一、结构及用途 Structure and purpose
该阀主要用于管路系统中，以防止管路系统超压或维持管路的压力，当泵关闭后还可以减少水锤冲击。也可用于大型供水系统的水锤消除装置，并且阀门控制系统的进口处装有一个自清洗滤网，利用流体特性，使比重较大、直径较大的悬浮颗粒不会进入控制系统，确保主阀的上游供水压力某一设定值上使系统循环畅通无阻，该阀起闭灵敏、安全可靠、动作平稳、使用寿命长。
Use in a pipeline system to prevent it from surpassing pressure or keep the pressure of it．to reduce the water hammer's shock after the pump is closed and also and also used as a water hammer remover for a large water supply system．On the inlet of the valve's control system a self cleaning filter screen is placed，which，by means of the bigger specific gravity of the fluid，stops the suspension grains of a bigger specific gravity and diameter going into the sys-tern to ensure the main valve's water supply pressure at the upstream at a set value to get the system smoothly circulated without any resistance．This valve features sensitive open-close，safety，reliability，stable motion and long duration.
四、主要外形及连接尺寸 Schematic diagram of installation
| 公称通径 DN(mm) | 20 | 25 | 32 | 40 | 50 | 65 | 80 | 100 | 125 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 |
| L | 180 | 180 | 180 | 203 | 203 | 216 | 241 | 292 | 330 | 356 | 495 | 622 | 698 | 787 | 914 | 978 | 978 |
| PN10 | D | 105 | 115 | 135 | 145 | 160 | 180 | 195 | 215 | 245 | 280 | 335 | 390 | 440 | 500 | 565 | 615 | 670 |
| D1 | 75 | 85 | 100 | 110 | 125 | 145 | 160 | 180 | 210 | 240 | 295 | 350 | 400 | 460 | 515 | 565 | 620 |
| PN6 | D | 105 | 115 | 135 | 145 | 160 | 180 | 195 | 215 | 245 | 280 | 335 | 405 | 460 | 520 | 580 | 640 | 705 |
| D1 | 75 | 85 | 100 | 110 | 125 | 145 | 160 | 180 | 210 | 240 | 295 | 355 | 410 | 470 | 525 | 585 | 650 |
| PN25 | D | 105 | 110 | 135 | 145 | 160 | 180 | 195 | 230 | 270 | 300 | 360 | 425 | 485 | 550 | 610 | 660 | 730 |
| D1 | 75 | 85 | 100 | 110 | 125 | 145 | 160 | 190 | 220 | 250 | 310 | 370 | 430 | 490 | 550 | 600 | 660 |
| H | 550 | 550 | 550 | 610 | 610 | 625 | 645 | 750 | 808 | 864 | 1135 | 1185 | 1325 | 1385 | 1445 | 1325 | 1430 |
| H1 | 460 | 460 | 460 | 516 | 516 | 520 | 538 | 596 | 655 | 710 | 805 | 855 | 955 | 990 | 1030 | 905 | 960 |
注：安装示意图中弹性座封闸阀或蝶阀任选，建议≥ DN350选蝶阀。
Note：Either elastic seat ring sealed gate valve or butterfly valve can be selected in the schematic diagram of installation.Recommended to select the butterfly valve in case of≥DN350
