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3 Status Quo of Methods for Evaluating Filtration Performance and Mud Cake Quality of Drilling Fluid
4 Drilling Fluid Technology for “Three High” Wells in Qaidam Basin in Qinghai
5 Progresses in Studying Drilling Fluid Nano Material Plugging Agents
6 Plugging Micro-fractures to Prevent Gas-cut in Fractured Gas Reservoir Drilling
7 A New Fracturing Fluid with Temperature Resistance of 230℃
8 Progress in Studying Cement Sheath Failure in Perforated Wells
9 Development of Extreme Pressure Anti-wear Lubricant MPA for Water Base Drilling Fluids
10 A Temperature Sensitive Expanding Microcapsule Anti-Gas-Channeling Cement Slurry
2 Study and Performance Evaluation of Ultra-High Temperature High Density Oil Based Drilling Fluids
3 Synthesis and Evaluation of A Primary Emulsifier for High Temperature Oil Base Drilling Fluid
4 Progresses in Studying Drilling Fluid Nano Material Plugging Agents
7 High Performance Water Base Drilling Fluid for Shale Gas Drilling
8 High Performance Water Base Drilling Fluid for Shale Gas Drilling
9 Study on Hydrophobic Nano Calcium Carbonate Drilling Fluid
Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
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2023, 40(1): 1-19.
doi: 10.12358/j.issn.1001-5620.2023.01.001
Abstract:
Although progresses made in horizontal drilling have been very beneficial to the development of conventional and unconventional oil and gas, two factors related to the cleaning of drilled cuttings from the horizontal section of a well seriously hinder the drilling operation. One of the factors is borehole wall instability, and the other is the difficulties in wellbore cleaning. Inability to remove drilled cuttings from a wellbore in a timely manner often results in increases in friction and torque on the downhole drill string, and the frequency of pipe sticking, and the worse is the simultaneous occurrence of lost circulation. First in this paper, the causes of cuttings bed formation and technical parameters for field operation are analyzed and summarized from two aspects, which are hole cleaning mechanisms and the main factors affecting hole cleaning (mud rheology, pipe rotation, hole inclination, sizes of the drilled cuttings, mud weight and flowrate etc.). Second, the methods and mechanisms of cuttings removal were systematically elaborated from the drilling fluid technologies and hole cleaning tools available both in China and abroad to help deal with the difficulties in hole cleaning in deviated and horizontal drilling. Finally, the development direction for horizontal and deviated hole cleaning technology is prospected to provide a reference for the hole cleaning technology development in the future.
Although progresses made in horizontal drilling have been very beneficial to the development of conventional and unconventional oil and gas, two factors related to the cleaning of drilled cuttings from the horizontal section of a well seriously hinder the drilling operation. One of the factors is borehole wall instability, and the other is the difficulties in wellbore cleaning. Inability to remove drilled cuttings from a wellbore in a timely manner often results in increases in friction and torque on the downhole drill string, and the frequency of pipe sticking, and the worse is the simultaneous occurrence of lost circulation. First in this paper, the causes of cuttings bed formation and technical parameters for field operation are analyzed and summarized from two aspects, which are hole cleaning mechanisms and the main factors affecting hole cleaning (mud rheology, pipe rotation, hole inclination, sizes of the drilled cuttings, mud weight and flowrate etc.). Second, the methods and mechanisms of cuttings removal were systematically elaborated from the drilling fluid technologies and hole cleaning tools available both in China and abroad to help deal with the difficulties in hole cleaning in deviated and horizontal drilling. Finally, the development direction for horizontal and deviated hole cleaning technology is prospected to provide a reference for the hole cleaning technology development in the future.
2023, 40(1): 20-27.
doi: 10.12358/j.issn.1001-5620.2023.01.002
Abstract:
In deep and ultra-deep drilling, weighting materials are added to the drilling fluids to produce a pressure that is enough to balance the formation pressure. Weighting materials added to a drilling fluid can adsorb water and additives, thus affecting and even exacerbating the properties of the drilling fluid. To investigate the form and adsorptive characteristics of weighting materials in a drilling fluid, a method of measuring the specific surface area of a weighting material in a liquid has been established based on low-field nuclear-magnetic resonance (LF-NMR). The specific surface area of a weighting material in water based drilling fluids with densities between 1.1 g/cm3 and 2.4 g/cm3 and the specific surface area of the same weighting material in dry powder state, and the change of the specific surface area of the weighting material in liquid and as dry powder were analyzed using the LF-NMR method and particle size estimation method. The adsorption capacity of a weighting material in fluids of different densities were investigated through organic carbon adsorption experiment and rheology measurement. It was found that the weighting material in fluids of different densities has different adsorption capacities for different mud additives. In three 500 mL drilling fluids, each of which has a density of 1.2 g/cm3, 1.8 g/cm3 and 2.4 g/cm3, respectively, the adsorption capacities of the weighting material for sulfonated lignite were 10.83 g, 13.06 g and 17.69 g, respectively. This testing result can be correlated with the specific surface area results obtained with LF-NMR.
In deep and ultra-deep drilling, weighting materials are added to the drilling fluids to produce a pressure that is enough to balance the formation pressure. Weighting materials added to a drilling fluid can adsorb water and additives, thus affecting and even exacerbating the properties of the drilling fluid. To investigate the form and adsorptive characteristics of weighting materials in a drilling fluid, a method of measuring the specific surface area of a weighting material in a liquid has been established based on low-field nuclear-magnetic resonance (LF-NMR). The specific surface area of a weighting material in water based drilling fluids with densities between 1.1 g/cm3 and 2.4 g/cm3 and the specific surface area of the same weighting material in dry powder state, and the change of the specific surface area of the weighting material in liquid and as dry powder were analyzed using the LF-NMR method and particle size estimation method. The adsorption capacity of a weighting material in fluids of different densities were investigated through organic carbon adsorption experiment and rheology measurement. It was found that the weighting material in fluids of different densities has different adsorption capacities for different mud additives. In three 500 mL drilling fluids, each of which has a density of 1.2 g/cm3, 1.8 g/cm3 and 2.4 g/cm3, respectively, the adsorption capacities of the weighting material for sulfonated lignite were 10.83 g, 13.06 g and 17.69 g, respectively. This testing result can be correlated with the specific surface area results obtained with LF-NMR.
