Pressure seal Globe valve

Mô tả

DESIGN

Pressure seal valves are intended for high-pressure and high-temperature applications in all types of fluid, except where severe coking may occur.

A selection of designs and materials would give an excellent service in nuclear steam generating stations, industrial/chemical plants, and thermal power plants.

The pressure seal valve provides the most efficient use for flow passage and sealing, and results in significant weight saving and ease and simple installation and maintenance. Manufacturing and quality assurance procedures include extra controls of dimensional and non-destructive examinations and tests on critical areas such as gasket sealing, weld ends, or stelite sealing surfaces.

CONSTRUCTION

BODY AND BONNET
BODY: Flow areas are designed for minimum turbulence and pressure drop.
BONNET: Ample stuffing box and stellite back seat are to guide accurately stem and back seat.

When designing a PK valve, casting of body and bonnet shall be considered thoroughly as a quality requirement.

SERVICE RECOMMENDATION

The globe valve is normally installed with flow direction and pressure under the disc. In case the flow in valve directs to the opposite direction, always check at factory before installing the valve. Under a certain service condition, especially when a valve is equipped with cylinders or electric motor actuators, there is a cost advantage in designing and installing the valve flow over the disc. If the actuator is sized to such condition, care must be taken to install the valve correctly.
The globe valve is suitable for most throttling applications; however, it must not be used for a prolonged throttling at 10% open or less, which may cause excessive vibration, noise or damage to disc and seat. Use of small valve with a lower flow capacity may permit the valve to be opened to a greater percentage, and thus avoid damage. For continuous severe throttling, a control valve is required.

END CONNECTION