Ported slide gate valve with gate motion to break scale build up

#The present invention relates to valves in general and more particularly, to a ported gate valve for use in slurry service.

#Ported slide gate valves are usually used in slurry service because these valves provide good wear resistance to abrasive slurries. Ported slide gate valves with rubber or elastomeric seats that allow tight shut-off provide the most efficient type of valve performance in these harsh environments. The rubber or elastomeric seats also serve as wear resistant liners for the valve interiors. Such a valve conventionally utilizes a gate with an aperture and an operator that opens or closes the gate in one motion.

#Some slurry systems generate a hard scale in the pipelines and valve interior surfaces. In those environments, operators are typically configured with larger than normal operating forces so that the opening or closing of the gate breaks the hard scale build up.

#FIG. 1 is a perspective view of a valve according to the invention in an open position, partially in cross-section to show operation;

#FIG. 2 depicts the valve of FIG. 1 in a closed position, according to the invention;

#FIG. 3 depicts the valve in an intermediate position, according to the operation of the invention;

#FIG. 1, shows a typical ported slide gate valve 10. The valve 10 is shown in an open position. The valve 10 has a gate 15, which is a planar member having an aperture 16 located in its surface. On each side of the valve are ported pipe-coupling elements 21 and 22. Each pipe-coupling element has a seat located therein. The seats are typically made of a rubber or elastomeric material, as described above. They are designated on one side by the numeral 23. On the other side, it is shown, along with the associated pipe-coupling element 22, in cross section and designated by the numeral 24.

#The gate 15 is connected to a piston rod 31, which in operation moves the gate upwards and downwards. The piston rod is surrounded by a bellows 61, which is typically constructed of a Hyperlon or nylon material and is used to prevent external contamination from damaging the piston rod 31.

#The piston rod is secured to a piston head 32. This piston rod and associated head comprise a primary piston 33. Located near the primary piston 33 is a secondary piston 43, comprising another piston rod 41 and head 42. The primary piston head 32 is configured to move within a first cylinder 35. The secondary piston head 42 is configured to move within a second cylinder 45, and its associated rod 41 is movably placed within an aperture 48 in an intermediate member 55.