A New Chapter For Scientific Research In Oil Well Cementing Engineering

The Geopolitical Control And Market Competition For The Special Strategic Resource - Oil In International Energy Field Have No Longer Confined To Pure Business Scope Nowadays. The Oil Resource Has Not Only Become The Weapon For Political And Economic And Military Struggle In World's Great Powers, But Also Deeply Affects National Security And International Political Structure. Although The Energy Diversification Has Already Been Inevitable From The Points Of National Economic And Social Coordinated Development And Atmospheric Environment Control, The Oil Is Still An Important Energy For World Economic Development. To Increase Oil Production, It Is Essential To Improve The Cementing Technology. Well Cementing Is One Of Important Steps During The Construction Of Oil And Gas Wells. It Is A One-Off Underground Downhole Operation Involving Wide Technologies, High Construction Risks And High Technical Requirements. In Addition, The Operation Quality Is Difficult To Be Guaranteed. The Cementing Operation Relates To The Successful Completion Of Oil And Gas Well. It Will Also Affect The Stimulation Efficiency Of The Oil And Gas Wells After Being Put Into Operation, Single Well Productivity, Production Life Of Oil And Gas Wells And Investment Benefits Of Oil And Gas Reservoir Development. The Fixed Cost For Cementing Works Also Takes Up A Large Proportion In The Drilling Works. Hundreds Of Thousands Of Gas And Oil Wells Have Been Drilled In China Since Liberation. More Than 1/3 Of Wells Are Operated With Faults Due To Poor Interlayer Separation. How Does The Oil Company Promote The Technical Progress, Improve The Overall Level And Solve The Production Problem Of Cementing Industry So As To Improve The International Competitiveness Of Cementing Industry In China? Now, We Will Learn More About The Case About Unsolved Historical Problems For Years About Dagang Oilfield, Which Have Been Solved Under The Joint Help Of Scientific Research Team Led By Professor Guo Xiaoyang And OMAX Oilfield Technology Co., Ltd.

Dagang Oilfield’s Dilemma: How To Solve Historical Problems

 Dagang Oilfield, Located In Binhai New Area Of Tianjin With Total Area Of Exploration And Development Of 18,716 Km2, Is An Oil And Gas Production Base Integrating Oil And Gas Exploration, Development, Processing Of Crude Oil, Machine Manufacturing, Research Design, Logistics Service, Diversifying Operation And Social Benefits. Many Oil-Industry Insiders Believe That Dagang Oilfield Has Stepped Into “Middle-Old Age” With Smaller Exploration And Development Potential After More Than 50 Years Of Development. With The Development History Of Over 50 Years, Dagang Oilfield Has Entered Into The Middle And Later Periods Of Development Of Mesozoic And Paleozoic Oil Deposit With Multiple Zone And High Oil-Gas Ratio, Difficult In Increasing And Stabilizing The Production. To Stabilize Current Productivity Scale And Further Tap Production Potentiality, The Oil Workers Mainly Adopt The Production Methods Such As Thickening Directional And Adjusting Wells, Slicing, Water-Flooding And Acid Fracturing Treatment. Thus, The Cementing Quality Mainly Based On The Interlayer Separation Has Crucial Safeguard Effects On Reasonably Using Reservoir Stratum, Ensuring Stimulation Efficiency, Improving Single Well Productivity And Implementation Effect Of Development Program. The 3rd Oil Production Plant Of Dagang Oilfield (Group) Co., Ltd. Has The Maximum Oil Production, Covering Seven Development Blocks Such As Duanliubo, Zaoyuan, Wangguantun, Xiaoji, Wumaying, Shenvsi And Yesanbo; The Productivity Construction Faces Challenges Due To More Sites With Wide Areas, Different Well Depths, Complex Directional Well Tracks, And Difficulties In Well Drilling And In Guaranteeing The Cementing Quality. Especially Duanliubo Block, Although The Production Potentiality For Extension And Infilling And Adjusting Wells Is Big After Fine Reservoir Description, The Deep Burial Depth And The Long Reservoir Well Interval, Under The Combined Influence Of Long-Term Water Flooding And Edge Water, Lead To Plural Pressures And Complex Oil-Water Relation. Thus, The Cementing Quality For The Adjusting Wells In This Block Remains At Lower Level For Years, Affecting The Accurate Positioning Of Oil And Water Layer And Perforation Height As Well As Modification Effects. The Production Capacity Of Oil Layer Cannot Be Fully Developed, Impeding The Secondary Development Of Old Oilfields In Technology. Wang Haibin, Deputy Director Of Project Management Department Of Productivity Of The 3rd Oil Production Plant, Has Been Working For Years With Several Scientific Research And Technology Services Organizations To Solve This Problem. They Tried Many Technical Solutions, But Failed To Solve The Technical Bottleneck. While Recognizing The Differences Between The Development Status And The Objective Conditions, Dagang Oilfield (Group) Co., Ltd. Sees Its Own Advantages And Believes That Big Development And Major Breakthrough On Exploration And Development Should Depend On Scientific And Technological Progress. Only The Technology Can Promote The Rapid Development Of Dagang Oilfield.

