Field test results of a 12-1/4 " fluid hammer tool are presented. This field test was conducted in the shallow section of the intermediate hole (4500') through the Barranqu?n Formation, which is the hardest and abrasive section within the Alochtonous Cretaceous Block, Eastern Venezuela. Test's principal objectives were to understand tool's performance under specific and controlled drilling parameters.
This trial is the second one conducted in the same formation. It was planned and operated in order to reduce the associated risk of testing new drilling technologies. Careful attention was given to choose a well section and operations schema that assured a maximum control over the field test.
Test results and field observation show a strong relationship between hammer, drillstring and drilling parameters on tool's performance. The driller operated the hammer with conventional drilling equipments and procedures. He drilled with low Weight on Bit (WOB), and low rotational speeds (RPM). Flow rates increased accordingly to keep Stand Pipe Pressures (SPP) and differential pressure through the hammer constant. However, keeping them as planned was difficult. The test lasted 5 hours in which the equipment drilled 20 ft for an overall rate of penetration (ROP) about 4 ft/hr. Instantaneous ROP were higher than offset wells (5.5 ft/hr) but a better understanding of the whole system must be carried out in order to further develop an entire system that can sustain a constant and high ROP.