Walker Colin: Drilling apparatus.. Pilot Drilling Control, October 4, 1989: EP0335543-A1 (20 worldwide citation)

Drilling apparatus comprises a hollow drill pipe (2) extending through a drill hole (4) to a mud motor (8). The motor (8) drives a compressor (12) through a shaft (14). An annular passageway (16) around the compressor (12) leads to a drill bit (18) having nozzles (20) providing an outlet from the pa ...

Swietlik George, Abbott Malcolm Adrian: Directional drilling apparatus incorporating indexing, fluid operated, spring biassed activation means. Pilot Drilling Control, April 26, 2000: GB2342935-A (13 worldwide citation)

An indexing mechanism 134 allows distanced control of a drill bit in a submarine or subterranean drilling exercise. The drilling mud is feed to the drill bit under pressure. The indexing mechanism is arranged within the main housing so that a main restoring means 146 (spring) is dominating the force ...

George Swietlik, Joseph Fitzgerald: Downhole fluid-tight flexible joint. Pilot Drilling Control, Seyfarth Shaw, May 15, 2007: US07216726 (10 worldwide citation)

A downhole tool comprises a joint, and a resilient member 65 which extends through the joint and provides a restoring force which tends to strengthen the joint. The joint may comprise a flex coupling 61 which allows limited articulation of the joint. First and second drill string sections 63, 64 may ...

Swietlik George, Large Robert: Apparatus for connecting a drill string tubular to a top drive. Pilot Drilling Control, August 15, 2007: GB2435059-A (10 worldwide citation)

An apparatus which may be used to connect a portion of a drill string to a top drive includes a connector 10 which provides a fluid tight connection between a fluid supply and a drill string (4, fig 1). The connector includes a piston rod 20 and a cylinder 15, the piston rod 20 having a seal 130 at ...

George Swietlik, Robert Large: Drill-string connector. Pilot Drilling Control, Osha • Liang, April 6, 2010: US07690422 (9 worldwide citation)

A connector (10) which provides a fluid tight connection between a fluid supply and a drill-string (4), the connector (10) comprising a piston-rod (20) and a cylinder (15), the piston-rod (20) having a seal at or towards its free end which is adapted to sealingly engage the drill-string (4) when the ...

George Swietlik, Christopher David Down: Downhole drilling tool. Pilot Drilling Control, Seyfarth Shaw, May 27, 2008: US07377337 (9 worldwide citation)

A downhole drilling tool 136 comprises a drillstring 138, a drilling head 140, and a freewheel 144 for transferring drive from the drillstring to the drilling head. The freewheel 144 is positioned between the drillstring 138 and the drilling head 140.


Swietlik George, Large Robert: Flow stop valve controlled by pressure difference. Pilot Drilling Control, August 19, 2009: GB2457497-A (6 worldwide citation)

A flow stop valve (20) is positioned in a downhole tubular (Fig.1c, 6), wherein: (A) the flow stop valve 20 is in a closed position when a pressure difference between fluid outside the downhole tubular (6) and inside the downhole tubular (6) at the flow stop valve 20 is below a threshold value, ther ...

Swietlik George, Abbott Malcolm Adrian: Mecanisme dindexage et appareil incorporant ce mecanisme, Indexing mechanism and apparatus incorporating the same. Pilot Drilling Control, Pilot Drilling Control, SIM & MCBURNEY, December 13, 2005: CA2285767 (5 worldwide citation)

Within a longitudinally-extending main housing having a longitudinally-extending duct, an indexing mechanism comprises a mandrel within the duct and capable of longitudinal movement relative to the main housing; a cam sleeve rotatable with respect to the mandrel but constrained in terms of longitudi ...

Swietlik George: Downhole telemetry system. Pilot Drilling Control, November 8, 1995: GB2289117-A (4 worldwide citation)

In well drilling, a downhole telemetry system, employing pressure pulsing of mud flow down a drillstring, comprises a valve having a pattern of orifices which variably chokes mudflow to cause dependent variations in back-pressure at the surface. The pattern of orifices is preferably formed by one or ...