化工阀门的“腐蚀”噩梦？这套全塑/衬塑防腐方案请收好

化工、环保和水处理中的强酸、强碱及腐蚀性介质，会使选型不当的阀门内漏、外漏，甚至释放有害介质。山东龙飞提供从全塑到衬塑的阀门系列，通过隔离介质与金属减少腐蚀。

全塑与衬塑结构

A型酸阀采用PVDF、UPVC、RPP、PTFE等塑料阀体，应对酸碱介质。B型酸阀采用内置式法兰和PVC/PTFE整体镶嵌，结合金属强度与耐腐蚀性能。

衬塑单座调节阀以金属阀体承压，PTFE内衬保护接液面；内壁锚固孔加强结合，PTFE波纹管与内件提供密封，泄漏等级IV。

含杂质及粘稠介质

气动隔膜阀采用无填料结构，避免填料老化外漏。流线型通道和扩大的出口提高通过能力，适应含悬浮颗粒或粘稠污水。

衬塑蝶阀的阀杆与蝶板由PTFE或PFA包覆，抵抗介质与大气腐蚀；唇齿型自密封结构提高密封强度，省去压盖法兰以便执行器直接连接。

材料与排放控制

从PVDF/UPVC全塑到PTFE/PFA衬塑，按配置覆盖原文所述−30°C至150°C工况。波纹管与填料组合密封用于降低挥发性有机物外泄。合适的厂家、材料和结构共同构成防腐方案。

In chemical, environmental and water-treatment applications, strong acids, strong alkalis and other corrosive media can be a greater challenge than pressure alone. Incorrect selection can lead to internal or external leakage and the release of hazardous media. Conventional metal valves may be unsuitable for duties involving hydrochloric, sulfuric or hydrofluoric acid.

Shandong Longfei provides all-plastic and lined valve options to isolate process media from vulnerable metal surfaces.

1. All-plastic and lined construction

Acid valves: types A and B

Two approaches are offered for different acidic-media duties.

Type A: bodies made from materials such as PVDF, UPVC, RPP or PTFE provide an all-plastic wetted structure for corrosive acids and alkalis.
Type B: an internal flange arrangement and integrated PVC/PTFE insert combine a mechanically strong body with corrosion resistance.

Lined single-seat control valve

A metal body provides strength while a PTFE lining protects the wetted surfaces. Cast anchoring recesses inside the body improve the lining’s attachment. PTFE bellows and PTFE trim provide sealing, with the article specifying leakage Class IV.

2. Designs for contaminated or viscous media

Pneumatic diaphragm valve

Packing-free construction avoids external leakage associated with aging conventional packing. A streamlined passage and enlarged outlet area improve the handling of suspended particles and viscous wastewater.

Lined butterfly valve

The stem and disc are fully enclosed in PTFE or PFA lining to resist process and atmospheric corrosion. The self-sealing lip arrangement provides sealing strength, while eliminating a separate gland flange allows direct actuator connection and a more compact assembly.

3. Materials and emissions control

The range spans all-plastic PVDF/UPVC and PTFE/PFA-lined construction, covering the article’s stated −30°C to 150°C corrosion-service range according to the selected configuration.

Combined bellows and packing seals are intended to control fugitive emissions in chemical applications with demanding VOC requirements.

Selection matters

Corrosion protection starts with matching the valve and its materials to the medium. Shandong Longfei’s lined and all-plastic technologies provide options for building an appropriate corrosion barrier into the process.