2023, 40(1): 28-34.
doi: 10.12358/j.issn.1001-5620.2023.01.003
Abstract:
In a Pickering emulsion, the solid particle emulsifier is absorbed at the interface between oil and water, forming a stable interfacial film to prevent the coalescence of water droplets. This property can be used to improve the stability of oil based drilling fluids. However, in studies on the oil based drilling fluids based on Pickering emulsion, the interaction between a water droplet in the oil phase and an inorganic hydrophilic particle has been omitted; the effects of inorganic particles added to an oil based drilling fluid, such as calcium hydroxide, weighting agents and the drilled cuttings, on the existence of the water droplets in the emulsion are not considered. In laboratory study, calcium hydroxide, barite and kaolinite particles of different hydrating capacities were added into a W/O Pickering emulsion. Macro sedimentation experiment and microscope observation with microscopic images have proved that the water droplets are combined with the solid particles, existing in a form of bound water. This explains the aggregation of the solid particles. The bound water was characterized with laser confocal microscope and low temperature differential scanning calorimetry. The solid particles with bound water can be dispersed by treating the system with a dispersant, in this way the stability of the drilling fluid can be improved. An oil based drilling fluid based on W/O Pickering emulsion is not a water-in-oil (W/O) drilling fluid, it is, however, a system in which the bound water droplets are moderately dispersed into an oil phase. In addition, low temperature constant rheology can be achieved by adjusting the rheology of a low density oil based drilling fluid.
In a Pickering emulsion, the solid particle emulsifier is absorbed at the interface between oil and water, forming a stable interfacial film to prevent the coalescence of water droplets. This property can be used to improve the stability of oil based drilling fluids. However, in studies on the oil based drilling fluids based on Pickering emulsion, the interaction between a water droplet in the oil phase and an inorganic hydrophilic particle has been omitted; the effects of inorganic particles added to an oil based drilling fluid, such as calcium hydroxide, weighting agents and the drilled cuttings, on the existence of the water droplets in the emulsion are not considered. In laboratory study, calcium hydroxide, barite and kaolinite particles of different hydrating capacities were added into a W/O Pickering emulsion. Macro sedimentation experiment and microscope observation with microscopic images have proved that the water droplets are combined with the solid particles, existing in a form of bound water. This explains the aggregation of the solid particles. The bound water was characterized with laser confocal microscope and low temperature differential scanning calorimetry. The solid particles with bound water can be dispersed by treating the system with a dispersant, in this way the stability of the drilling fluid can be improved. An oil based drilling fluid based on W/O Pickering emulsion is not a water-in-oil (W/O) drilling fluid, it is, however, a system in which the bound water droplets are moderately dispersed into an oil phase. In addition, low temperature constant rheology can be achieved by adjusting the rheology of a low density oil based drilling fluid.
2023, 40(1): 35-40.
doi: 10.12358/j.issn.1001-5620.2023.01.004
Abstract:
To control the pollution of drilling fluids to the environment from the source and minimize the difficulty and cost of waste drilling fluid treatment, a compound filter loss reducer PLS has been developed through crosslinking modification of plant polyphenol (a biomass material), sodium lignosulfonate and corn starch. PLS is non-toxic and is easy to degrade, it has an EC50 of 7.78 × 104 mg/L, and BOD5/CODCr of 5.05%. Evaluation of PLS shows that a base mud treated with 2% PLS has API filtration rate of only 9.6 mL after hot rolling at 180 ℃ for 16 hours. PLS is better than carboxymethyl starch, CMC-LV and SAP (an amphoteric starch graft copolymer) in resisting salt and calcium contamination. An environmentally friendly water based drilling fluid was formulated with PLS as the only filter loss reducer and other environmentally friendly additives such as bonding lubricant, organo- and hydro-phobic nanometer plugging agent and bionic borehole wall strengthening agent. This drilling fluid was used to drill the horizontal mudstone section of an exploratory well in Dagang oilfield. The rheology, filtration property of the drilling fluid during drilling were very stable, the mud cake had low friction coefficient and was thin and tough. The drilling operation was successful with no downhole troubles encountered throughout the horizontal section.
To control the pollution of drilling fluids to the environment from the source and minimize the difficulty and cost of waste drilling fluid treatment, a compound filter loss reducer PLS has been developed through crosslinking modification of plant polyphenol (a biomass material), sodium lignosulfonate and corn starch. PLS is non-toxic and is easy to degrade, it has an EC50 of 7.78 × 104 mg/L, and BOD5/CODCr of 5.05%. Evaluation of PLS shows that a base mud treated with 2% PLS has API filtration rate of only 9.6 mL after hot rolling at 180 ℃ for 16 hours. PLS is better than carboxymethyl starch, CMC-LV and SAP (an amphoteric starch graft copolymer) in resisting salt and calcium contamination. An environmentally friendly water based drilling fluid was formulated with PLS as the only filter loss reducer and other environmentally friendly additives such as bonding lubricant, organo- and hydro-phobic nanometer plugging agent and bionic borehole wall strengthening agent. This drilling fluid was used to drill the horizontal mudstone section of an exploratory well in Dagang oilfield. The rheology, filtration property of the drilling fluid during drilling were very stable, the mud cake had low friction coefficient and was thin and tough. The drilling operation was successful with no downhole troubles encountered throughout the horizontal section.
2023, 40(1): 41-46.
doi: 10.12358/j.issn.1001-5620.2023.01.005
Abstract:
In view of the fact that the marine carbonate formation in Yuanba area is often polluted by acid radical and hydrogen sulfide, which causes the viscosity and water loss of drilling fluid to rise, the temperature resistance to decline, and the flow pattern to be difficult to control, bringing great challenges to on-site maintenance. In this paper, a bio chemical method is proposed to modify lignin to develop an environment-friendly filtration reducer LDR of biomass synthetic resin with a cluster multi branch structure. The performance evaluation results show that the product has a temperature resistance of 200 ℃, a salt resistance of 25%, and a calcium resistance of 3,000 mg/L, showing a strong temperature and salt resistance performance. With this as the core of the high temperature resistant material, a high temperature resistant composite brine drilling fluid system is constructed by introducing potassium, calcium, and sodium plasma. Two wells were applied in Yuanba area. The field application shows that the maximum density of drilling fluid in Yuanba X-701 well is 2.34 g/cm3, the electric measurement shows that the temperature is 157 ℃, and the acid radical content is 21,157 mg/L. The system still has good rheological property and strong anti pollution ability. The two electric measurements successfully reached the bottom at one time, and the drilling fluid viscosity returned for 48 s after 7 consecutive days of standstill. It only took 28.88 days to complete the sidetracking task. The successful application of this system indicates that biomass resources have made a new breakthrough in high-temperature and high-density drilling fluid, effectively meeting the requirements of high-temperature slim hole for drilling fluid, and has good guidance and reference significance for deep wells and ultra deep wells in Yuanba area.
