Abstract:Catenary shape profile is a classical type of extended reach well; a nonlinear equation with the initial well oblique angle as unknown factor should be solved for its design. As this unknown factor exists in several triangular functions and logarithmic functions, large amount of calculation is required; and commonused interative solution method is not so ideal. The nonlinear equation is changed to a new one only with logarithmic function and polynomial function, to which geometric analysis is made on the function character, and step search algorithm and adaptive step search algorithm are proposed for solution interval. Numerical solution of new equation can be got rapidly in solution interval by dichotomy. The effectiveness of the above algorithm was proved by the design case of extended reach well, and relationship between hole curvature in arc well section and equation solution was discussed. The algorithm introduced in this paper can be applied in the development of computer software for the design on extended reach well trajectory.

Abstract:We have consturcted 5 coalbed methane wells（there are 4 parameter wells) in Sichuan. The parameters reflected the procession of reservoir condition for coalbed methane development and small network of production test in Sichuan. But there are still serious existing problems such as slow drilling process, difficult layer selection for setting test and hole deviation control, coal seam correlation and coal recovery not ideal as expected and coal reservoir pollution. Three spuds well structure, deviation control with drilling straight, research on large diameter wireline coring and reservoir protection were suggested by the condition analysis to promote the drilling technical guarantee for coalbed methane exploration and development in Sichuan.

Abstract:Teriary strutum in Central Hebei is mainly of purplishred mudstone and fine grey sandstone with strong mudstone mud making, some formations are very unstable, which make drilling construction difficult with drill bolcking. The paper summed up the prevention measures for complicated accident in horizontal well construction with a successful treatment case, which could be the reference to horizontal well construction in Central Hebei district and other places.

Abstract:There are a lot of softwares available for directional drilling trajectory design and control. Based on the Excel calculation formula and graphical functions, Excel program of directional intersected well was compiled for convenient application, which was proved by field applications that it could satisfy the calculation accuracy for directional intersected well. This simple and easy program provides realtime decision of drilling trajectory through formation by the relation of formation information with the error greatly reduced at the end of the buildup portion. Application of Excel in directional intersected well is instructive to the accurate design and construction of longreach horizontal directional well, directional well and trenchless engineering.

Abstract:DP4 well is a horizontal one, locating at the Daniudi gas field of Ordos Basin and drilled with aerated underbalanced drilling technology. The target formation is He 1 with lower formation pressure coefficient from 0.83 to 0.99(average 0.93). To effectively protect He 1 formation, aerated underbalanced drilling technology was implemented in the whole horizontal section with aerated drilling fluid, and the protection was successful. The paper mainly introduced the aerated underbalanced drilling fluid about the technique & technology, implemetation process and the field situation; and also analyzed and evaluated implemetation effect of aerated underbalanced drilling fluid in this well.

Abstract:In order to explore effective development adjustment method for fractured low permeability oilfield, mitigate production decline and improve ultimate recovery, sidetrack horizontal well tests were made on long time shutin oil and water wells to improve oil extraction rate and producing degree of residual oil, which provided technical basis to the followup adjustment for low abundance, low permeability fractured oil field.

Abstract:Improving drilling efficiency in medium-deep hole is key point for coring drilling construction, especially for the medium-deep holes of 500-1000m. With the deep drilling case of Sijiaying iron mine, the paper discussed the construction method and the experience.

Abstract:On the basis of the summary on the advantages of aluminum alloy drilling pipe, this paper introduced connection methods and interference fit for aluminum alloy drilling pipe and steel joint in new national standard. Some examples were given to illustrate the advantages for adopting aluminum alloy drilling pipe in deep wells, which can evidently decrease hook load, rotary torque and pumping pressure loss. Finally, the paper discussed application prospects of aluminum alloy drilling pipe in deep holes for geological exploration.

Abstract:Water swivel is an important component for XY series of core drill with function to connect the hose and the internal channel of driving pipe, and to realize dynamic and static state transition. In the long-term use，it was found easy to leak, and inconvenient for maintenance. This article introduces the improvement on water swivel based on the prototype structure，with a merit of non-dismantling while repairing, long service life and higher operation efficiency.

Abstract:According to the situation of a large-scale Hangzhou subway Genshanmen station with underpass road, flood control channel, shield launching shaft and surrounding high-rise buildings, by the study on deep excavation construction, analysis was made on the cause of excavation warning with corresponding countermeasures and the experience was summed up as reference for the similar subway station construction in Hangzhou.

Abstract:The paper discussed the construction method of pile-anchor combination and soil-nailing wall for deep excavation in complex conditions with engineering cases. A feasible construction method was explored for the similar engineering.

Abstract:The radial well is an effective method for draft water by riverside and experimental study was made with the engineering case in Futunxi beach land. The paper described the design method, discharge calculation, construction technology and water quality of test of well radial well for draft water by riverside.

Abstract:The paper introcuced the drilling construction technology of Shanghai-Chengdu high speed railway in karst strutum, together with the equipments selection, technical parameters determination and the treatment & prevention for commom accidences of drilling construction in such strutum.

Abstract:With the development of underground space engineering, super-deep underground diaphragm wall becomes more and more popular, consequently resulting in the increasing risk in construction. This paper discussed and analyzed the construction technology of super-deep underground diaphragm and the existing problems according to the field experience with the relevant solving methods. In a word, by untilizing the proper technologies, the engineering of super-deep underground diaphragm wall can be successfully conform to the design reqirments.

Abstract:The paper discussed the treatment for a complicated accident of drill blocking in a large diameter deep hole, detailed the whole process and treatment method and summed up the experience.

Abstract:This article describes the basic characteristics of loess; and with engineering cases illustrates the mechanism, construction technology and effect on application of rammed soil-cement pile in collapsible loess foundation treatment; and provides reference for the the application in local area with the attentions in construction.

Abstract:In an existing bridge pier reinforcement engineering in Liuzhou City, verticle pre-stressed cables were constructed by drilling in bridge piers to increase safety factors. This engineering case provided reference to the design and construction of existing bridge pier reinforcement.

Abstract:The paper presented a horizontal well construction case in Hebei Province with non-excavated guide pipeline installation technology and introduced the construction method in detail.

Abstract:The paper introduced the eccentric simultaneous casing drilling technology about hole making, construction facilities and the corresponding technical measures in high slope broken layer of Xi’an to Ankang expressway.

Abstract:By the half-analytic calculation method, the paper analyzed the tunnel circumjacent constringency and vault settlement with time and alteration depth of tunnel face, the relevant constringency model was built, and the reasonable second support time for hard and soft rock tunnel were proposed. With the engineering case, the least-squares fitting calculation was made on circumjacent constringency of Ⅱ、Ⅲ、Ⅳ、Ⅴ grade of rocks, and the reasonable support time for these 4 grades of rock were obtained.

Abstract:The paper reviewed the design and quality control of nuclear island negative excavation blasting around a conmmercial operation nuclear power station, especially described presplitting blasting of negative excavation, the nuclear island corridor blasting technology and key points of the quality control.

Abstract:The machine station, which is engaged in coal bed methane exploration, should take the reference on “Healthy-Safety-Environment Management Guide for Industry of Oil and Natural Gas”（SY/T6283-1997）. The paper introduced HSE management in coal bed methane exploration with the case of XY-5 coring drill in an exploration hole in North Shaanxi.