截止閥是一種常用的截斷閥，主要用來接通或截斷管路中的介質，一般不用于調節流量。截止閥適用的壓力、溫度范圍很大，但一般用于中、小口徑的管道。
截止閥的主要優點：
1）與閘閥相比，截止閥的結構較簡單，制造與維修都較方便。
2）密封面不易磨損、擦傷，密封性較好，壽命較長。
3）啟閉時閥瓣行程較小，啟閉時間較短，閥門高度較小。
主要零件材料及性能規范
| 主要零部件 | 閥體 閥蓋 | 碳鋼 | 鉻鎳鈦不銹鋼 | 鉻鎳鉬鈦不銹鋼 | 超低碳不銹鋼 | 鉻鉬合金鋼 | 低溫碳鋼 | ||
| 閥瓣 閥座 | 碳鋼堆焊硬質合金或不銹鋼 | 鉻鎳鈦不銹鋼 堆焊硬質合金 | 鉻鎳鉬鈦不銹鋼 堆焊硬質合金 | 超低碳不銹鋼 | 鉻鉬合金鋼 堆焊硬質合金 | 不銹鋼堆焊硬質合金 | |||
| 閥桿 | 鉻不銹鋼 | 鉻鎳鈦不銹鋼 | 鉻鎳鉬鈦不銹鋼 | 超低碳不銹鋼 | 鉻鉬合金鋼 | 不銹鋼 | |||
| 填料 | 石墨石棉盤根 | 浸聚四氟乙烯石棉盤根 | 柔性石墨石棉盤根 | 浸聚四氟乙烯石棉盤根 | |||||
| 墊片 | 石棉墊片 | 不銹鋼帶四氟乙烯纏繞墊片 | 柔性石墨+不銹鋼 | 聚四氟乙烯 | |||||
| 閥桿螺母 | 高鎳球鐵/ZguAL10Fe3 | ||||||||
| 主要參數 | 適用介質 | 水、蒸汽、油品 | 硝酸類 | 醋酸類 | 尿素、甲銨液等 | 水、蒸汽、石油及石油產品 | 氨氣、液氨 | ||
| 適用溫度℃ | ≤425 | ≤200 | ≤200 | ≤200 | ≤550 | -45～150 | |||
| 型號 | 公稱 通徑 NPS(in) | 壓力級 Class | 主要結構尺寸(mm) | 閥體 材料 | 性能規范 | ||||
| Do | D | L | H | 適用溫度(℃) | 適用介質 | ||||
| SFJ | 2" | 150 | 200 | | 203 | 380 | WCB | ≤425 | 蒸氣、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 | 蒸氣、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 | 蒸氣、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：焊接坡口尺寸按相關標準或按用戶要求執行。