In view of the fact that the marine carbonate formation in Yuanba area is often polluted by acid radical and hydrogen sulfide, which causes the viscosity and water loss of drilling fluid to rise, the temperature resistance to decline, and the flow pattern to be difficult to control, bringing great challenges to on-site maintenance. In this paper, a bio chemical method is proposed to modify lignin to develop an environment-friendly filtration reducer LDR of biomass synthetic resin with a cluster multi branch structure. The performance evaluation results show that the product has a temperature resistance of 200 ℃, a salt resistance of 25%, and a calcium resistance of 3,000 mg/L, showing a strong temperature and salt resistance performance. With this as the core of the high temperature resistant material, a high temperature resistant composite brine drilling fluid system is constructed by introducing potassium, calcium, and sodium plasma. Two wells were applied in Yuanba area. The field application shows that the maximum density of drilling fluid in Yuanba X-701 well is 2.34 g/cm3, the electric measurement shows that the temperature is 157 ℃, and the acid radical content is 21,157 mg/L. The system still has good rheological property and strong anti pollution ability. The two electric measurements successfully reached the bottom at one time, and the drilling fluid viscosity returned for 48 s after 7 consecutive days of standstill. It only took 28.88 days to complete the sidetracking task. The successful application of this system indicates that biomass resources have made a new breakthrough in high-temperature and high-density drilling fluid, effectively meeting the requirements of high-temperature slim hole for drilling fluid, and has good guidance and reference significance for deep wells and ultra deep wells in Yuanba area.
2023, 40(1): 47-53.
doi: 10.12358/j.issn.1001-5620.2023.01.006
Abstract:
Excessive development of pore fractures in the formation during drilling operations can lead to lost circulation and can easily result in safety incidents. In this research, a self-healing hydrogel based on cation-π, electrostatic, hydrogen bonding was prepared by a free radical polymerisation method for formation plugging, forming a dense sealing layer to contain lost circulation and prevent recurrence. Excellent self-healing properties in harsh conditions, with a self-healing efficiency of 70%, and can effectively seal the pores of 180 D sand discs with a sealing rate of nearly 90%. It also shows good sealing ability for other consolidated sand discs (permeability 2 D, 5 D, 20 D) and unconsolidated sand beds (20-40 mesh, 40-60 mesh, 60-80 mesh). Compared to conventional materials, the hydrogel can be self-healing by reducing the operating pressure drop to achieve an efficient seal. The self-repairing hydrogel can effectively improve the denseness of the sealing layers through secondary reduction of the permeability of the sealing layer, which improves the high temperature stability of the hydrogel and still has good sealing ability after high temperature aging. The hydrogel particles are well dispersed in the salt water and maintain stable rheological properties after hot rolling, which is beneficial for drilling fluid circulation. This study shows the potential of self-healing materials as plugging materials in the oil drilling industry.
Excessive development of pore fractures in the formation during drilling operations can lead to lost circulation and can easily result in safety incidents. In this research, a self-healing hydrogel based on cation-π, electrostatic, hydrogen bonding was prepared by a free radical polymerisation method for formation plugging, forming a dense sealing layer to contain lost circulation and prevent recurrence. Excellent self-healing properties in harsh conditions, with a self-healing efficiency of 70%, and can effectively seal the pores of 180 D sand discs with a sealing rate of nearly 90%. It also shows good sealing ability for other consolidated sand discs (permeability 2 D, 5 D, 20 D) and unconsolidated sand beds (20-40 mesh, 40-60 mesh, 60-80 mesh). Compared to conventional materials, the hydrogel can be self-healing by reducing the operating pressure drop to achieve an efficient seal. The self-repairing hydrogel can effectively improve the denseness of the sealing layers through secondary reduction of the permeability of the sealing layer, which improves the high temperature stability of the hydrogel and still has good sealing ability after high temperature aging. The hydrogel particles are well dispersed in the salt water and maintain stable rheological properties after hot rolling, which is beneficial for drilling fluid circulation. This study shows the potential of self-healing materials as plugging materials in the oil drilling industry.
2023, 40(1): 54-59.
doi: 10.12358/j.issn.1001-5620.2023.01.007
Abstract:
As a common technology for the prevention and control of lost circulation in low pressure bearing formations, the theoretical system and plugging materials have made great progress, but the important construction parameters have not been paid enough attention. Therefore, according to the underground in-situ stress environment, this paper selects high-strength plugging materials, and establishes the pressure plugging experimental scheme with different construction parameters and plugging materials while drilling.The self-developed large-scale true triaxial pressure plugging experimental equipment is used to conduct the test on the dense sandstone sample (size: 300 mm×297 mm×297 mm), and the hydraulic-fracture propagation law was observed. Based on the hydraulic-fracture, the pressure plugging experiment was carried out.According to the experimental results, for the formation with weak bearing capacity, the construction parameters will cause the pressure change in the well, thus affecting the plugging effect; repeated plugging operations in the same formation will cause fracture expansion and reduce the plugging effect; the sequence of plugging slurry entering the fracture and the structure of the plugging layer are closely related to the geometric parameters of the fracture. The regular knowledge obtained in this paper can provide some reference for the formulation of pressure plugging scheme.
As a common technology for the prevention and control of lost circulation in low pressure bearing formations, the theoretical system and plugging materials have made great progress, but the important construction parameters have not been paid enough attention. Therefore, according to the underground in-situ stress environment, this paper selects high-strength plugging materials, and establishes the pressure plugging experimental scheme with different construction parameters and plugging materials while drilling.The self-developed large-scale true triaxial pressure plugging experimental equipment is used to conduct the test on the dense sandstone sample (size: 300 mm×297 mm×297 mm), and the hydraulic-fracture propagation law was observed. Based on the hydraulic-fracture, the pressure plugging experiment was carried out.According to the experimental results, for the formation with weak bearing capacity, the construction parameters will cause the pressure change in the well, thus affecting the plugging effect; repeated plugging operations in the same formation will cause fracture expansion and reduce the plugging effect; the sequence of plugging slurry entering the fracture and the structure of the plugging layer are closely related to the geometric parameters of the fracture. The regular knowledge obtained in this paper can provide some reference for the formulation of pressure plugging scheme.
