Fuzzy discrimination of lithology while drilling with PDC bit;

In order to obtain higher data transmitting rate and the wireless transmitting technology while drilling with less influence by working condition,an analysis and discussion were made for acoustic telemetry while drilling in channel transmission characteristic,noise and inter-symbol interference,transducer and power supply,and some key factors during drilling deep/ultra-deep well.

The comparison between logging while drilling(LWD) and wireline logging(WL) curves of a oilfield shows that: the depth,value of resistivity,and distribution range of density of the LWD measurements are rather close to that of WL,invasion effect in LWD is less than that in WL,so LWD can provide more credible information for oil-gas interpretation and formation evaluation.

Intense electromagnetic interference while drilling prevents traditional analog phase sensitive demodulation(APSD) from correctly acquiring electromagnetic wave signal of logging while drilling(LWD).

Introduced are specialities,structures and parameters of some newly developed Logging While Drilling(LWD)tools used by eminent well logging companies in the past few years,such as quadrupole shear wave technology,multipole sonic tools,compact propagation resistivity tool,azimuthal focused resistivity sensor,azimuthal deep resistivity tool,etc.

According to the grey theory,a new method of pore pressure prediction for undrilled formation beneath the bit was offered in the thesis,and a grey model of formation pore pressure prediction while drilling was es.

Several methods have been used in pre-drilling pressure prediction, prediction while drilling and monitoring.

Reasearch of measurement while drilling and azimuth correction for horizontal directional drilling;

Advances in technology for electromagnetic measurement while drilling in China;

The measurement while drilling technology in nearly horizontal directional drilling in coal mines

Using LWD Logs to Guide Horizontal Well Drilling;

Application of LWD PeriScope to Horizontal Well Development in Karamay Oil Field;

Design of a general memory module of large capacity for down-hole LWD tools;

The formation pressure detection while drilling plays a significant role in the aspects of protecting oil and gas reservoir, insuring drilling safety,determining hole structure and etc.