# US 7,743,787 B2 · Mud saver valve with magnetic latching > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,743,787 B2 - Document ID: US7743787B2 - Status: Granted - Kind: B2 - Application number: 11/825,557 - Filed: 2007-07-09 - Published: 2009-01-15 - Granted: 2010-06-29 - Earliest claimed: 2007-07-09 - Assignees: Cmv - Inventors: Benton Frederick Baugh - Web page: https://patentgrep.com/patent/US7743787B2 ## CPC - E21B 21/106: {Valve arrangements outside the borehole, e.g. kelly valves (valves specifically for maintaining circulation of drilling fluid while connecting or disconnecting tubular joints E21B21/019)} - Y10T 137/7773: Supporting valve only spring biased - Y10T 137/778: Axes of ports co-axial - Y10T 137/7834: Valve seat or external sleeve moves to open valve - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A mud saver valve for retaining drilling fluid in the Kelly of a rotary drilling rig for insertion into a Kelly sub with an enlarged opening inside having a valve and hollow piston closing the flow in a first position and having flow through when the hollow piston is moved by flow against a spring to an open position compressing a spring to stack height, the spring being magnetized to provide magnetic latching to assist in holding the hollow piston in the open position at flow rates lower than it would otherwise be held open. ## Claims ### Claim 1 A mud saver valve for retaining drilling fluid in the kelly of a rotary drilling rig, comprising: a kelly sub defining an open-ended elongated body having threaded ends for forming a connection between the Kelly and a drill pipe string; an enlarged bore formed in said elongated body; a tubular body received within said enlarged bore of said elongated body; a hollow piston axially disposed within said tubular body, said piston being axially movable relative to said tubular body and defining a fluid passage there through; a valve removably mounted within said tubular body, said valve cooperating with said piston to normally close the fluid passage through said piston, wherein said hollow piston is movable between a first closed and second open position; a stop member removably connected to said tubular body, said stop member including a first internal circumferential tapered shoulder for limiting downward movement of said valve; and a magnetized spring for urging said hollow piston into engagement with said valve, said magnetized spring being responsive to flow in a first direction through said mud saver valve to move said hollow piston from a first closed position to a second open position compressing said magnetized spring to the stack height position of said magnetized spring, said magnetized spring being sufficiently magnetized to cause said magnetized spring to urge said magnetized spring to remain in said stack height position when said flow is reduced and thereby to tend to resist said mud saver valve from moving from said second open position to said first closed position. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein said magnetized spring is manufactured from a square wire. ### Claim 3 (depends on 1) The apparatus of claim 1 wherein said magnetized spring is manufactured from a round wire. ### Claim 4 (depends on 1) The apparatus of claim 1 wherein said magnetized spring is manufactured from a rectangular wire. ### Claim 5 (depends on 1) The apparatus of claim 1 wherein said valve means includes a retrieval profile for engagement by a retrieval tool for removal of said valve means from said tubular body. ### Claim 6 A mud saver valve for retaining drilling fluid in the Kelly of a rotary drilling rig, comprising: a Kelly sub defining an open-ended elongated body having threaded ends for forming a connection between the Kelly and a drill pipe string; an enlarged bore formed in said elongated body; a tubular body received within said enlarged bore of said elongated body; a hollow piston axially disposed within said tubular body, said piston being axially movable relative to said tubular body and defining a fluid passage there through; a valve removably mounted within said tubular body, said valve cooperating with said piston to normally close the fluid passage through said piston, wherein said hollow piston is movable between a first closed and second open position; a stop member removably connected to said tubular body, said stop member including a first internal circumferential tapered shoulder for limiting downward movement of said valve; and a magnetized spring for urging said hollow piston into engagement with said valve, said magnetized spring being responsive to flow in a first direction through said mud saver valve moving said hollow piston from a first closed position to a second open position compressing said magnetized to the stack height of said magnetized wherein adjacent coils are in contact with one another, said magnetized spring being sufficiently magnetized to cause said magnetized spring to urge said magnetized spring to remain in said stack height position when said flow is reduced and thereby to tend to resist said mud saver valve from moving said second open position to said first closed position. ### Claim 7 (depends on 6) The apparatus of claim 6 wherein said magnetized spring is manufactured from a square wire. ### Claim 8 (depends on 6) The apparatus of claim 6 wherein said magnetized spring is manufactured from a round wire. ### Claim 9 (depends on 6) The apparatus of claim 6 wherein said magnetized spring is manufactured from a rectangular wire. ### Claim 10 (depends on 6) The apparatus of claim 6 wherein said valve means includes a retrieval profile for engagement by a retrieval tool for removal of said valve means from said tubular body. ### Claim 11 A mud saver valve for retaining drilling fluid in the Kelly of a rotary drilling rig, comprising: a valve removably mounted within said mud saver valve, a hollow piston being axially movable relative to said mud saver valve from a first closed position engaging said valve and a second open position distal from said valve, a magnetized spring for urging said hollow piston into engagement with said valve, said magnetized spring being responsive to flow in a first direction through said mud saver valve urging said hollow piston from a first closed position to a second open position distal from said valve compressing said magnetized spring to the stack height of said magnetized spring wherein adjacent coils are in contact with one another, and said magnetized spring being sufficiently magnetized to cause said magnetized spring to urge said magnetized spring to remain in said stack height position when said flow is reduced and thereby to tend to resist said mud saver valve from moving said second open position to said first closed position. ### Claim 12 (depends on 11) The apparatus of claim 11 wherein said magnetized spring is manufactured from a square wire. ### Claim 13 (depends on 11) The apparatus of claim 11 wherein said magnetized spring is manufactured from a round wire. ### Claim 14 (depends on 11) The apparatus of claim 11 wherein said magnetized spring is manufactured from a rectangular wire. ### Claim 15 (depends on 11) The apparatus of claim 11 wherein said valve means includes a retrieval profile for engagement by a retrieval tool for removal of said valve means from said tubular body.