二片式内外螺纹球阀用于分流或汇合流通，是具有二面或四面阀门的多通口球阀，任何一通口可用作入口而无泄漏。
主要零件材料Materials of main parts
| 零件名称 Description of parts | Q21F-(16-64)C | | |
| | | | |
| 阀盖Bonnet | WCB | ZG1Cr18Ni9i CF8 | ZG1Cr18Ni12Mo2Ti CF8M |
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| | 聚四氟乙烯Polytetrafluorethylene(PTEE) |
| | 聚四氟乙烯Polytetrafluorethylene(PTEE) |
| 二片式内外螺纹球阀主要外形尺寸Main outer size |
| DN | G | d | L | M | E | Φ | H | W |
| 8 | 1/4" | 8 | 85 | 20x1.5 | 15 | 22 | 40 | 105 |
| 10 | 3/8" | 8 | 85 | 24x1.5 | 16 | 26.5 | 42 | 105 |
| 15 | 1/2" | 10.5 | 85 | 30x2 | 18 | 31 | 45 | 110 |
| 20 | 3/4" | 13 | 90 | 36x2 | 18 | 37 | 48 | 110 |
| 25 | 1" | 17 | 100 | 42x2 | 20 | 43 | 43 | 110 |
| 32 | 1¼" | 22 | 120 | 52x2 | 20 | 53 | 64 | 135 |
| 40 | 1½" | 26 | 135 | 60x3 | 25 | 62 | 75 | 160 |
| 50 | 2" | 32 | 140 | 72x3 | 25 | 73 | 79 | 170 |
