Pressure seal gate valves are engineered for high-pressure applications and are prized for their compact construction and straightforward maintenance. Commonly utilized in sectors such as power generation, the pulp and paper industry, and oil refineries, these valves have evolved significantly since their inception in the early 20th century.
Originally, pressure seal valves were devised to alleviate the weighty burden of large vessels and to cope with the elevated pressures characteristic of power plants and various industrial settings. Today, they are predominantly employed in conditions of extreme temperature and pressure, with a standard pressure rating around 900 psi.
Actuation of pressure seal gate valves is typically achieved through hydraulic, electric, or pneumatic systems, with manual operation provided as standard. Industry best practices advocate for hot torquing during installation, which can greatly minimize leakage risks at the body/bonnet joint. However, neglecting to perform this step correctly could result in damage to critical valve components.
Characteristics of Pressure Seal Gate Valves
Designed for demanding high-pressure environments in industries like chemical processing, these valves boast a streamlined, space-saving design and lighter weight, suitable for pressures exceeding 100 bar, though they can accommodate lower pressures as well.
They incorporate a metallic gasket and a segmented thrust ring, which is a distinctive feature ensuring a secure seal.
Capacity and Construction
The valve body is designed with a radial bore that houses a segmental ring, tightened to a specific torque to guarantee the seating surfaces are firmly in place, thus reducing leakage potential. The valve can handle pressures up to 2,500 psi, contingent upon its rating.
Seat rings are commonly manufactured from CoCr-A alloys for a robust seal, while the segmented thrust ring is embedded in a precisely machined annular groove in the body. The bonnet is crafted from forged steel, known for its superior strength due to its fine grain structure.
Compliance and Customization
Adhering to ASME Boiler and Pressure Vessel Codes, these valves are available in diverse configurations, including globe, swing check, and various other types suited for specific processes like catalytic reforming. Motorized options are also available for automated operation, and high-temperature stem expansion compensators can be integrated based on the application's demands.
Applications
Pressure seal gate valves are deployed across a broad spectrum of uses in chemical plants, refineries, pulp and paper mills, and power generation facilities. Their compact and lightweight design is particularly advantageous for high-pressure services. They are frequently the valve of choice for liquid pipelines, especially where the line pressure is significant, such as a minimum of 500 psi.
In summary, pressure seal gate valves provide a durable and dependable solution tailored for high-pressure environments across diverse industries. Their design ensures reliability, efficiency, and compliance with rigorous industry standards, making them essential for critical applications where performance and safety are paramount.