OMAX Helps To Overcome The Difficulties

 Deputy Director Wang Haibin Thinks That The Way To Solve These Problems Is To Find The Organizations With Scientific Research Strength And Practical Guidance Ability As Well As The Professionals. OMAX Oilfield Technology Co., Ltd. Comes Into Its Sight After The Investigation, Inquiring And Screening. OMAX Establishes “Production-Learning-Research Base” And “Practical Teaching Base” With Southwest Petroleum University, Forming Integrated “Production- Learning- Research” Science And Technology System. OMAX, Founded In 2004 , Has Set Up Branch Company In Shuangliu - Production And R&D Base, Northwest Project Management Department In Luntai Of Xinjiang, Southwest Project Management Departments In Langzhong And Fuling Of Sichuan And North China Project Management Department In Tianjin; OMAX Mainly Engages In The Development And Research Of The Petrol Engineering Technology, And The Research, Production And Marketing Of The Oilfield Chemicals And Provides Professional Engineering Technology Services On Site. Meanwhile, Xinjiang Debang Oilfield Technology Co., Ltd. Was Founded For Providing Drilling Fluid Materials And Technical Services. OMAX Repeatedly Implements “Research -  Application -  Re-Research” Process To Continuously Improve Cementing Technical Problems And Has Strong Technical Strengths In Researching, Developing, Producing And Applying The Cementing Materials; It Forms Outstanding Professional Characteristics And Technical Advantages Focusing On Cementing Technology For Solving Extra-Deep Well, Complicated Wells And Problem Wells; The Self-Developed Oil Well Cement Slurry System Has Been Widely Used In Several Hundred Well Times Of Cementing Operation For Major Oil And Gas Fields. Another Big Advantage Is To Have Rich Service Experience. OMAX Is One Of The Service Providers For Low-Density Cement Slurry To Sinopec Northwest Oilfield, Providing 40 Well-Times Of Low Density Technology Services And More Than 50 Well-Times Of High Temperature Deep Well Cementing Technology Services For Northwest Oilfield Each Year. In Addition, It Provides Cementing Technology Services For Target Zone Of 35 Wells Of 38  In Puguang Gas Field, More Than 15 Well-Times Of High Temperature Deep Well Cementing Technology Services For South Oil Exploration & Development Co., Ltd. Each Year, More Than 40 Well-Times Of Oil-Base Mud Cementing Technology Services For Tarim Oilfield Company Each Year And All The Cementing Technology Services For Target Zone And Partial Non-Target Zone Of Shale Gas Wells Of Shell (Sichuan) Petroleum Co., Ltd. Supported By Southwest Petroleum University, It Also Provides Cement Slurry Technology Services For Deep Wells And Complicated Wells. It Is The Supplier To CNPC And Sinopec And Long-Term Agreement Procurement Organization And Annual Service Contract Organization To Tarim Oilfield Company And Has Been Rated As “Excellent” Organization In Comprehensive Comparison In Long-Term Agreement Procurement Organizations. Professional Talent Reserve Is One Of The Competitive Advantages For Dagang Oilfield. The Technical Service Team Led By Zhang Jiaxing, Deputy General Manager And Technical Expert Of OMAX, Has Long Been Engaged In The Professional Engineering Technologies In The Development Of Oil Drilling, Cementing And Well Completion Engineering And Oil-Field Chemicals, System Design And Construction Operation. For The Cementing Quality Of Dagang Oilfield, He Visited The Working Site To Communicate And Discuss With The Staff In Oil Well Cementing Engineering And Conduct Related Experiments. Besides, He Proposed The Technical Scheme Of Elastic-Plastic Quick-Setting Anti-Channeling And Anti-Leakage Fiber Cement Slurry System With Early Strength. In The Early Stage Of The Project, The Staff Of OMAX And Dagang Oilfield Proposed The Scheme After The Investigation, Discussion And Negotiation. However, Everything Is Ready Except One Crucial Element. The Reasons Include: The Feasibility Of The Scheme Shall Be Inspected Through Cementing Engineering Test First In Order To Ensure Smooth Execution Of The Scheme. Dagang Oilfield Itself Has The Technical Problems Such As Long Open Interval, Complex Formation Lithology, Big Hole Deviation Angle And Disordered Pressure In Water-Flooding Position In The Old Block. Although The Early Trials Showed That The Cementing Quality Has Made A Certain Progress, It Failed To Achieve The Desired Results. It Is A Tricky Problem. In Addition, The Petrol Engineering Technology Itself Is A Concealed Underground Works With Fixed Operation Cost. In Addition To Technical Feasibility, It Shall Take The Economy Of Development Into Account. At This Difficult Time, The Experts Of OMAX Thought Of Guo Xiaoyang, Professor Of “State Key Laboratory Of Oil And Gas Reservoir Geology And Development Engineering” Of Southwest Petroleum University.

