Your location:



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.

A42Y Spring-Operated Full-Lift Safety Valve Product Diagram
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.

A42Y Spring-Operated Full-Lift Safety Valve Structural Diagram
Part Name Material
| NO. | 零件名称 Name of part | A42Y-C A48Y-C KA42Y-C 材料 Materials | A42Y-P/K A42Y-P 材料 Materials | A42Y-R 材料 Materials | DA42Y-P 材料 Materials |
| 1 | 阀座 Nozzle | 2Cr13/1Cr18Ni9Ti | ZG1Cr18Ni9Ti | 2G1Cr18Ni12Mo2Ti | ZG1Cr18Ni9Ti |
| 2 | 阀体 Body | WCB | ZG1Cr18Ni9Ti | 2G1Cr18Ni12Mo2Ti | LCB/ ZG1Cr18Ni9Ti |
| 3 | 调节圈 Adjusting ring | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 4 | 反冲盘 Disc holder | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 5 | 阀瓣 Disc | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 6 | 导向套 Guide sleeve | 2Cr13/1Cr18Ni9Ti | 1Cr18Ni9Ti | 1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 7 | 阀盖 Bonnet | ZG230-450 | ZG230-450 | ZG230-450 | ZG1Cr18Ni9Ti |
| 8 | 弹簧Spring | 50CrVA | 50CrVA包覆氟塑料 Coated Teflon | 50CrVA包覆氟塑料 Coated Teflon | 50CrVA |
| 9 | 阀杆Stem | 2Cr13 | 1Cr18Ni9Ti/1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti/1Cr18Ni12Mo2Ti | 1Cr18Ni9Ti |
| 10 | 调整螺杆Adjusting bolt | 45 | 2Cr13 | 2Cr13 | 2Cr13 |
| 11 | 阀帽Cap | ZG200-400 | ZG200-400 | ZG200-400 | ZG230-450 |
| 密封面材料 Sealing surface of material | 堆焊Co基硬质合金 Depositing stellite | ||||
Performance Specifications Table
| 公称压力 Normal Pressure | PN | 150 | 300 | 600 | 900 | 1500 |
| 壳体强度 Body strength | Ps(MPa) | 3.0 | 7.5 | 15 | 22.5 | 38 |
| 整定压力 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℃ | ||||
| P、R | ≤200℃ | |||||
| 适用介质 Appropriate medium | 空气、水、油品、蒸气、腐蚀性介质 Air,oil,Steam,Water,Corrosive medium | |||||

A42Y Spring-Operated Full-Lift Safety Valve Outline Drawing
Dimension Chart
| 公称通径 Nominal diameter DN(mm) | 尺寸 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 |

Model:
A44Y-10C/A44Y-16C/A44Y-25C/A44Y-40C/A44Y-64C/A44Y-100C/A44Y-10C/A44Y-16P/A44Y-25P/A44Y-40P/A44Y-64P/A44Y-100P/A44Y-10C/A44Y-16R/A44Y-25R/A44Y-40R/A44Y-64R/A44Y-100RSpecification:
DN25-DN400Pressure:
10PN-100PNMaterial:
cast steel, stainless steel, bi-directional stainless steel
Model:
A21H-16C / A21H-25C / A21H-40C / A21H-16P / A21H-25P / A21H-40PSpecification:
DN15-DN25Pressure:
16PN-40PNMaterial:
cast steel, stainless steel, copper
Model:
A40Y-10C/A40Y-16C/A40Y-25C/A40Y-40C/A40Y-64C/A40Y-100C/A40Y-10C/A40Y-16P/A40Y-25P/A40Y-40P/A40Y-64P/A40Y-100P/A40Y-10C/A40Y-16R/A40Y-25R/A40Y-40R/A40Y-64R/A40Y-100RSpecification:
DN50-DN150Pressure:
10PN-100PNMaterial:
cast steel, stainless steel, bi-directional stainless steel