2023, 40(1): 60-66.
doi: 10.12358/j.issn.1001-5620.2023.01.008
Abstract:
This paper discusses the experimental studies on the compatibility of drilling fluid lubricants with screw rubbers at high temperature and deep well conditions. At different temperatures and additive concentrations, eight kinds of rubbers were tested for rates of volume increment, rates of mass increment and changes in tensional strength when they were in contact with drilling fluid additives, and the test results were compared and evaluated. The experimental results show that the rubber sample has big changes in drilling fluids treated with the lubricants R-1 and R-3; in the drilling fluid treated with R-1, the rates of volume increment of the rubbers were distributed between 56% and 175%, while in the drilling fluid treated with R-3, the rates of volume increment were distributed between 49% and 148%. When the concentrations of the lubricants were increased, the rates of volume and mass increments of the two rubbers are all increased, and the rubbers swell at higher rates. These results indicate that the raw oil of a lubricant is the key factor affecting the swelling of rubber. Using GC-MS technology, the raw oils were analyzed, and it was found that a lubricant whose raw oil has high content of aromatics has relatively large influence on the swelling of the rubbers. Based on the application properties of the lubricants, some lubricants suitable for use in high temperature deep well drilling were selected. The selected lubricants were used to replace those lubricants with high contents of unsaturated hydrocarbons in the third interval and the reservoir section of the wells drilled in the Taipen block, and rubber disintegration from the screw was significantly reduced. Statistic data showed that times of rubber disintegration was reduced from 11 well times/month in the past to 0.5 well times/month, and this greatly reduced the number of times of tripping and improved the productive efficiency.
This paper discusses the experimental studies on the compatibility of drilling fluid lubricants with screw rubbers at high temperature and deep well conditions. At different temperatures and additive concentrations, eight kinds of rubbers were tested for rates of volume increment, rates of mass increment and changes in tensional strength when they were in contact with drilling fluid additives, and the test results were compared and evaluated. The experimental results show that the rubber sample has big changes in drilling fluids treated with the lubricants R-1 and R-3; in the drilling fluid treated with R-1, the rates of volume increment of the rubbers were distributed between 56% and 175%, while in the drilling fluid treated with R-3, the rates of volume increment were distributed between 49% and 148%. When the concentrations of the lubricants were increased, the rates of volume and mass increments of the two rubbers are all increased, and the rubbers swell at higher rates. These results indicate that the raw oil of a lubricant is the key factor affecting the swelling of rubber. Using GC-MS technology, the raw oils were analyzed, and it was found that a lubricant whose raw oil has high content of aromatics has relatively large influence on the swelling of the rubbers. Based on the application properties of the lubricants, some lubricants suitable for use in high temperature deep well drilling were selected. The selected lubricants were used to replace those lubricants with high contents of unsaturated hydrocarbons in the third interval and the reservoir section of the wells drilled in the Taipen block, and rubber disintegration from the screw was significantly reduced. Statistic data showed that times of rubber disintegration was reduced from 11 well times/month in the past to 0.5 well times/month, and this greatly reduced the number of times of tripping and improved the productive efficiency.
2023, 40(1): 67-72.
doi: 10.12358/j.issn.1001-5620.2023.01.009
Abstract:
The Ledong block, a typical high temperature high pressure offshore block, is located in the depression slope zone of the Yinggehai Basin. Some formations drilled in this block have narrow safe drilling windows and mud losses in deep hole occurred frequently during drilling. To deal with the mud losses, the drilling data was studied and the mechanisms and nature of the mud losses were analyzed. Using the viscous element method, the change of the stresses around the borehole before and after borehole wall strengthening was simulated, and the opening of the prefilled fractures predicted. Using a new experiment apparatus which can simulate the plugging of variable fractures, a study was conducted on the particle size distribution and concentration optimization for borehole wall strengthening. The experimental results show that the D50 criterion is a better particle size matching criterion, and a reasonable concentration of the particles is 5%. A drilling fluid that is suitable for use in the Ledong block and has the ability of borehole wall strengthening is developed through optimization experiment. In a comprehensive evaluation experiment, the additives for borehole wall strengthening showed little effects on the rheology of the drilling fluid. Sand bed test showed that the depth of the filtrate invasion was only 1.5 cm. Dynamic pressure bearing capacity of 1mm fractures tested with the drilling fluid can be as high as 12 MPa.
The Ledong block, a typical high temperature high pressure offshore block, is located in the depression slope zone of the Yinggehai Basin. Some formations drilled in this block have narrow safe drilling windows and mud losses in deep hole occurred frequently during drilling. To deal with the mud losses, the drilling data was studied and the mechanisms and nature of the mud losses were analyzed. Using the viscous element method, the change of the stresses around the borehole before and after borehole wall strengthening was simulated, and the opening of the prefilled fractures predicted. Using a new experiment apparatus which can simulate the plugging of variable fractures, a study was conducted on the particle size distribution and concentration optimization for borehole wall strengthening. The experimental results show that the D50 criterion is a better particle size matching criterion, and a reasonable concentration of the particles is 5%. A drilling fluid that is suitable for use in the Ledong block and has the ability of borehole wall strengthening is developed through optimization experiment. In a comprehensive evaluation experiment, the additives for borehole wall strengthening showed little effects on the rheology of the drilling fluid. Sand bed test showed that the depth of the filtrate invasion was only 1.5 cm. Dynamic pressure bearing capacity of 1mm fractures tested with the drilling fluid can be as high as 12 MPa.
2023, 40(1): 73-81.
doi: 10.12358/j.issn.1001-5620.2023.01.010
Abstract:
Two-interval horizontal well profile is used to develop the tight gas reservoirs in the Sulige gas field. Downhole problems such as coexistence of borehole wall collapse and mud losses, high friction and poor hole cleaning have long remained difficulties during drilling operations. Based on the analyses of the geological characteristics and the collapse mechanisms of shale formations, a model for friction and torque calculation is developed. The changes of friction and torque between different well profiles are compared. A new drilling fluid with good plugging capacity and lubricity was developed with a nanophase emulsion, plugging agents o hard and soft particles, compound lubricants and high efficiency gel strength additives which were all selected through laboratory experiment. This drilling fluid has been successfully applied in field operations. Laboratory study has shown that this drilling fluid has good inhibitive capacity and good plugging capacity, and it can extend the instability period of hard and brittle shales, thereby maintaining the borehole wall stable. This drilling fluid also has good rheology and lubricity, low sand content and solid content. In field application, the resistance to casing string running into the hole was controlled within 350 kN, the friction to drilling string running into the hole was reduced by 24.21%, the torque was reduced by 34.31%, the average drilling time was 29.04 d, the average ROP was 17.64 m/h, which was 36.5% higher than that in drilling three-interval horizontal wells. Time spent in reaming because of borehole collapse was reduced by 89.50%. This drilling fluid has provided a powerful technical support for promoting the application of two-interval horizontal drilling in developing the tight gas reservoirs in the Sulige gas field.
