China-made Rigs Enter International Market

Nowadays, China＇s drilling equipment manufacturing has formed into a sophisticated industrial chain, playing an indispensable role in supporting China＇s petroleum industry. Especially in recent years, apart from satisfying the requirements of domestic onshore drilling operations, the state-of-the-art drilling equipments like offshore modular drilling rigs, 9000 meter ultra-deep rigs have also been successfully manufactured, this, together with the wholesale export of electric drilling rigs to the overseas market, has ranked China as a primary manufacturer of drilling equipments in the world. China can now wholesale produce series of onshore and offshore drilling equipment with rig production of nearly 200 per year. The production capacity accounts for 20%-25% of the world total. In addition to satisfying domestic market, China made onshore drilling rigs have also gained great competitive advantages in the international market.     

Siemens to Construct Offshore Oil Platform in China

As it seeks to expand its oil and gas business in the market, German industrial giant has recently waon won a tender for a 35-million-euro （USS44.74 million） project in China, which a involves the construction of an offshore drilling platform. The project was awarded to Siemens by Yantai Raffles Shipyard in Shandong Province.     

Development Status and Challenge of PetroChina＇s Deep Drilling Technologies

Deep and ultra-deep drilling technologies have been developed since the late 1930s, and got great achievements especially in the last two decades. The depth of well completion has even reached to 12 kilometers. Several countries, such as US and some European countries, are leading in the advanced deep and ultra-deep drilling technologies in the world. In recent years, nevertheless, PetroChina has also made big progress in mechanical penetration rate （ROP）, drilling period, amount of drilling bit used in a single well of deep drilling as well as in deep drilling equipments. Compared with the high-level technologies of complicated deep drilling in the world, PetroChina still has a long way to go.     

GWDC Remarkable for Overseas Operation—Execution of Iranian project by GWDC

Great Wall Drilling Company (GWDC) of CNPC has made brilliant achievements in expanding overseas drilling market in the recent years. In the beginning of 2001, when the company was restructured for its specialized business with the new corporate management put in place, GWDC started to involved itself in the 19+2 drilling project in Iran.     

Properties and testing of a hydraulic pulse jet and its application in offshore drilling

Offshore drilling has attracted more attention than ever before due to the increasing worldwide energy demand especially in China. High cost, long drilling cycles, and low rate of penetration （ROP） represent critical challenges for offshore drilling operations. The hydraulic pulse generator was specifically designed, based on China offshore drilling technologies and parameters, to overcome problems encountered during offshore drilling. Both laboratory and field tests were conducted to collect the characteristics of the hydraulic pulse generator. The relationships between flow rate and pressure amplitude, pressure loss and pulse frequency were obtained, which can be used to optimize operation parameters for hydraulic pulse jet drilling. Meanwhile a bottom hole assembly （BHA） for pulse jet drilling has been designed, combining the hydraulic pulse generator with the conventional BHA, positive displacement motor, and rotary steerable system （RSS） etc. Furthermore, the hydraulic pulse jet technique has been successfully applied in more than 10 offshore wells in China. The depth of the applied wells ranged from 2,000 m to 4,100 m with drilling bit diameters of 311 mm and 216 mm. The field application results showed that hydraulic pulse jet technique was feasible for various bit types and formations, and that ROP could be significantly increased, by more than 25%.     

GDWG Operates 100 Drilling Rigs Worldwide

Great Wall Drilling Company (GWDC) has become part of the main forces of CNPC in development of international market since it was reorganized three years ago, according to the information made available from the 2004 work conference of the drilling company.     

Research on deepwater synthetic drilling fluid and its low temperature rheological properties

With the rapid development of deepwater drilling operations,more and more complex technical challenges have to be faced due to the rigorous conditions encountered.One of these challenges is that the drilling fluid used must had good rheological properties at low temperatures and high ability to inhibit hydrate formation.Synthetic drilling fluid has been widely applied to deepwater drilling operations due to its high penetration rate,excellent rheological properties,good ability to prevent hydrate formation,and high biodegradability.A synthetic drilling fluid formulation was developed in our laboratory.The rheological properties of this drilling fluid at low temperatures (0-20 °C) were tested with a 6-speed viscometer and its ability to inhibit hydrate formation was evaluated at 20 MPa CH 4 gas and 0 °C by differential scanning calorimetry (DSC).Several factors influencing the low temperature rheological properties of this synthetic drilling fluid were studied in this paper.These included the viscosity of the base fluid,the amount of CEMU and organic clay,and the water volume fraction.     

Drilling cost optimization in a hydrocarbon field by combination of comparative and mathematical methods

In drilling operation,a large saving in time and money would be achieved by reducing the drilling time,since some of the costs are time-dependent.Drilling time could be minimized by raising the penetration rate.In the comparative optimization method,by using the records of the first drilled wells and comparing the criteria like penetration rate,cost per foot and specific energy,the drilling parameters of the next wells being drilled can be optimized in each depth interval.In the mathematical optimization technique,some numerical equations to model the penetration rate,bit wear rate and hydraulics would be used to minimize the drilling cost and time as much as possible and improve the results of the primary comparative optimization.In this research,as a case study the Iranian Khangiran gas field has been evaluated to optimize the drilling costs.A combination of the mentioned optimization techniques resulted in an optimal well which reduced the drilling time and cost considerably in comparison with the wells already drilled.     

