Control ports for gate valve structure

Claim 2

A gate valve structure comprising a main valve body having a flowline therethrough and a cavity therein intersecting the flowline and opening to a side of the body, a downstream seating assembly on one side of the cavity adjacent the outlet side of the flowline and an upstream seating assembly on an opposed side of the cavity adjacent the inlet side of the flowline, and a gate mounted on said body for movement within the cavity to open and close the flowline, said gate having a main bore therethrough adapted to align with the flowline in the open position thereof and at least one relatively small diameter bore adjacent the main bore, said small diameter bore having a longitudinal axis inclined outwardly from the upstream side of the gate and having an inclination at least of a magnitude to permit the downstream end of the small diameter bore to clear the downstream seating assembly before the upstream end of the small diameter bore is in fluid communication with and exposed to the interior of the flowline whereby fluid pressure from the upstream side of the flowline is directed by the small diameter inclined bore away from the downstream seating assembly.

Claim 3

A gate valve structure as set forth in claim 1 wherein a plurality of small diameter bores are arranged on the side of the main bore adjacent the flowline when the gate is in a closed position.

Claim 4

A gate valve structure as set forth in claim 1 wherein said main bore is positioned in the lower portion of the gate and said small diameter bore is positioned adjacent the upper side of the main bore.

Claim 5

A gate valve structure as set forth in claim 2 wherein said main bore is positioned in the upper portion of the gate and said small diameter bore is positioned adjacent the lower portion of the main bore.

Claim 6

A gate valve structure comprising a main valve body having a flowline therethrough and a cavity therein intersecting the flowline and opening to a side of the body, a downstream seating assembly on one side of the cavity adjacent the outlet side of the flowline and an upstream seating assembly on an opposed side of the cavity adjacent the inlet side of the flowline, and a gate mounted on said body for movement within the cavity to open and close the flowline, said seating assemblies each having a central opening therethrough in alighment with the flowline and carrying a sealing element to contact the gate in sealing relation therewith, said gate having a main bore therethrough adapted to align with the flowline in the open position thereof and a plurality of relatively small diameter bores positioned between the main bore and the flowline when the gate is in a closed position, said small diameter bores having longitudinal axes inclined outwardly from the upstream side of the gate and having an inclination at least of a magnitude to permit the downstream ends of the small diameter bores to clear the downstream seating assembly before the upstream ends of the small diameter bores are in fluid communication with and exposed to the interior of the flowline whereby fluid pressure from the upstream side of the flowline is directed by the small diameter inclined bores away from the downstream seating assembly.

Claim 7

A gate valve structure comprising a main valve body having a flowline therethrough and a cavity therein intersecting the flowline and opening to a side of the body, a downstream seating assembly on one side of the cavity adjacent the outlet side of the flowline and an upstream seating assembly on an opposed side of the cavity adjacent the inlet side of the flowline, and a gate mounted on said body for movement within the cavity to open and close the flowline, said seating assemblies each having a central opening therethrough in alighment with the flowline and carrying a sealing element to contact the gate in sealing relation therewith, said gate having a main bore therethrough adapted to align with the flowline in the open position thereof and a plurality of relatively small diameter bores positioned between the main bore and the flowline when the gate is in a closed position, said small diameter bores having longitudinal axes inclined outwardly from the upstream side of the gate and having an inclination at least of a magnitude to permit the downstream ends of the small diameter bores to clear the downstream seating assembly before the upstream ends of the small diameter bores are in fluid communication with and exposed to the interior of the flowline whereby fluid pressure from the upstream side of the flowline is directed by the small diameter inclined bores away from the downstream seating assembly.

Claim 8

A gate valve sTructure as set forth in claim 5 wherein said plurality of relatively small diameter bores are positioned at progressively increasing distances from the main bore.

Claim 9

A gate valve structure as set forth in claim 6 wherein said small diameter bores are positioned in laterally staggered relation to each other, and said small diameter bores closest to said main bore are exposed to fluid pressure within the inlet flowline slightly before the initial opening of the main bore. gate

Claim 10

A gate valve structure comprising a main valve body having a flowline therethrough and a cavity therein intersecting the flowline and opening to a side of the body, a downstream seating assembly on one side of the cavity adjacent the outlet side of the flowline and an upstream seating assembly on an opposed side of the cavity adjacent the inlet side of the flowline, and a gte mounted on said body for movement within the cavity to open and close the flowline, said gate having a main bore therethrough adapted to align with the flowline in the open position thereof, said main bore having a longitudinal axis inclined outwardly from the upstream side of the gate, the leading edge portion defining the bore upon movement of the gate toward an open position being tapered outwardly from the upstream side of the gate and clearing the downstream seat before a corresponding edge portion on the upstream side of the gate clears the upstream seat.

Claim 11

A gate valve structure comprising a main valve body having a flowline therethrough and a cavity therein intersecting the flowline and opening to a side of the body, a downstream seating assembly on one side of the cavity adjacent the outlet side of the flowline and an upstream seating assembly on an opposed side of the cavity adjacent the inlet side of the flowline, and a gte mounted on said body for movement within the cavity to open and close the flowline, said gate having a main bore therethrough adapted to align with the flowline in the open position thereof, said main bore having a longitudinal axis inclined outwardly from the upstream side of the gate, the leading edge portion defining the bore upon movement of the gate toward an open position being tapered outwardly from the upstream side of the gate and clearing the downstream seat before a corresponding edge portion on the upstream side of the gate clears the upstream seat.

Claim 12

A gate valve structure as set forth in claim 8 wherein a plurality of small diameter bores are arranged on the side of the main bore adjacent the flowline when the gate is in a closed position.