The gamma-ray attenuation porosity evaluator (GRAPE) component of the multisensor track (MST) unit on board the JOIDES Resolution measures the saturated bulk density of sediments by relating the attenuation of gamma rays in a core sample to that of a standard with known density (aluminum). After reaching thermal equilibrium, unsplit core sections are routinely run through the MST system. The sa...

Physical and geochemical characteristics of shale play conclusive role in confirming operation measures during drilling and stimulation. The properties of shale samples from Jiyang depression were investigated through X-ray diffraction, scanning electron microscope, adsorption isothermal, high pressure mercury intrusion, methylene blue trihydrate, pressure pulse decay, tests of specific water w...

Downhole vibrations caused by rock breaking when drilling through pebbled sandstone formations negatively affect the rate of penetration (ROP) and safety downhole tools. Therefore, it is great significance to study cutting characteristics find a method reducing formations. Based on DEM (discrete element method), simulation model considering random filling high-strength gravels was established u...

In drilling engineering, the wear of tribo-pairs is primary cause for rapid failure rotating seals in pneumatic downhole tools. order to reduce tribo-pairs, a new type was designed this work, which introduced copper alloys between stator and rotor. To elucidate mechanism copper-steel tribo-pair motors, pin-on-disc dry sliding tests with Qbe-2 beryllium bronze pin against 38CrMoAlA steel disc un...

As part of the ANDRILL McMurdo Ice Shelf (MIS) Project two comprehensive sets of geophysical data were collected on ice at the AND-1B drillsite. Whole-core physical properties were determined with high vertical resolution to a depth of 1285 mbsf. A multi-sensor-core-logger was used to determine bulk density, sonic velocity, magnetic susceptibility and electrical resistivity. After drilling, a s...

High-efficiency rock-breaking is a problem that has long been studied in the oil- and gas-drilling industry. The successful use of ultrasonic technology related fields prompted us to study how introduce into oil gas drilling. This paper introduces discusses cases breaking fields, summarizes three basic forms action on rocks, namely, resonance, impact cavitation, expounds factors laws affect ult...