Su 76-1-20H

Using Report of HT-LWD350 Instrument for Large Horizontal Well

Well Number: Su 76-1-20H Drilling Crew: Bohai Drilling 50251
Instrument Style: HT-LWD 350

Description of Well Condition:
Su 76-1-20H located in Su20 area of Changqing Oilfield, is designed as third spud horizontal well. Its borehole size is 152mm, measured depth is 5445m, program horizontal section is 2000m, and pay zone thickness is 1m which increases difficulty for construction of while drilling instruments.
Operating Situation of HT-MWD350:
1.On 16:00 August 2 2011, the instrument was descended into well. The initial well depth was 3490m, and bottom static temperature was 110℃. Till September 9 2011, when the instrument was taken out, the well depth was 5445m. The instrument operated 862 hours.
2. After the down-hole instrument was taken out, disassembled and checked, the pulser and probe’s ground tests showed normal. Spare parts was normal without any erosion.
3. After descending instrument into well, there were 12 trips done when well depth is from 3490m to 5445m. The instruments worked downhole 862 hours without any failure. The natural gamma of instrument played an important role in drilling the horizontal section. Meanwhile, owner could precisely tell the position from combining gas survey data and gamma ray curve which significantly saved drilling period.
4. HT-MWD350\LWD350 with high stability, high precision for measurement and low fault rate, which gained owner’s consistent praise. Besides, it created new drilling time record for this drilling crew.