A21 Micro Closed Spring Loaded Pressure Relief Valve
A21H spring micro-opening type external thread safety relief valve is suitable for equipment and pipelines with air, nitrogen, petroleum gas and other media whose working temperature is ≤200℃. A21W type is suitable for equipment and pipelines with working temperature ≤200℃ and containing corrosi...
A21H spring micro-opening type external thread safety relief valve is suitable for equipment and pipelines with air, nitrogen, petroleum gas and other media whose working temperature is ≤200℃. A21W type is suitable for equipment and pipelines with working temperature ≤200℃ and containing corrosive gas or liquid. Type A21F is suitable for equipment and pipelines such as liquefied petroleum gas and petroleum gas whose working temperature is ≤200℃, as an overpressure protection device.
| Spring inching stainless steel valve main part materials Explanation of materials for main parts | ||||
| NO. | Name of part | A21H-C/A21F KA21Y-C Materials | A21W-P/A21F-P KA21Y-P Materials | A21Y-R Materials |
| 1 | Union | 20 | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti |
| 2 | Union nut | 35 | 2Cr13 | 1Cr18Ni9Ti |
| 3 | Nozzle | 35 | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti |
| 4 | Body | 2Cr13 | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti |
| 5 | Disc | 2Cr13/2Cr13+PTFE | 1Cr18Ni9Ti/1Cr18nI9Ti+PTFE | 1Cr18Ni12Mo2Ti |
| 6 | Spring washer | 2Cr13 | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti |
| 7 | Spring | 50CrVA | 50CrVA Coated Teflon | 50CrVA Coated Teflon |
| 8 | Locking nut | Q235-A | 2Cr13 | 1Cr18Ni9Ti |
| 9 | Spring guide | 2Cr13 | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti |
| 10 | Adjusting nut | Q235-A | 2Cr13 | 1Cr18Ni12Mo2Ti |
| Sealing surface of material | "Y" Co Depositing stellite, "H" D507 Depositing D507, "W" body | |||
| Dimensions (mm) ofspring micro-opening stainless steel safety relief valve | ||||||||||
| Type | (DN) Nominal diameter | do | d | Do | M | d1 | D1 | L | L1 | H |
| KA21Y-16C A21H-16C A21H-40 A21W-16P A21W-40P KA21Y-16P | 15 | 12 | 15 | 20 | M27 1.5 | G1/2" | 30 | 35 | 76 | 66 |
| 20 | 16 | 20 | 25 | M33 1.5 | G3/4" | 34 | 40 | 87 | 68 | |
| 25 | 18 | 25 | 31 | M39 1.5 | G1" | 40 | 50 | 100 | 105 | |
| A21Y-64 A21Y-64P A21Y-100 A21Y-100P | 15 | 10 | 15 | 25 | M39 1.5 | G1" | 44 | 50 | 100 | 66 |
| 20 | 10 | 20 | 31 | M39 1.5 | G1" | 44 | 50 | 100 | 68 | |
| 25 | 12 | 25 | 31 | M39 1.5 | G1" | 44 | 50 | 100 | 105 | |
| A21W-160 /160P | 15 | 8 | 20 | / | M24 2 | G1" | 44 | 50 | 100 | 261 |
| 20 | 8 | 25 | / | M33 2 | G1" | 44 | 50 | 100 | 261 | |
| 25 | 8 | 28 | / | M36 2 | G1" | 44 | 50 | 100 | 285 | |
