A21W with welded pipe safety valve
manufacturer: KaiWeiXi Valve group Co., Ltd.
Eml: merry@kaiweixi.com
Tel: +86 (577) 6719 8981
Mob: +86 1815 7711 652（WeChat Same Account）
product drawing
A21W with welded pipe safety valve
Overview
A42Y Spring-Operated Full-Lift Safety Valve is a full-opening safety relief valve sealed with hard alloy. When the system pressure exceeds the preset set pressure, the valve disc quickly lifts to the fully open position, enabling rapid discharge of large flow rates; it automatically closes once the pressure returns to normal. Its "Y"-shaped hard alloy sealing surface possesses extremely high hardness, wear resistance, high temperature resistance, and corrosion resistance, providing reliable overpressure protection specifically for steam, gas, and corrosive medium systems with harsh operating conditions and high durability requirements for the sealing surface. It is primarily installed on power station boiler superheaters, main steam systems, petrochemical high-pressure/high-temperature reactors, synthetic ammonia plants, methanol plants, and various industrial boilers under harsh operating conditions. As a key safety device to prevent system overpressure, it is especially suitable for applications where the medium is high-temperature, corrosive, or has strong erosive properties.
Features:
1. The sealing surface between the hard alloy sealing ("Y"-shaped) valve disc and the valve seat is surfaced with high-hardness alloys such as Stellite, which exhibits excellent wear resistance, high temperature resistance, erosion resistance, and corrosion resistance, ensuring a service life far exceeding that of conventional materials.
2. The spring-loaded full-opening type with large discharge capacity adopts a full-opening structure, featuring a large valve disc opening height, a large discharge area, and strong discharge capacity (displacement). It can quickly reduce system pressure and is suitable for applications such as steam and gas where rapid and large-scale pressure relief is required.
3. The overall structure and material selection for high temperature and high pressure adaptability (such as using heat-resistant alloy steel valve bodies) make it suitable for higher operating temperatures (up to 450°C) and pressures (PN16-PN100), with stable performance.
4. Stable and reliable performance: The spring, after precise calculation and special treatment, exhibits good anti-relaxation performance, ensuring accurate set pressure, small opening and closing pressure difference, and good repeatability.
5. Standard flange connections, such as RF flanges, are commonly used for flange standard connections, which are installed firmly and are easy to integrate into various industrial piping systems.
Dimensions & constructral diagram
A21W with welded pipe safety valveconstructral diagram
Parts List
| NO. | Name of part | A42Y-C A48Y-C KA42Y-C Materials | A42Y-P/KA42Y-P Materials | A42Y-R Materials | DA42Y-P Materials |
|---|---|---|---|---|---|
| 1 | Nozzle | 2Cr13/1Cr18Ni9Ti | ZG1Cr18Ni9Ti | 2G1Cr18Ni12Mo2Ti | ZG1Cr18Ni9Ti |
| 2 | Body | WCB | ZG1Cr18Ni9Ti | 2G1Cr18Ni12Mo2Ti | LCB/ZG1Cr18Ni9Ti |
| 3 | Adjusting ring | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 4 | Disc holder | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 5 | Disc | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 6 | Guide sleeve | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 7 | Bonnet | ZG230-450 | ZG230-450 | ZG230-450 | ZG1Cr18Ni9Ti |
| 8 | Spring | 50CrVA | 50CrVA Coated | 50CrVA Coated | 50CrVA |
| 9 | Stem | 2Cr13 | 1Cr18Ni9Ti/1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti/1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 10 | Adjusting bolt | 45 | 2Cr13 | 2Cr13 | 2Cr13 |
| 11 | Cap | ZG200-400 | ZG200-400 | ZG200-400 | ZG230-450 |
| Sealing surface of material | Depositing stellite | ||||
Performance Specification Sheet
| 公称压力 Normal Pressure | PN | 150 | 300 | 600 | 900 | 1500 | |
|---|---|---|---|---|---|---|---|
| 整体强度 Body strength |
Ps(MPa) | 3.0 | 7.5 | 15 | 22.5 | 38 | |
| Set pressure Pk(MPa) |
0.1-2 | 1.6-5 | 3.2-10 | 8-15 | 10-25 | ||
| 密封压力 Seal pressure |
Pm(MPa) | 90% Pk | |||||
| 回座压力 Reseation pressure |
Ph(MPa) | ≥90% Pk | |||||
| 排放压力 Relieving pressure |
Pp(MPa) | ≤1.1 Pk | |||||
| 开启高度 Lift |
H(mm) | ≥1/4 d0 | |||||
| 适用温度 Appropriate temperature | C | ≤300°C | |||||
| P、R | ≤200°C | ||||||
| 适用介质 Appropriate medium | Air,oil,steam,Water,Corrosive medium | ||||||
Outline dimension table
| Nominal diameter DN(mm) | Dimensions (mm) | |||
|---|---|---|---|---|
| D0 | L | L1 | DN' | |
| 25 | 15 | 110 | 95 | 32 |
| 32 | 20 | 115 | 100 | 40 |
| 40 | 25 | 120 | 110 | 50 |
| 50 | 32 | 165 | 120 | 65 |
| 65 | 40 | 160 | 135 | 80 |
| 80 | 50 | 170 | 135 | 100 |
| 100 | 65 | 195 | 175 | 125 |
| 125 | 80 | 210 | 190 | 150 |
| 150 | 100 | 255 | 230 | 175 |
| 200 | 125 | 300 | 260 | 250 |
| 250 | 150 | 350 | 320 | 300 |
| 300 | 200 | 380 | 350 | 400 |
| 350 | 300 | 500 | 450 | 500 |
| 400 | 350 | 500 | 450 | 500 |