Development Status and Challenge of PetroChina’s Deep Drilling Technologies

Deep and ultra-deep drilling technologies have been developed since the late 1930s, and got great achievements especially in the last two decades. The depth of well completion has even reached to 12 kilometers. Several countries, such as US and some European countries, are leading in the advanced deep and ultra-deep drilling technologies in the world. In recent years, nevertheless, PetroChina has also made big progress in mechanical penetration rate (ROP), drilling period, amount of drillin…     

Soaring in International Market

The international market share and economy benefits of ZPEB （Zhongyuan Petroleum Exploration Bureau, Sinopec ） are presenting an unprecedented development tendency currently, which holds 83 engineering crews with more than 2000 people have been working in more than 7 countries in the world, including Sudan, Indonesia, Saudi Arabia, Yemen, Qatar, Ecuador, Kazakhstan, Nigeria etc, involving drilling, well workover, geophysical survey, well cementation and other technique service projects. In recent years, all these projects have been rapidly developed, taking the last year 2005 as an example, the volume of engineering contracts signed last year increased 48% over the year 2004, reached to hundreds of millions US dollars, accounted for 44% of contract volume signed by Sinopec in the same year. There are 24 new crews sent to international market last year, and it means that one drilling crew and ano ther one engineering crew each month could be sent to foreign countries, now the number of the drilling and workover crews is up to 50 at abroad.     

Research into magnetic guidance technology for directional drilling in SAGD horizontal wells

SAGD horizontal wells are used to enhance oil recovery from heavy oil reservoirs.This technology requires precise separation between the production well and the injection well to ensure the efficient drainage of the reservoir.By studying the attitude of the downhole probe tube and the production well trajectory,an algorithm is proposed for eliminating ferromagnetic interference while drilling injection wells.A high accuracy filter circuit has been designed to correct the detected magnetic signals,which are ultra-weak,frequency-instable,and narrow-band.The directional drilling magnetic guidance system(DD-MGS) has been developed by integrating these advanced techniques.It contains a sub-system for the ranging calculation software,a magnetic source,a downhole probe tube and a sub-system for collecting & processing the detected signals.The DD-MGS has succeeded in oilfield applications.It can guide the directional drilling trajectory not only in the horizontal section but also in the build section of horizontal injection wells.This new technology has broad potential applications.     

Experimental study of low-damage drilling fluid to minimize waterblocking of low-permeability gas reservoirs

This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Based on investigation of the geological characteristics and the potential formation damage of the Permian formation of the reservoir, waterblocking due to invasion of drilling or completion fluids was identified one of the most severe causes of damage to gas well deliverability. By adopting the phase trap prevention method, ideal packing theory, and film-forming technology, a lowdamage drilling fluid, sodium formate brine containing efficient waterblocking preventing surfactants, optimized temporary bridging agents （TBAs）, and film-forming agents has been developed. The performance of the new drilling fluid was evaluated by using a variety of techniques. The results show that the fluid has good rheological properties, good strong shale-swelling inhibition, good temporary plugging effect, ultra-low filtration, and good lubricity. It can efficiently minimize waterblocking and can be used to drill horizontal wells with minimal intervention of the reservoir in the Sulige Gas Field.     

Development and Application of Hydraulic/Mechanical Drilling Jar and Mechanical Shock Absorber

Introduction Since 1990s,due to the development of petroleum exploration technology,petroleum machinery and equipment have been addressed by all nations.By means of heavier investment on technology innovation,adopting advanced technology to develop new equipments by big oil companies,the overall levels of adaptability,reliability,diversity, seriation,integrity,automatization,intelligence are highly improved.In recent years,the technology of exploration and development for oil and gas in China has expanded rapidly,while the technique of drilling and production is approaching world level.As the drilling engineering orients to the directional well,ultra-deep well and complex well,the research and development of downhole tools to match the technique has shown its importance.     

Risk analysis of extended reach wells in the Liuhua Oilfield,South China Sea,based on comprehensive fuzzy evaluation method

Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling （ERD） is very important to prevent complex failures and to improve drilling efficiency. Nowadays there are few reports on how to analyze quantitatively the drilling risk for extended reach wells （ERWs）. Based on the fuzzy set theory, a comprehensive fuzzy evaluation model for analyzing risks of ERD is proposed in this paper. Well B6ERW07 is a planned 8,000-meter ERW with a high ratio of horizontal displacement （HD） to vertical depth （VD） in the Liuhua Oilfield, the South China Sea, China. On the basis of the evaluation model developed in this study, the risk for drilling Well B6ERW07 was evaluated before drilling. The evaluation result shows that the success rate of drilling this well is predicted to be 51.9%, providing important rational and scientific information for the decisionmakers.     