Two-interval horizontal well profile is used to develop the tight gas reservoirs in the Sulige gas field. Downhole problems such as coexistence of borehole wall collapse and mud losses, high friction and poor hole cleaning have long remained difficulties during drilling operations. Based on the analyses of the geological characteristics and the collapse mechanisms of shale formations, a model for friction and torque calculation is developed. The changes of friction and torque between different well profiles are compared. A new drilling fluid with good plugging capacity and lubricity was developed with a nanophase emulsion, plugging agents o hard and soft particles, compound lubricants and high efficiency gel strength additives which were all selected through laboratory experiment. This drilling fluid has been successfully applied in field operations. Laboratory study has shown that this drilling fluid has good inhibitive capacity and good plugging capacity, and it can extend the instability period of hard and brittle shales, thereby maintaining the borehole wall stable. This drilling fluid also has good rheology and lubricity, low sand content and solid content. In field application, the resistance to casing string running into the hole was controlled within 350 kN, the friction to drilling string running into the hole was reduced by 24.21%, the torque was reduced by 34.31%, the average drilling time was 29.04 d, the average ROP was 17.64 m/h, which was 36.5% higher than that in drilling three-interval horizontal wells. Time spent in reaming because of borehole collapse was reduced by 89.50%. This drilling fluid has provided a powerful technical support for promoting the application of two-interval horizontal drilling in developing the tight gas reservoirs in the Sulige gas field.
2016, 33(5): 1-8.
doi: 10.3969/j.issn.1001-5620.2016.05.001
摘要：
综述了国内外页岩气井井壁失稳机理、稳定井壁主要方法及水基钻井液技术研究与应用现状，讨论了当前中国页岩气井钻井液技术面临的主要技术难题，分析了美国页岩气井与中国主要页岩气产区井壁失稳机理的差异，指出了中国页岩气井水基钻井液技术研究存在的误区与不足，提出了中国页岩气井水基钻井液技术发展方向。
综述了国内外页岩气井井壁失稳机理、稳定井壁主要方法及水基钻井液技术研究与应用现状，讨论了当前中国页岩气井钻井液技术面临的主要技术难题，分析了美国页岩气井与中国主要页岩气产区井壁失稳机理的差异，指出了中国页岩气井水基钻井液技术研究存在的误区与不足，提出了中国页岩气井水基钻井液技术发展方向。
2016, 33(1): 6-10.
doi: 10.3969/j.issn.1001-5620.2016.01.002
摘要：
以妥尔油脂肪酸和马来酸酐为主要原料合成了一种油基钻井液抗高温主乳化剂HT-MUL,并确定了妥尔油脂肪酸单体的最佳酸值及马来酸酐单体的最优加量。对HT-MUL进行了单剂评价,结果表明HT-MUL的乳化能力良好,配制的油水比为60:40的油包水乳液的破乳电压最高可达490 V,90:10的乳液破乳电压最高可达1000 V。从抗温性、滤失性、乳化率方面对HT-MUL和国内外同类产品进行了对比,结果表明HT-MUL配制的乳液破乳电压更大、滤失量更小、乳化率更高,整体性能优于国内外同类产品。应用主乳化剂HT-MUL配制了高密度的油基钻井液,其性能评价表明体系的基本性能良好,在220℃高温热滚后、破乳电压高达800 V,滤失量低于5 mL。HT-MUL配制的油基钻井液具有良好的抗高温性和乳化稳定性。
以妥尔油脂肪酸和马来酸酐为主要原料合成了一种油基钻井液抗高温主乳化剂HT-MUL,并确定了妥尔油脂肪酸单体的最佳酸值及马来酸酐单体的最优加量。对HT-MUL进行了单剂评价,结果表明HT-MUL的乳化能力良好,配制的油水比为60:40的油包水乳液的破乳电压最高可达490 V,90:10的乳液破乳电压最高可达1000 V。从抗温性、滤失性、乳化率方面对HT-MUL和国内外同类产品进行了对比,结果表明HT-MUL配制的乳液破乳电压更大、滤失量更小、乳化率更高,整体性能优于国内外同类产品。应用主乳化剂HT-MUL配制了高密度的油基钻井液,其性能评价表明体系的基本性能良好,在220℃高温热滚后、破乳电压高达800 V,滤失量低于5 mL。HT-MUL配制的油基钻井液具有良好的抗高温性和乳化稳定性。
2016, 33(1): 33-36.
doi: 10.3969/j.issn.1001-5620.2016.01.007
摘要：
页岩具有极低的渗透率和极小的孔喉尺寸,传统封堵剂难以在页岩表面形成有效的泥饼,只有纳米级颗粒才能封堵页岩的孔喉,阻止液相侵入地层,维持井壁稳定,保护储层。以苯乙烯(St)、甲基丙烯酸甲酯(MMA)为单体,过硫酸钾(KPS)为引发剂,采用乳液聚合法制备了纳米聚合物微球封堵剂SD-seal。通过红外光谱、透射电镜、热重分析和激光粒度分析对产物进行了表征,通过龙马溪组岩样的压力传递实验研究了其封堵性能。结果表明,SD-seal纳米粒子分散性好,形状规则(基本为球形),粒度较均匀(20 nm左右),分解温度高达402.5℃,热稳定性好,阻缓压力传递效果显著,使龙马溪组页岩岩心渗透率降低95%。
页岩具有极低的渗透率和极小的孔喉尺寸,传统封堵剂难以在页岩表面形成有效的泥饼,只有纳米级颗粒才能封堵页岩的孔喉,阻止液相侵入地层,维持井壁稳定,保护储层。以苯乙烯(St)、甲基丙烯酸甲酯(MMA)为单体,过硫酸钾(KPS)为引发剂,采用乳液聚合法制备了纳米聚合物微球封堵剂SD-seal。通过红外光谱、透射电镜、热重分析和激光粒度分析对产物进行了表征,通过龙马溪组岩样的压力传递实验研究了其封堵性能。结果表明,SD-seal纳米粒子分散性好,形状规则(基本为球形),粒度较均匀(20 nm左右),分解温度高达402.5℃,热稳定性好,阻缓压力传递效果显著,使龙马溪组页岩岩心渗透率降低95%。
2016, 33(1): 17-21.
