Two breakthroughs for key technology have emerged. - the establishment of a downhole tee at branch connection points and a branch string lateral re-entry. A “DF-1” patent technology has been successfully developed to form two tool series at 9 5/8″ and 7″, and applied in TAML 5 level well completion. Over 50 multi-lateral wells covering various types can now be run each year.

Many significant achievements have been reached using supporting technologies such as window cutting sidetracking, well trajectory control, and well completion tool manufacturing. These include directional window cutting and sidetracking optimization design, micro-step reaming for small sidetracking borehole, narrow-space casing centralization in small borehole, small size thermal stress compensating well completion, displacement technology for cement injection in narrow-space small borehole, cementing technique in different-diameter small borehole, and more. A series of supporting tools with proprietary intellectual property rights have been developed including series window cutting milling cone, whipstocks, micro-step reaming tools, integrated window cutting sidetracking tools, hydraulic-sealed liner hangers, liner pre-stress devices, and hydraulic centralizer. The integrated technology reaches leading positions in the world forming an annual operating capacity of 200 wells.

Several sets of low-density water-based micro-foam drilling fluid composition systems have been developed to satisfy the requirements of foam drilling under different geological conditions. The low-density water-based coarse foam plugging system along with foam drilling fluid recycling have been successfully tested on site. The challenge that air foam drilling can not be used for gas formation has been over come as the micro-foam drilling fluid has been successfully used for drilling high-output gas formation. Regarding the stability problem of foam fluid under ultra-high temperature condition, we have resolved and applied the solution in high-temperature geothermal wells. We have also developed a technology for preventing the erosion and corrosion of air drilling tools during air drilling.

GWDC has developed various coring tools covering 10 technical series and 30 types to meet the requirements of drilling coring operation in unconsolidated formations, gravel formations, middle-hard and hard formations and coal beds. The technology has reached the leading position in China.

Our Special drilling fluid technology includes water-based series, oil-based series and foam series designs. Thirteen of our typical drilling fluid systems are: KCL-polymer drilling fluid, KCL-silicate drilling fluid, saturated saltwater drilling fluid, high-temperature resistant organic silicon drilling fluid, high-temperature and high-density drilling fluid, strong-restraining and anti-collapse drilling fluid, environmental water-based drilling fluid, high-effective reservoir protecting drilling fluid, oil-in-water drilling fluid, fully oil-based drilling fluid, water-in-oil drilling fluid, recyclable micro-foam drilling fluid, and air-foam drilling fluid. These enhance the effectiveness for increasing drilling speed, protecting oil and gas bearing formations and reducing drilling cost.

The Logging Express Acquisition Platform (LEAP800) is a new generation well logging system mainly developed on the basis of LEAP600B, GWDC has the proprietary intellectual property rights of this system under international law. This system can quickly and accurately gather formation data and deliver enhanced formation images and data processing service, and supports all downhole service items of wireline logging, including conventional in open and cased hole, imaging logging, formation pressure testing, perforation coring, etc..

GWDC has developed ‘through casing resistivity logging tool’ with a breakthrough in key technologies such as weak signal measurement, signal synchronous transmission, circuit design, power supply electrode design, measuring electrode design and hydraulic pushing system design. This tool is used with LEAP800 logging platform, an interpretation model has been established, and a corresponding data processing and interpretation software has been developed. This tool has been successful tested in 188 wells to obtain good logging data.

GWDC has developed the GW-MLE all-inclusive mud logging equipment. By adopting a positive-pressure anti-explosive and fire-proof (A-0 level) instrument cabinet, this equipment is applicable for onshore and offshore exploration. The broadband and broad-voltage power supply system is in accordance with corresponding international and Chinese standards.

In order to solve the technical difficulty in high H₂S well testing, we carried out a series of technical research and operation process optimizations based on risk identification and analysis, and finally achieved sealed operation in the whole testing process with the help of remote real time monitoring.