A buried extended stem welded ball valve is a valve unit designed for direct burial underground installation by extending the valve stem structure. Its main features include a fully welded body, an extended stem design, and a leak-proof sealing system, suitable for low-temperature, high-pressure, and corrosive medium applications.

Structural characteristics

The valve body is constructed with a full-welded design, eliminating the risk of external leakage. The valve body is made of the same material as the pipeline (such as carbon steel or stainless steel), ensuring seismic resistance and long-term reliability. The valve stem length is customizable (e.g., 50cm to 2 meters) and equipped with anti-loosening devices (such as a cap cavity with a multi-bolt fastening system) to prevent stem displacement during transportation or vibration.

Sealed design

Sealed components are made of carbon-fiber reinforced PTFE (PTFE+C) material, ensuring both room temperature and low-temperature sealing properties. The valve stem bottom is equipped with a full-perfluoroelastomer sealing ring and a PTFE self-sealing gasket, offering a dual protection structure to effectively prevent medium leakage.

Applicable Scenarios

‌Low-Temperature Medium: Liquid Nitrogen, Liquefied Natural Gas (-196℃ to +80℃)‌

Energy Pipelines: Urban Gas, Petrochemical, Heating Network (-29℃~200℃)

Industrial Equipment: Coal, rubber, papermaking, etc., pipeline systems

Operation Method

Supports various operation methods including handles, gears (vertical/horizontal), and electric, simplifying underground space operation procedures. Warranty period typically 20 years, compliant with ASME/API/GB and other international standards.