doi: 10.3969/j.issn.1001-5620.2016.01.004
摘要：
目前中国页岩气水平井定向段及水平段钻井均使用油基钻井液,但油基岩屑处理费用昂贵,急需开发和应用一种具有环境保护特性的高性能水基钻井液体系。介绍了2种高性能水基钻井液体系的室内实验和现场试验效果。在长宁H9-4井水平段、长宁H9-3和长宁H9-5井定向至完井段试验了GOF高性能水基钻井液体系,该体系采用的是聚合物封堵抑制方案,完全采用水基润滑方式;在昭通区块YS108H4-2井水平段试验了高润强抑制性水基钻井液体系,该体系采用的是有机、无机盐复合防膨方案以及润滑剂与柴油复合润滑方式。现场应用表明,定向段机械钻速提高50%~75%,水平段机械钻速提高75%~100%。通过实验数据及现场使用情况,对比分析了2种体系的优劣,找出了他们各自存在的问题,并提出了改进的思路,为高性能水基钻井液的进一步完善提供一些经验。
目前中国页岩气水平井定向段及水平段钻井均使用油基钻井液,但油基岩屑处理费用昂贵,急需开发和应用一种具有环境保护特性的高性能水基钻井液体系。介绍了2种高性能水基钻井液体系的室内实验和现场试验效果。在长宁H9-4井水平段、长宁H9-3和长宁H9-5井定向至完井段试验了GOF高性能水基钻井液体系,该体系采用的是聚合物封堵抑制方案,完全采用水基润滑方式;在昭通区块YS108H4-2井水平段试验了高润强抑制性水基钻井液体系,该体系采用的是有机、无机盐复合防膨方案以及润滑剂与柴油复合润滑方式。现场应用表明,定向段机械钻速提高50%~75%,水平段机械钻速提高75%~100%。通过实验数据及现场使用情况,对比分析了2种体系的优劣,找出了他们各自存在的问题,并提出了改进的思路,为高性能水基钻井液的进一步完善提供一些经验。
2016, 33(4): 74-78.
doi: 10.3969/j.issn.1001-5620.2016.04.015
摘要：
利用自主研发的水泥环密封性实验装置研究了套管内加卸压循环作用下水泥环的密封性，根据实验结果得出了循环应力作用下水泥环密封性失效的机理。实验结果显示，在较低套管内压循环作用下，水泥环保持密封性所能承受的应力循环次数较多；在较高循环应力作用下，水泥环密封性失效时循环次数较少。表明在套管内较低压力作用下，水泥环所受的应力较低，应力水平处于弹性状态，在加卸载的循环作用下，水泥环可随之弹性变形和弹性恢复；在较高应力作用下，水泥环内部固有的微裂纹和缺陷逐渐扩展和连通，除了发生弹性变形还产生了塑性变形；随着应力循环次数的增加，塑性变形也不断地累积。循环压力卸载时，套管弹性回缩而水泥环塑性变形不可完全恢复，2者在界面处的变形不协调而引起拉应力。当拉应力超过界面处的胶结强度时出现微环隙，导致水泥环密封性失效，水泥环发生循环应力作用的低周期密封性疲劳破坏。套管内压力越大，水泥环中产生的应力水平越高，产生的塑性变形越大，每次卸载时产生的残余应变和界面处拉应力也越大，因此引起密封性失效的应力循环次数越少。
利用自主研发的水泥环密封性实验装置研究了套管内加卸压循环作用下水泥环的密封性，根据实验结果得出了循环应力作用下水泥环密封性失效的机理。实验结果显示，在较低套管内压循环作用下，水泥环保持密封性所能承受的应力循环次数较多；在较高循环应力作用下，水泥环密封性失效时循环次数较少。表明在套管内较低压力作用下，水泥环所受的应力较低，应力水平处于弹性状态，在加卸载的循环作用下，水泥环可随之弹性变形和弹性恢复；在较高应力作用下，水泥环内部固有的微裂纹和缺陷逐渐扩展和连通，除了发生弹性变形还产生了塑性变形；随着应力循环次数的增加，塑性变形也不断地累积。循环压力卸载时，套管弹性回缩而水泥环塑性变形不可完全恢复，2者在界面处的变形不协调而引起拉应力。当拉应力超过界面处的胶结强度时出现微环隙，导致水泥环密封性失效，水泥环发生循环应力作用的低周期密封性疲劳破坏。套管内压力越大，水泥环中产生的应力水平越高，产生的塑性变形越大，每次卸载时产生的残余应变和界面处拉应力也越大，因此引起密封性失效的应力循环次数越少。
2017, 34(1): 1-8.
doi: 10.3969/j.issn.1001-5620.2017.01.001
摘要：
分析了硬脆性泥页岩井壁失稳的原因，介绍了纳米材料特点及其应用，并概述了国内外钻井液用纳米封堵剂的研究进展，包括有机纳米封堵剂、无机纳米封堵剂、有机/无机纳米封堵剂，以及纳米封堵剂现场应用案例。笔者认为：利用无机纳米材料刚性特征以及有机聚合物可任意变形、支化成膜等特性，形成的一种核壳结构的无机/聚合物类纳米封堵剂，能够很好地分散到钻井液中，且对钻井液黏度和切力影响较小，这种类型的纳米封堵剂能够在低浓度下封堵泥页岩孔喉，建立一种疏水型且具有一定强度的泥页岩人工井壁，这不仅能够阻止钻井液侵入，而且还能提高地层承压能力，无机纳米材料与有机聚合物的结合是未来钻井液防塌剂的发展方向。
分析了硬脆性泥页岩井壁失稳的原因，介绍了纳米材料特点及其应用，并概述了国内外钻井液用纳米封堵剂的研究进展，包括有机纳米封堵剂、无机纳米封堵剂、有机/无机纳米封堵剂，以及纳米封堵剂现场应用案例。笔者认为：利用无机纳米材料刚性特征以及有机聚合物可任意变形、支化成膜等特性，形成的一种核壳结构的无机/聚合物类纳米封堵剂，能够很好地分散到钻井液中，且对钻井液黏度和切力影响较小，这种类型的纳米封堵剂能够在低浓度下封堵泥页岩孔喉，建立一种疏水型且具有一定强度的泥页岩人工井壁，这不仅能够阻止钻井液侵入，而且还能提高地层承压能力，无机纳米材料与有机聚合物的结合是未来钻井液防塌剂的发展方向。
2018, 35(2): 1-16.
