编者按
上一期介绍循环水、蒸汽的流道与导向，本期关注氯气处理中材料腐蚀、波纹管疲劳和调节精度问题。
工况要求
阀门需在指定氯气条件下抵抗腐蚀，避免点蚀、开裂；频繁动作及压力波动可能引起波纹管应力集中、疲劳破裂；流量波动又会影响下游效率与安全。因此需要按工况配置金属波纹管密封调节阀。
技术方案
哈氏合金C276
本文专用方案的阀体、阀芯和关键内件采用Hastelloy C276，以抵抗介质并保持长期结构完整性。
顶部六角导向
导向结构分散启闭应力，减少局部应力集中与疲劳断裂，改善频繁调节的可靠性。
精密制造
大变形量、长寿命焊接波纹管配合精密加工装配，原文给出的控制精度目标为2%以内。
应用报告
原文列举山东金岭化学、昌邑海能化学，报告在氯气工段降低阀门泄漏引起的停机风险，并减少维护。
随文产品页
通用EGSC气动薄膜波纹管单座调节阀采用多弹簧执行机构、波纹管与填料组合密封，适用于需限制外漏的介质。口径¾–8英寸，ANSI Class 150/300及1.6、4.0、5.0 MPa，温度−29°C至350°C，泄漏IV，线性或等百分比，法兰FF/RF/RJ，金属齿形垫，顶部导向。材料栏引用另表，而本文专用氯气配置明确为C276。
结语与下期
继续深化材料及结构研究，以可靠产品服务氯碱安全生产。下一期转向盐水、湿氯气和盐酸等条件下衬层渗透、鼓包和脱落问题，介绍PTFE衬塑系列。
产品规格表
| 参数 | 原文规格 |
|---|
| 型号 | EGSC |
| 试验标准 | GB/T 4213-2024, effective July 1, 2025 |
| 口径 | ¾–8 inches |
| 压力等级 | ANSI Class 150/300; 1.6, 4.0 or 5.0 MPa |
| 温度范围 | −29°C to 350°C |
| 泄漏等级 | IV |
| 阀体与内件材料 | The sheet refers to a separate material table; the article’s dedicated chlorine configuration specifies C276 |
| 流量特性 | 线性或等百分比 |
| 连接 | Flanged: FF, RF or RJ |
| 垫片 | 金属齿形垫 |
| 导向 | 顶部导向 |
| 附件 | Positioner, filter regulator, solenoid valve |
Editor’s introduction
The first article examined Yilong’s flow-path and top-guided construction for circulating water and steam. The second addresses chlorine handling, where corrosion, bellows fatigue and accurate control require particular attention.
1. Demanding requirements in dry-chlorine service
The article identifies three concerns:
- Material resistance: the valve must withstand the specified chlorine-service conditions without pitting, cracking or loss of structural integrity.
- Bellows fatigue: repeated movement and pressure fluctuations can concentrate stress in an inadequately guided bellows. A fracture can release hazardous chlorine.
- Control stability: flow variations can affect the performance and safety of subsequent process stages.
Yilong’s proposed solution is a metal-bellows-sealed control valve configured for this duty.
2. Materials and structural design
Hastelloy C276
For the dedicated configuration described in this article, the body, plug and critical internal components use Hastelloy C276. The material is selected to resist the process medium and retain structural integrity during extended operation.
Top hexagonal guidance
Bellows life depends on how it is loaded. A top hexagonal guide distributes stresses during movement and limits local stress concentrations that can cause fatigue fracture. The aim is stable, reliable operation during frequent modulation.
Manufacturing and control accuracy
A welded bellows designed for substantial movement and long life is combined with precise machining and assembly. The article states a control-accuracy target within 2% to meet the flow-regulation requirements of chlorine handling.
3. Reported applications
The source cites Shandong Jinling Chemical Co., Ltd. and Changyi Haineng Chemical Co., Ltd. as users. It reports reduced risks of unplanned shutdown from valve leakage and less frequent maintenance in their chlorine-handling sections.
4. Bellows-sealed single-seat valve product sheet
The general product sheet included with the article describes a multi-spring diaphragm actuator and a single-seat bellows valve. Combined bellows and packing sealing is intended for flammable, explosive, toxic or volatile media in chemical, power, metallurgical and new-material applications.
| Parameter | Published specification |
|---|
| Model | EGSC |
| Test standard | GB/T 4213-2024, effective July 1, 2025 |
| Nominal size | ¾–8 inches |
| Pressure rating | ANSI Class 150/300; 1.6, 4.0 or 5.0 MPa |
| Temperature range | −29°C to 350°C |
| Leakage class | IV |
| Body and trim materials | The sheet refers to a separate material table; the article’s dedicated chlorine configuration specifies C276 |
| Flow characteristic | Linear or equal percentage |
| Connections | Flanged: FF, RF or RJ |
| Gasket | Serrated metal gasket |
| Guidance | Top guided |
| Accessories | Positioner, filter regulator, solenoid valve |
5. Safety and further development
Yilong’s engineering team emphasizes application knowledge, material selection and mechanical design. Continued work on materials and construction is intended to improve reliability in demanding chlor-alkali service.
Next in the series
Brine, wet chlorine and hydrochloric-acid duties introduce another problem: permeation that can blister or detach a lining. The final article examines the PTFE-lined product family and its coverage of strongly corrosive liquid applications.
