Long life gate valve

• US 4,449,547 A
• Filed: 02/01/1983
• Issued: 05/22/1984
• Est. Priority Date: 11/26/1980
• Status: Expired due to Fees

• Current Assignee: Rafael Krakovsky
• Original Assignee: Rafael Krakovsky
• Inventors: Krakovsky, Rafael
• Primary Examiner(s): Walton, George L.
• Application Number:
  US06/462,988
• Time in Patent Office: 476 Days
• Field of Search: 137/330, 137/331, 137/625.3, 137/625.31, 137/628, 251/176, 251/193, 251/195, 251/205, 251/210, 251/267, 251/270, 251/298, 251/299, 251/300, 251/301, 251/326, 251/327, 251/328, 138/45, 138/46
• US Class Current: 137/330
• CPC Class Codes: F16K 29/00 Arrangements for movement of valve members other than for opening and closing the valve, e.g. for grinding-in, for preventing sticking
• CPC Class Codes: F16K 3/06 in the form of closure plates arranged between supply and discharge passages F16K3/10 takes precedence
• CPC Class Codes: Y10T 137/6198 Non-valving motion of the valve or valve seat

Abstract

A gate valve presents on a flat valve seat surface defining a fluid flow path the mating flat surface of a freely rotatable circular disc carried at its center along a longitudinally moving straight line axis. The valve seat defines a fluid flow aperture asymmetrically disposed to the disc center movement line to thereby create a turning moment from pressure and flow of fluid through the valve seat. This serves without ratching mechanisms to rotate the disc periphery randomly thereby presenting different disc edge portions in a wear position from the fluid flow. Accordingly, wear is evenly distributed about the peripheral edge to significantly increase life and reduce sealing problems from chemical or sediment materials coming between the disc and valve seat surfaces. By mounting the disc and valve seat surfaces at an acute angle to the axis of movement, the disc is freely rotatable and subject to the turning moment up until the time they are frictionally wedged together in a sealed valve closure position.

Claims

1. In a long life gate valve having a pair of rotatable closure discs mounted for longitudinally positioning into partial or full registration with mating valve seats to control fluid flow, the improvement for extending valve life by distributing wear about the periphery of the disc resulting from fluid flow thereacross substantially about the entire disc periphery for even wear thereabout, comprising in combination,

means presenting two spaced valve seats with flat surfaces surrounding flow apertures of different size that define a fluid flow path through the valve from a larger upstream aperture to a smaller downstream aperture,

a mating circular closure disc having a flat surface for mating with each said valve seat surface in a registration position for fully closing said fluid flow path,

movement means for longitudinally moving the center of both circular disc surfaces in unison along a straight line axis into and out of seated registration on said seat surfaces to restrict and close the fluid flow path,

means for holding at least the downstream closure disc in a freely rotatable mode about its center as it is moved along said axis into and out of seated registration so that it is rotatable by fluid flow in unseated transit positions,

and aperture structure defined by said valve seats to present a fluid flow path asymmetrically disposed about the rotatable downstream disc whereby the fluid flow and pressure through the aperture structure and fluid flow path imparts a turning moment to the freely rotatable disc thereby to randomly present different portions of the disc edge to the fluid flow path through the valve seat in response to said turning moment when the discs are longitudinally moved in and out of registration

2. The improved combination defined in claim 1 further wherein said pair of discs are carried by said movement means with their flat surfaces disposed at an acute angle, and the mating valve seat surfaces for both discs are disposed to receive the discs in wedged position therebetween to close the flow path through the valve seats.

3. The valve defined in claim 1 further comprising a downstream aperture shape that limits the flow wear on the edge of the downstream mating disc to a confined peripheral arc area.