doi: 10.3969/j.issn.1001-5620.2018.02.001
摘要：
通常在勘探开发油气过程中会发生不同程度的油气层损害，导致产量下降、甚至"枪毙"油气层等，钻井液是第一个与油气层相接触的外来流体，引起的油气层损害程度往往较大。为减轻或避免钻井液导致的油气层损害、提高单井产量，国内外学者们进行了长达半个世纪以上的研究工作，先后建立了"屏蔽暂堵、精细暂堵、物理化学膜暂堵"三代暂堵型保护油气层钻井液技术，使保护油气层效果逐步提高，经济效益明显。但是，与石油工程师们追求的"超低"损害目标仍存在一定差距，特别是随着非常规、复杂、超深层、超深水等类型油气层勘探开发力度的加大，以前的保护技术难以满足要求。为此，将仿生学引入保护油气层钻井液理论中，发展了适合不同油气层渗透率大小的"超双疏、生物膜、协同增效"仿生技术，并在各大油田得到推广应用，达到了"超低"损害目标，标志着第四代暂堵型保护油气层钻井液技术的建立。对上述4代暂堵型保护油气层技术的理论基础、实施方案、室内评价、现场应用效果与优缺点等进行了论述，并通过梳理阐明了将来的研究方向与发展趋势，对现场技术人员和科技工作者具有较大指导意义。
通常在勘探开发油气过程中会发生不同程度的油气层损害，导致产量下降、甚至"枪毙"油气层等，钻井液是第一个与油气层相接触的外来流体，引起的油气层损害程度往往较大。为减轻或避免钻井液导致的油气层损害、提高单井产量，国内外学者们进行了长达半个世纪以上的研究工作，先后建立了"屏蔽暂堵、精细暂堵、物理化学膜暂堵"三代暂堵型保护油气层钻井液技术，使保护油气层效果逐步提高，经济效益明显。但是，与石油工程师们追求的"超低"损害目标仍存在一定差距，特别是随着非常规、复杂、超深层、超深水等类型油气层勘探开发力度的加大，以前的保护技术难以满足要求。为此，将仿生学引入保护油气层钻井液理论中，发展了适合不同油气层渗透率大小的"超双疏、生物膜、协同增效"仿生技术，并在各大油田得到推广应用，达到了"超低"损害目标，标志着第四代暂堵型保护油气层钻井液技术的建立。对上述4代暂堵型保护油气层技术的理论基础、实施方案、室内评价、现场应用效果与优缺点等进行了论述，并通过梳理阐明了将来的研究方向与发展趋势，对现场技术人员和科技工作者具有较大指导意义。
2016, 33(6): 121-126.
doi: 10.3969/j.issn.1001-5620.2016.06.022
摘要：
统计长庆油田罗*区块2015年存地液量与油井一年累积产量的关系发现，存地液量越大，一年累积产量越高，与常规的返排率越高产量越高概念恰恰相反，可能与存地液的自发渗吸替油有关。核磁实验结果表明，渗吸替油不同于驱替作用，渗吸过程中小孔隙对采出程度贡献大，而驱替过程中大孔隙对采出程度贡献大，但从现场致密储层岩心孔隙度来看，储层驱替效果明显弱于渗吸效果。通过实验研究了影响自发渗吸效率因素，探索影响压裂液油水置换的关键影响因素，得出了最佳渗吸采出率及最大渗吸速度现场参数。结果表明，各参数对渗吸速度的影响顺序为：界面张力 > 渗透率 > 原油黏度 > 矿化度,岩心渗透率越大，渗吸采收率越大，但是增幅逐渐减小；原油黏度越小，渗吸采收率越大；渗吸液矿化度越大，渗吸采收率越大；当渗吸液中助排剂浓度在0.005%~5%，即界面张力在0.316~10.815 mN/m范围内时，浓度为0.5%（界面张力为0.869 mN/m）的渗吸液可以使渗吸采收率达到最大。静态渗吸结果表明：并不是界面张力越低，采收率越高，而是存在某一最佳界面张力，使地层中被绕流油的数量减少，渗吸采收率达到最高，为油田提高致密储层采收率提供实验指导。
统计长庆油田罗*区块2015年存地液量与油井一年累积产量的关系发现，存地液量越大，一年累积产量越高，与常规的返排率越高产量越高概念恰恰相反，可能与存地液的自发渗吸替油有关。核磁实验结果表明，渗吸替油不同于驱替作用，渗吸过程中小孔隙对采出程度贡献大，而驱替过程中大孔隙对采出程度贡献大，但从现场致密储层岩心孔隙度来看，储层驱替效果明显弱于渗吸效果。通过实验研究了影响自发渗吸效率因素，探索影响压裂液油水置换的关键影响因素，得出了最佳渗吸采出率及最大渗吸速度现场参数。结果表明，各参数对渗吸速度的影响顺序为：界面张力 > 渗透率 > 原油黏度 > 矿化度,岩心渗透率越大，渗吸采收率越大，但是增幅逐渐减小；原油黏度越小，渗吸采收率越大；渗吸液矿化度越大，渗吸采收率越大；当渗吸液中助排剂浓度在0.005%~5%，即界面张力在0.316~10.815 mN/m范围内时，浓度为0.5%（界面张力为0.869 mN/m）的渗吸液可以使渗吸采收率达到最大。静态渗吸结果表明：并不是界面张力越低，采收率越高，而是存在某一最佳界面张力，使地层中被绕流油的数量减少，渗吸采收率达到最高，为油田提高致密储层采收率提供实验指导。
2017, 34(3): 21-26.