Change and Development of the International Natural Gas Market in the New Situation

<正>This year, due to geopolitical factors, concerns in the European natural gas market have intensified and spread to the Asian market. Europe has taken the measure of increasing LNG imports to make up for the decline in pipeline gas imports, and LNG imports from the United States have increased substantially, resulting in tightened supply and demand in the United States. The supply and demand of the global natural gas market are expected to be increasingly tight throughout the year.     

Development and applications of solids-free oil-in-water drilling fluids

The increasing application of near balanced drilling technology to low-pressure and depleted fractured reservoirs requires the use of low-density drilling fluids to avoid formation damage. Solidsfree oil-in-water （O/W） emulsion drilling fluid is one type of low-density drilling fluid suitable for depleted fractured reservoirs. In this paper, the solids-free O/W drilling fluid was developed and has been successfully used in the Bozhong 28-1 oil and gas field, by which lost circulation, a severe problem occurred previously when drilling into fractured reservoir beds, was controlled, thereby minimizing formation damage. The O/W emulsion drilling fluid was prepared by adding 20% （by volume） No. 5 mineral oil （with high flash point, as dispersed phase） into seawater （as continuous phase）. Surfactant HTO-1 （as a primary emulsifier） and non-ionic surfactant HTO-2 （as a secondary emulsifier） were added into the drilling fluid system to stabilize the emulsion; and YJD polymer was also added to seawater to improve the viscosity of the continuous phase （seawater）. The drilling fluid was characterized by high flash point, good thermal stability and high stability to crude oil contamination.     

Global Natural Gas Market Review and Outlook

正The global natural gas market has developed rapidly over the past five years and it still has some evident regional characteristics. North America, Europe and Asia Pacific have formed three major markets with different regional characteristics according to their own resource endowments. In the future, the global natural gas market as well as the process of globalization will both continue to develop further as countries move towards their carbon neutrality goals. Meanwhile, natural gas and renewable energy will complement each other to achieve integrative development.This paper mainly reviews the development of the international natural gas market over the past five years and makes predictions for the next five years.     

BAOJI OILFIELD MACHINERY CO.,LTD.

Baoji Oilficld Machinery Co.,Ltd （BOMCO） now is the largest oilfield equipment manufacturer under China National Petroleum Corperation （CNPC）.BOMCO now has over 3400 employees,including more than 740 engineers .possesses various equipmems over 2000 sets .MOMCO manufactures and distributes over 50 varieties and 1000 speeifications oilfield drilling equipment such as drilling rigs,mud pumps etc for onland and offshore and poessesses over 50% market of oilfield machin in China .     

High temperature and high pressure rheological properties of high-density water-based drilling fluids for deep wells

To maintain tight control over rheological properties of high-density water-based drilling fluids, it is essential to understand the factors influencing the rheology of water-based drilling fluids. This paper examines temperature effects on the rheological properties of two types of high-density water-based drilling fluids (fresh water-based and brine-based) under high temperature and high pressure (HTHP) with a Fann 50SL rheometer. On the basis of the water-based drilling fluid systems formulated in laboratory, this paper mainly describes the influences of different types and concentration of clay, the content of a colloid stabilizer named GHJ-1 and fluid density on the rheological parameters such as viscosity and shear stress. In addition, the effects of aging temperature and aging time of the drilling fluid on these parameters were also examined. Clay content and proportions for different densities of brine-based fluids were recommended to effectively regulate the rheological properties. Four rheological models, the Bingham, power law, Casson and H-B models, were employed to fit the rheological parameters. It turns out that the H-B model was the best one to describe the rheological properties of the high-density drilling fluid under HTHP conditions and power law model produced the worst fit. In addition, a new mathematical model that describes the apparent viscosity as a function of temperature and pressure was established and has been applied on site.     

Numerical analysis of the effects of downhole dynamic conditions on formation testing while drilling

Formation testing while drilling is an innovative technique that is replacing conventional pressure testing in which the fluid sampling is conducted in a relatively short time following the drilling. At this time, mud invasion has just started, mudcake has not formed entirely and the formation pressure is not stable. Therefore, it is important to study the influence of the downhole dynamic environment on pressure testing and fluid sampling. This paper applies an oil-water two phase finite element model to study the influence of mudcake quality and mud filtrate invasion on supercharge pressure, pretest and sampling in the reservoirs of different permeability. However, the study is only for the cases with water based mud in the wellbore. The results illustrate that the mudcake quality has a significant influence on the supercharge pressure and fluid sampling, while the level of mud filtrate invasion has a strong impact on pressure testing and sampling. In addition, in-situ formation pressure testing is more difficult in low permeability reservoirs as the mud filtrate invasion is deeper and therefore degrades the quality of fluid sampling. Finally, a field example from an oil field on the Alaskan North Slope is presented to validate the numerical studies of the effects of downhole dynamic conditions on formation testing while drilling.