressure h limited to within the safe range, so the elimination of destructive water hammer damage. Multifunctional pump control valve plate open Fazhu degree water from the pipeline size impact the decision, the flow rate when the main valve plate to open the high degree: the flow rate decreases valve plate to open a small degree: the flow rate close to zero, the main valve Board closed. The whole process and eliminate water hammer principle of the speed close match, it works well to eliminate water hammer. Multifunctional Pump Control Valve relief valve plate closed off, the controller must be in upper and lower diaphragm cavity will be achieved after the formation of pressure difference, which close the main valve plate, the slow closing valve plate before being shut down, it can not produce close and slow fast close synchronization phenomenon. 3.3 The resistance of the valve In order to reduce the flow resistance design reduces the weight of the main valve plate, and spacious with a streamlined body design. Authorized by the Hunan Provincial Quality Supervision Station testing hydraulic machinery, DN200 multifunctional pump control valve resistance coefficient of about 3.8, while the same size pipe swing check valve resistance coefficient is 5.5. 3.4 Diaphragm Design Membrane will directly affect the quality of performance and service life of valve to use key components, through a variety of screening, use of chloroprene rubber as raw material, intermediate network to strengthen the use of nylon fiber; quality supervision authority station by the Hunan rubber testing, fatigue Bending 650 000 times without break, you can use more than 10 years. 3.5 Maintenance No other external hydraulic or electrical components, basic no maintenance, and the use of wide-type valve cover, valveBALANCING VALVES can be removed all the internal parts, and maintenance. 4, examples Ankang Railway Water conditions are: head 80m; elevation 68.4m; flow rate 850 / h; outlet pipe diameter DN400; tube length of 6km. Use JD745X - 10 DN400 multifunctional pump control valve, according to field test, slow closed time was 30s, stop the pump peak pressure 0.95MPa (originally configured Electric butterfly valve and micro-resistance butterfly valve, stop the pump peak pressure 1.2 ~ 1.4MPa). After the pump stopped pumping the maximum reverse speed 600r/min, and the original The same configuration. The theoretical calculation, multi-functional water pump control valve pressure pumping peak 0.98MPa, the pump stops ordinary check valve peak pressure 1.88MPa. Will be more Functional water pump control valve, micro-resistance check valve butterfly valve and the general situation is caused by three types of settings Water hammer results list are as follows: Multi-function pump water hammer control valve boundary conditions of ordinary check valve electric valve electricAPI CAST STEEL VALVES butterfly valve butterfly valve micro-resistance Hmax / Ho 1.225 1.5 2.4 βmax / βo 0.4 0.4 Table 1 three kinds of boundary conditions are relatively water hammer valves Hmanx-peak pressure pumping Ho-normal working pressure βmax-biggest reversal of Units after pumping speed βo-rated speed (1450r/min) As can be seen from the table, multifunctional pump control valve for the elimination of Water hammer is effective in full compliance with "Pumping Station Design Standards" and the "pumps operating procedure"; multifunctional pump control valve can achieve slow KaiFORGED STEEL VALVES pump open Open the pump to eliminate water hammer. IV Conclusion Through the use of that site, multi-functional water pump control valve can effectively eliminate the destructive water hammer, in improving the water supply system has significant security and reliability features, and easy to debug and installation, easy operation and management, maintenance less in line with "the city in 2000 Water Industry Development Plan technological progress "in Water supply equipment automation, mechanization and modernization, is the new pump station valve replacement product.

原文来源：http://www.diancifa.com/

2010-09-02 02:17

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