Trilateral Cooperation: Perfect Combination Of Theory And Practice

Southwest Petroleum University Is The Second Petroleum University Founded In The New China. Its Oil And Gas Engineering Discipline Is The National Level Key Discipline. Professor Guo, Teacher Of College Of Petroleum And Natural Gas Engineering Of Southwest Petroleum University, Is The Academic Backbone For Grade-2 National Key Discipline Construction Of Oil-Gas Well Engineering Of The University And State Key Laboratory Of Oil And Gas Reservoir Geology And Development Engineering, Member Of Chinese Petroleum Society And Society Of Petroleum Engineers, Expert Committee Of China's Oil And Gas Drilling Engineering Standardization Committee And Deputy Director Of Cementing Group Of Chinese Petroleum Society. Since His Teaching Career, He Directed And Completed Over 60 National, Provincial And Oilfield Cooperative Key Scientific And Technological Projects And Has Already Got 1 Second National Prize For Progress In Science And Technology And 6 Provincial Science And Technology Awards. He Is Good At Comprehensively Applying Multi-Disciplinary Theories Of Geology, Chemistry, Hydromechanics And Petroleum Engineering To Propose Highly Targeted Process Technology With Strong Creativity And Significant Application Effect By Taking The Basic Applied Theory And Mechanism Study As The Breakthrough Points. He Led The Research Group To Study The Cementing Technology Serially Against The Oil And Gas Resources In Ordos Basin Which Was Regarded By The International Authoritative Institutions As The World’s Most Difficult Exploitation Area With Typical Characteristics Of “Extra-Low Permeability”, “Ultra-Low Permeability” And “Low Grade”, To Form A Cementing Technology With High Toughness And Strong Plugging And Leakage Control For Effectively Assuring The Cementing Quality. The Excellence Rate Of Cementing Quality Reached 98.1%. Such Technology, Breaking The Foreign Technology Blockade And Solving The Technical Problems Of “Jamming, Collapse, Leakage And Damage To The Reservoir Stratum”, Became One Of The Exploration Theories And Key Technologies For Detecting Oil In Lower Yanchang Formation In The Central And Western Erdos Basin And Achieved Great Social And Economic Benefits. In 2013 , It Won Second National Prize For Progress In Science And Technology. After 20 Years Of Persistent Efforts, He Led His Group To Innovate And Develop Rheological Differential Theory On Laminar Flow, Multiple Displacement Theory And Scientific Structure Design Theory For Pad Fluid. He Developed Independently The Efficient Anti-Pollution Isolation Liquid System Centered On Anti-Pollution Isolating Agents GYW201  And GYW301 . The System Was The Preferred Cementing Technology For Deep Wells, Ultra-Deep Wells And Complicated Wells, Successfully Used In Sichuan And Tarim Oil And Gas Fields Successively And Effectively Ensuring The Efficient, Safe And Economic Development Of Main Gas Fields In China, With Direct Economic Benefits Of Several Hundred Million CNY. It Won Third Prize Of Science And Technology Progress Award In Sichuan And Third Prize Of Technology Approved By The China Petroleum And Chemical Industry Association In December  2013 . Tarim Oilfield Is The Source To Transport The Natural Gas From The West To The East In China, Characterized By Deep Embedded Depth Of Reservoir Stratum, Thick Overlying Rock And More Low Pressure Intervals. To Ensure Successful Well Drilling, The Multi-Layer Casing Well Structure Must Be Adopted, Leading To Large Drilling Investment (About CNY 100,000,000) For A Single Well. Well Leakage Frequently Occurred, So It Was Hard To Ensure The Cementing Quality. In Addition, The Investment Benefits Were Bad. It Was An Urgent To Use New Process, Methods And Materials To Solve The Significant Production Technology Problem. Considering The Good Reputation Of Southwest Petroleum University In Exploration And Exploitation Technologies For Complex Oil Gas Reservoirs, Tarim Oilfield Company Delegated The Difficult Task To The Research Team Of Guo. With The Cooperation Of Chuanqing Drilling Engineering Co., Ltd., Guo Led His Group To Apply The Self-Developed New Ultra-Density Large Temperature Difference Cement System To Well ZG-52  In July , 2011  Based On Materials Chemistry Related Theory And Improved Displacement Efficiency Design Method With Effective Laminar Flow, Creating A Single Stage Cementing Record In China. The One-Time Up-Return Cementing Distance Of Ultra-Density