西班牙研製波浪（làng）發電裝置（zhì） 2009年（nián）將放入海中運行

　　為了（le）正確選擇自（zì）動控製閥的（de）通徑，用戶需要了解下（xià）列（liè）事項：
　　To properly size an automatic control valve you need to know the following:

• *高和*低的進口壓力
  Highest and Lowest inlet pressures
• 出口壓力
  Outlet pressure
• *大流量要求
  Maximum flow requirements
• *小（xiǎo）流量要求
  Minimum flow requirements

　　步驟1：利用高流量表，並且在橫軸上（shàng）找（zhǎo）出符合用戶*大流量要求的流量值。
　　Step 1: Utilize the high flow chart and select the flow as found on the horizontal axis which corresponds with your maximum flow requirements.
　　步驟2：從這一點劃垂線，延伸到與（yǔ）相應的*小壓差的水平線相交。（此時，*小壓差將是*低進口壓（yā）力減去所需要的出口壓力，這（zhè）也就是所說的（de）∆P。）
　　Step 2: From this point draw a vertical line until you intersect with the horizontal line corresponding with the minimum differential pressure. (Your minimum differential pressure will be the lowest inlet pressure minus the desired outlet pressure, this is also known as the delta P.)
　　步（bù）驟3：從這一點向右移動直到**個閥門的通徑線。這就是（shì）在（zài）25英（yīng）尺/秒間歇流（liú）量時應該采用的*小閥門通（tōng）徑。如果*大流量是連（lián）續（xù）的，那麽不要超過*大連續（xù）流量（liàng）表上所列的美製加侖/分鍾（20英尺（chǐ）/秒）。
　　Step 3: From this point move right to the first valve size line. This will be the minimum valve size which should be used on intermittent flow of 25 ft./sec. If maximum flow is continuous, then do not exceed the GPM (20 FT./sec.) listed on the maximum continuous flow table.

　　步驟4：利用流量表，在豎軸（zhóu）上找到*大壓差。（用戶的*大壓差將是*高進口壓力減去所需要的出口壓力，這也就是所說的∆P。）
　　Step 4: Utilize the flow chart and select the maximum differential pressure as found on the vertical axis. (Your maximum differential pressure will be the highest inlet pressure minus the desired outlet pressure, this is also known as the delta P.)
　　步驟5：從這一點劃水平線與步驟3選擇的閥門通徑相應（yīng）的線相交。
　　Step 5: From this point draw a horizontal line until you intersect with the line corresponding to the valve size as selected in step 3.
　　步驟（zhòu）6：從這一點（diǎn）劃垂線向下與橫軸相交。這就是以這些變量（liàng）為基礎的閥門的*小流量能力。
　　Step 6: From this point draw a vertical line down to the horizontal axis. This will be the minimum flow capabilities of the valve based on these variables.
　　注意：1) 如果（guǒ）通過步（bù）驟6得到的*小流量能（néng）力比用戶實際的*小流量要求（qiú）高，則用戶應該考慮采用並聯安（ān）裝方式（shì）。采用這個*小流量（liàng）能力，從（cóng）步驟1開始選擇用戶（hù）需要的用於低流量旁路的通徑（jìng）。
　　　　　2) 采用空**表並且確（què）定進口和出口壓（yā）力的相交是否落在陰影區域內。如果（guǒ）是（shì），用戶應該考慮串聯安（ān）裝方式（shì）。兩個閥門都應該按照上述步驟選擇通徑。
　　Notes: 1) If the minimum flow capability obtained from step 6 is above your actual minimum flow requirements, you should consider a parallel installation. Using the minimum flow capability, begin at step 1 to select the size you will need for this low-flow by-pass.
　　　　　2) Use the cavitation chart and determine if the intersection of the inlet and outlet pressures falls in the shaded area. If so, you should consider a series installation. Both valves should be sized in accordance with the above steps.

壓降指數 - 減壓閥
PRESSURE DROP INDEX - PRESSURE REDUCING VALVES

　　通過從*大（dà）進口壓力減去所需要的出口壓力來（lái）計算壓差。找出壓差線上的數字，並（bìng）且注意出口壓力指數。這是不會落入空穴區的*低的出口壓力設置。美（měi）國瓦茨自動控製閥的結構將可能導致空穴現象的閥門損壞潛在（zài）危險降低（dī）到（dào）*小程度。避（bì）免在空穴區域內（nèi）持續運行。
　　Calculate the pressure difference by subtracting the desired outlet pressure from the maximum inlet pressure. Find the number on the pressure difference line and note the outlet pressure index number. This is the lowest outlet pressure setting allowed without failing into the cavitation zone. Design of the WATTS Automatic Control Valve minimizes potential valve damage that can be caused by cavitation. Avoid continued operation within the cavitation zone.

空**表
CAVITATION CHART

　　閥門通徑選（xuǎn）擇後，在這個圖表中找出進口和出口壓（yā）力。如果交點落在陰影區域，則可能產（chǎn）生空穴。應該避（bì）免在空穴區域內持續運行閥門。請谘詢美國瓦茨ACV，了解其他解決方案。
　　After selecting valve size, locate inlet and outlet pressures on this chart. If the intersection point falls in the shaded area, cavitation can occur. Operation of valves continually in the cavitation zone should be avoided. Consult Watts ACV for alternatives.