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Table T8. Hammer drill drilling test data, Hole 1104E.

Time
(UTC)

Flow rate
(gpm)

Pressure
(psi)

Weight
on bit
(lb)

Rotary
speed
(rpm)

Torque
(ft-lb)

Notes

0140

100

160

10,000

20-25




150

300






200

550






250

820






300

1080






350

1480

10,000-12,000




0150


1420





0155

350

1520











Stop-restart


355

1495





0200

355






0205

355







100





Torque up/stop

0210

200







250

930






350

1500




Torquing up

0220

350

1470



8-11k


0226

350

1485




1 m penetration

0235






Torque up and stall, can't get bit to rotate, stuck







40 k over pull







Lower to bottom to see if hammering can free bit

0245

400

1720



24k

40 k overpull

0300






Working pipe and hammering to free pipe

0315






One-third left-hand rotation frees bit

0320






Clear seafloor

0350






Observe wings on bit have come unwelded, pull camera

Notes: Water depth = 740 mbrf; bit = Holte concentric with arms welded shut.

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