Parallel slide gate valve

Parallel gate valves are widely used in high pressure and high temperature applications such as steam and feed water. Double discs in parallel position with compressed spring between them, double sealing with line pressure provides better sealing performance

Parallel Slide Gate Valve is a special design of a valve
It is an alternative to the traditional flexible wedge-shaped valves. The disc consists of two halves, compressed by a spring, which sit on parallel seat rings. The disc "slides" in contact with the seats, hence the name.

The discs are in permanent contact with the seat rings and get a tight seal thanks to the horizontal spring located between them and without the help of the wedge system.

Sealing mechanism of parallel slide gate valve
When the pipe pressure or pressure difference of two sides is small, the compressed spring will push the discs to the sealing rings, it is the first seal of parallel gate valves under low pressure conditions.

When the pipeline pressure increases, the increasing line pressure will push the disc against the seat ring with force in the low pressure side, which creates the secondary seal. The higher the medium pressure, the better the sealing performance.

Therefore, this type of valve is widely used in high pressure and high temperature services such as steam and feed water.

The advantages of the parallel gate valve over the traditional gate valve type are:

The discs of the parallel gate valve will never seize up in the closed position, while this can happen with a gate valve type that is closed when the pipe is at temperature and open when the pipe is cold.

The opening/closing torque of the parallel gate valve is much lower than with a similar gate valve type, resulting in a smaller actuator and cheaper actuator systems.

The "slide" function keeps dirt away from the sealing surfaces.

The parallel gate valve is widely used in chemical, petroleum, natural gas, oil and in transportation and storage pipelines, with high operating temperatures), and pipelines with suspended particles, urban gas pipelines and hydraulic engineering.