截止阀是一种常用的截断阀，主要用来接通或截断管路中的介质，一般不用于调节流量。截止阀适用的压力、温度范围很大，但一般用于中、小口径的管道。
截止阀的主要优点：
1）与闸阀相比，截止阀的结构较简单，制造与维修都较方便。
2）密封面不易磨损、擦伤，密封性较好，寿命较长。
3）启闭时阀瓣行程较小，启闭时间较短，阀门高度较小。
主要零件材料及性能规范
| 主要零部件 | 阀体 阀盖 | 碳钢 | 铬镍钛不锈钢 | 铬镍钼钛不锈钢 | 超低碳不锈钢 | 铬钼合金钢 | 低温碳钢 | ||
| 阀瓣 阀座 | 碳钢堆焊硬质合金或不锈钢 | 铬镍钛不锈钢 堆焊硬质合金 | 铬镍钼钛不锈钢 堆焊硬质合金 | 超低碳不锈钢 | 铬钼合金钢 堆焊硬质合金 | 不锈钢堆焊硬质合金 | |||
| 阀杆 | 铬不锈钢 | 铬镍钛不锈钢 | 铬镍钼钛不锈钢 | 超低碳不锈钢 | 铬钼合金钢 | 不锈钢 | |||
| 填料 | 石墨石棉盘根 | 浸聚四氟乙烯石棉盘根 | 柔性石墨石棉盘根 | 浸聚四氟乙烯石棉盘根 | |||||
| 垫片 | 石棉垫片 | 不锈钢带四氟乙烯缠绕垫片 | 柔性石墨+不锈钢 | 聚四氟乙烯 | |||||
| 阀杆螺母 | 高镍球铁/ZguAL10Fe3 | ||||||||
| 主要参数 | 适用介质 | 水、蒸汽、油品 | 硝酸类 | 醋酸类 | 尿素、甲铵液等 | 水、蒸汽、石油及石油产品 | 氨气、液氨 | ||
| 适用温度℃ | ≤425 | ≤200 | ≤200 | ≤200 | ≤550 | -45～150 | |||
| 型号 | 公称 通径 NPS(in) | 压力级 Class | 主要结构尺寸(mm) | 阀体 材料 | 性能规范 | ||||
| Do | D | L | H | 适用温度(℃) | 适用介质 | ||||
| SFJ | 2" | 150 | 200 | | 203 | 380 | WCB | ≤425 | 蒸气、油品、水等 |
| " | 3" | " | 250 | | 241 | 465 | " | " | " |
| '' | 4" | " | 300 | | 292 | 530 | " | " | " |
| " | 6" | " | 350 | | 406 | 650 | " | " | " |
| " | 8" | " | 400 | | 495 | 760 | " | " | " |
| " | 10" | " | 500 | | 622 | 860 | " | " | " |
| " | 12" | " | 600 | | 699 | 1000 | " | " | " |
| " | 14" | " | 600 | | 787 | 1050 | " | " | " |
| " | 16" | " | 750 | | 914 | 1150 | " | " | " |
| SFJ | 2" | 300 | 200 | | 267 | 425 | WCB | ≤425 | 蒸气、油品、水等 |
| " | 3" | " | 250 | | 318 | 530 | " | " | " |
| " | 4" | " | 300 | | 356 | 610 | " | " | " |
| " | 6" | " | 400 | | 445 | 790 | " | " | " |
| " | 8" | " | 500 | | 559 | 870 | " | " | " |
| " | 10" | " | 500 | | 622 | 1040 | " | " | " |
| " | 12" | " | 600 | | 711 | 1140 | " | " | " |
| " | 14" | " | 750 | | 838 | 1200 | " | " | " |
| " | 16" | " | 850 | | 864 | 1400 | " | " | " |
| SFJ | 2" | 600 | 250 | | 292 | 475 | WCB | ≤425 | 蒸气、油品、水等 |
| " | 3" | " | 300 | | 356 | 585 | " | " | " |
| " | 4" | " | 350 | | 432 | 675 | " | " | " |
| " | 6" | " | 450 | | 559 | 885 | " | " | " |
| " | 8" | " | 500 | | 660 | 945 | " | " | " |
| " | 10" | " | 600 | | 787 | 1040 | " | " | " |
| " | 12" | " | 750 | | 838 | 1280 | " | " | " |
| " | 14" | " | 850 | | 889 | 1350 | " | " | " |
| " | 16" | " | 960 | | 991 | 1550 | " | " | " |
注：焊接坡口尺寸按相关标准或按用户要求执行。