doi: 10.3969/j.issn.1001-5620.2017.03.004
摘要：
目前长水平井段井壁失稳问题仍是制约国内外页岩气资源钻探开发的重大工程技术难题。为解决龙马溪组页岩长水平井段的井壁失稳问题，采用X射线衍射分析、氦气孔隙体积测试、高压压汞测试、高分辨率场发射扫描电镜、CT扫描、岩石连续刻划强度等实验，分析了龙马溪组页岩微观组构特征及理化特性，探讨了微观组构特征、理化特性对龙马溪组页岩井壁稳定的影响。研究表明：龙马溪页岩富含脆性矿物，黏土矿物以伊蒙混层为主，微纳米孔隙发育，微裂隙呈缝状、近平行分布，敏感性矿物的存在及其层理、微裂缝发育是导致页岩井壁失稳的主要内在因素。为此，针对性地提出了多元协同稳定井壁水基钻井液防塌技术对策，即"强化封堵-适度抑制-合理密度-高效润滑"。应用该技术对策构建了高性能水基钻井液优化配方，评价表明，该体系有较好的封堵性和抑制裂缝扩展的能力。该体系在黄金坝区块2口井三开进行了现场试验。现场试验结果表明，该体系较好地解决了页岩长水平井段的井壁失稳和水平段摩阻较大的问题，为中国采用水基钻井液技术高效钻探开发页岩气资源提供了新的思路及经验。
目前长水平井段井壁失稳问题仍是制约国内外页岩气资源钻探开发的重大工程技术难题。为解决龙马溪组页岩长水平井段的井壁失稳问题，采用X射线衍射分析、氦气孔隙体积测试、高压压汞测试、高分辨率场发射扫描电镜、CT扫描、岩石连续刻划强度等实验，分析了龙马溪组页岩微观组构特征及理化特性，探讨了微观组构特征、理化特性对龙马溪组页岩井壁稳定的影响。研究表明：龙马溪页岩富含脆性矿物，黏土矿物以伊蒙混层为主，微纳米孔隙发育，微裂隙呈缝状、近平行分布，敏感性矿物的存在及其层理、微裂缝发育是导致页岩井壁失稳的主要内在因素。为此，针对性地提出了多元协同稳定井壁水基钻井液防塌技术对策，即"强化封堵-适度抑制-合理密度-高效润滑"。应用该技术对策构建了高性能水基钻井液优化配方，评价表明，该体系有较好的封堵性和抑制裂缝扩展的能力。该体系在黄金坝区块2口井三开进行了现场试验。现场试验结果表明，该体系较好地解决了页岩长水平井段的井壁失稳和水平段摩阻较大的问题，为中国采用水基钻井液技术高效钻探开发页岩气资源提供了新的思路及经验。
2016, 33(3): 67-72.
doi: 10.3969/j.issn.1001-5620.2016.03.014
摘要：
针对顺南区块超深高温高压气井固井面临井底温度高、气层活跃难压稳的问题，研究了胶乳纳米液硅高温防气窜水泥体系。通过将纳米液硅防气窜剂与胶乳防气窜剂复配使用，协同增强水泥浆防气窜性能；不同粒径硅粉复配与加量优化，增强水泥石高温稳定性；无机纤维桥联阻裂堵漏，抑制裂缝延展，提高水泥浆防漏性能和水泥石抗冲击性能。该水泥浆体系具有流动性好、API失水量小于50 mL、直角稠化、SPN值小于1，水泥石具有高温强度稳定性好、胶结强度高、抗冲击能力强的特点。密度为1.92 g/cm3的水泥浆体系在190℃、21 MPa养护30 h后超声波强度逐渐平稳，一界面胶结强度达12.6 MPa；水泥石弹性模量较常规低失水水泥石降低52%，抗冲击强度增加了188%，且受霍普金森杆冲击后仅纵向出现几条未贯穿的裂纹。该高温防气窜水泥浆体系在顺南5-2井和顺南6井成功应用，较好地解决了顺南区块超深气井固井难题。
针对顺南区块超深高温高压气井固井面临井底温度高、气层活跃难压稳的问题，研究了胶乳纳米液硅高温防气窜水泥体系。通过将纳米液硅防气窜剂与胶乳防气窜剂复配使用，协同增强水泥浆防气窜性能；不同粒径硅粉复配与加量优化，增强水泥石高温稳定性；无机纤维桥联阻裂堵漏，抑制裂缝延展，提高水泥浆防漏性能和水泥石抗冲击性能。该水泥浆体系具有流动性好、API失水量小于50 mL、直角稠化、SPN值小于1，水泥石具有高温强度稳定性好、胶结强度高、抗冲击能力强的特点。密度为1.92 g/cm3的水泥浆体系在190℃、21 MPa养护30 h后超声波强度逐渐平稳，一界面胶结强度达12.6 MPa；水泥石弹性模量较常规低失水水泥石降低52%，抗冲击强度增加了188%，且受霍普金森杆冲击后仅纵向出现几条未贯穿的裂纹。该高温防气窜水泥浆体系在顺南5-2井和顺南6井成功应用，较好地解决了顺南区块超深气井固井难题。
2020, 37(6): 685-693.
doi: 10.3969/j.issn.1001-5620.2020.06.002
Abstract:
2016, 33(6): 1-9.
doi: 10.3969/j.issn.1001-5620.2016.06.001
Abstract:
2016, 33(6): 45-50.
doi: 10.3969/j.issn.1001-5620.2016.06.008
Abstract:
2017, 34(1): 1-8.
doi: 10.3969/j.issn.1001-5620.2017.01.001
Abstract:
2017, 34(1): 16-22.
doi: 10.3969/j.issn.1001-5620.2017.01.003
Abstract:
2018, 35(1): 101-104.
doi: 10.3969/j.issn.1001-5620.2018.01.019
Abstract:
2016, 33(6): 10-16.
doi: 10.3969/j.issn.1001-5620.2016.06.002
Abstract:
2018, 35(1): 34-37.
doi: 10.3969/j.issn.1001-5620.2018.01.006
Abstract:
2018, 35(1): 71-76.
doi: 10.3969/j.issn.1001-5620.2018.01.014
Abstract:
Competent Authorities：China National Petroleum Corporation Ltd
Sponsored by：CNPC Bohai Drilling Engineering Co. LtdPetroChina Huabei Oilfield Company
Editor-in-Chief：Shi-chun Chen
Address： Editorial Department of Drilling Fluid and Completion Fluid, Bohai Drilling Engineering Institute, Yanshan South Road, Renqiu City, Hebei Province
Postcode： 062552
Tel：（0317）2725487 2722354
E-mail： zjyywjy@126.com
CN13-1118/TE
ISSN1001-5620
