Howard R Mashaw

52112411, May 18, 1993

Dec 31, 1991

7/815236

Howard R. Mashaw - Carrollton TX
Christopher A. Dines - Dallas TX
Robert C. Hammett - Garland TX
Clark E. Robison - Plano TX

Otis Engineering Corporation - Dallas TX

E21B 3414

166332

A sliding sleeve valve useful in a flow conduit to control and vary area of openings open for flow through the valve. The valve has a sleeve having a through flow passage and the sleeve is moveable between open, intermediate and closed positions. When the sleeve is in open position, the area open for flow through the valve is equal to area through the sleeve flow passage. As the sleeve is moved from open position to intermediate positions toward closed position, the area open for flow at each position is reduced to no area open for flow at closed position and conversely. Also disclosed is a pressure operated shifting tool which when lowered into the sleeve valve selectively locates in the valve, engages the sleeve, moves the sleeve upwardly or downwardly between positions and automatically disengages from the sleeve for retrieval. The invertible shifting module in the shifting tool is provided with a positioning sleeve which determines the distance the sleeve is moved when the shifting tool is operated. The shifting tool also includes structure for disengaging the sleeve valve if the shifting tool cannot move the sleeve or does not automatically disengage after operation and an emergency disconnect which may be operated to disconnect the flow conduit used to lower the shifting tool.

44484275, May 15, 1984

Jun 10, 1983

6/503173

Howard R. Mashaw - The Colony TX

Otis Engineering Corporation - Dallas TX

F16J 1540
E21B 2300

277 73

A valve having a lead seal for controlling flow through a port in the housing of the valve in which the seal is moved from an out of the way position into a position preventing flow through the port. The seal is metallic and by using a piston-type seal expander in combination with a ball catcher pressure exerted within the valve on a ball may be exerted over the entire area defined by the piston to set the seal under very high pressures, after which the ball and its catching tube may be released from the piston and removed from the valve.

49151754, Apr 10, 1990

Feb 21, 1989

7/313598

Howard R. Mashaw - Carrollton TX

Otis Engineering Corporation - Dallas TX

E21B 3414

166332

A sliding sleeve valve well flow control device having a tubular nipple connectable in a well tubing string and side ports for flow into the nipple and a retrievable pack-off sleeve insertable into the nipple for closing the side ports, the sleeve including an equalizing port and J-slots for coacting with a guide lug in the nipple to position the sleeve at an equalizing position prior to retrieving the sleeve from the nipple to minimize the damage to seals around the retrievable sleeve.

49443453, Jul 31, 1990

Mar 9, 1989

7/320965

Howard R. Mashaw - Carrollton TX

Otis Engineering Corporation - Dallas TX

E21B 2302

166206

A lock mandrel for selectively locking a well tool at a desired landing nipple in a well bore, and a running tool for installing the lock mandrel. The lock mandrel includes an upwardly operable expander sleeve for locking the mandrel responsive to an upward force and a selector key assembly for landing the lock mandrel at a landing nipple having a selector profile compatible with the profile on the selector keys of the lock mandrel. The running tool includes a latch key assembly for coupling the running tool with the lock mandrel and an operator lug assembly for operating the lock mandrel. The running tool also includes a non-load bearing shear pin for holding the running tool in a running mode and a emergency release apparatus for releasing the lock mandrel in the well bore and retrieving the lock mandrel with the running tool in the event that the locking mechanism of the lock mandrel is not fully operable in the well bore.