Cement Slurry Was 4,500m. The Absolute Temperature Difference Between The Well Bottom And Well Mouth Was 70℃. In Addition, The Cementing Quality Of The Whole Well Was Good; In November , 2011 , With The Cooperation Of Bohai Drilling Engineering Co., Ltd., Well ZG-514 Created A World Record For The Longest One-Time Cementing Interval With One-Time Up-Return Cementing Distance Of 5,867m, Absolute Temperature Difference Of 125℃ And Good Cementing Quality For The Whole Well, Laying A Solid Technological Base For Well Structure Scheme For Exploration And Development Of Tarim Oilfield To Simplify Well Structure And Reduce Well Construction Cost. By The End Of 2013 , 23  Wells In Tarim Oilfield Have Adopted This Technology. The Longest Single Stage Cementing Interval Reached 6,985m , Maintaining World's Leading Record. The Direct Economic Benefits Exceeded Several Hundred Million CNY. In 2014 , Based On Original Theory On Weightlessness Of Cement Slurry, Design Method And Self-Developed KQ Anti-Gas Channeling Agents, Guo Helped China National Petroleum Corporation (CNPC) To Overcome The Problems Of Karazhanbas Oilfield In Kazakhstan, I.E. Annual Increase Of Annular Pressure After The Well Cementing Which Was Unable To Overcome In The Last Three Years. The Excellence Rate Of Cementing Quality Reached Over 98.1% . The Operation Quality Exceeded Foreign Competing Companies, Greatly Improving The Overseas Competitiveness Of Chinese-Funded Companies. The CNPC Key Scientific And Technological Project Of “Research On Packaged Technology For Preventing Corrosion Of Oil Well Casing In Eastern Region Of Gansu Province And Gas Well Casing In The Central Shanganning Basin And Improving Cementing Quality” Undertook By Guo Has Overcome Well-Known Technical Problems Of Leakage And Large Damage To Casing Of Changqing Oilfield And Successfully Developed Anti-Corrosive Low-Density Cement System Which Has Been Popularized And Applied Throughout China With Direct Economic Benefits Exceeding Several Hundred Million CNY. Such Project Won First Prize For Progress In Science And Technology Awarded By CNPC; National Scientific Key Project Of “Research On Packaged Technology For Exploiting Horizontal Wells Of Karamay Oil Fields In Xinjiang” Undertook By Him Laid Technical Base For Xinjiang Oil Field To Exploit Crack-Type Volcanic Reservoirs With International Advanced Special Drilling And Completion Technologies. The Project Won Second Prize For Progress In Science And Technology Awarded By CNPC. Professor Guo Xiaoyang Believed That: One Of The Key Technologies To Improve Single Well Productivity Of Adjusting Wells In Dagang Oilfield Is To Reach Strict Inter-Layer Separation For Cementing Engineering. The Inter-Layer Separation Provides The Layer Selection And Perforation Basis For Layered Development Of Reservoir Stratum. The Layer Selection And Perforation Provides Displacement Solution Design For Water-Flooding. The Reasonable Displacement Avoids Earlier Watered-Out Of Oil Layer. The Reasonable Profile Control Of Oil And Water Layer Without Mutual Channeling Can Ensure Long-Term Effective Production Stabilization And Increase. The Key To Realize The Inter-Layer Separation Is To Improve The Cementing Quality. Therefore, Based On Years Of Scientific Research Accumulation And Existing Quality Problems Of Duanliubo, He Put Forward Purposeful Opinions And Suggestions, Such As Modifying Silicate Anti-Sloughing Drilling Fluid, Removing False Filter Cake From Well Wall, Preventing Channeling And Leakage Of Cement Slurry, Improving Replacement Efficiency, Defining Pressure Steady Equivalent Density And Optimizing And Designing The Thickening Time Of Two-Stage Cementing Cement Slurry. Staff Of Dagang Oilfield Returned And Carried Out Field Experiment Immediately. The First Test Well Achieved Good Results Of 1,200m Of Isolation Interval With Full Excellent Cementing Quality, Further Enhancing The Confidence Of Dagang Oilfield And Southwest Petroleum University In Solving The Cementing Problems Of Adjusting Wells Of 3rd Oil Production Plant Through Scientific Research Cooperation. In The Following Three Months Despite Of The Severe Winters In The North And Muddy Site, He Led The Young Teachers And Postgraduates In The Team To The Operation Site For Several Times To Exchange With Party A Of The Oilfields And Workers Relating To Well Drilling, Cementing, Geology, Slurry And Logging And Conduct Related Experiments To Scientifically Analyze The Crucial Reasons For Poor Cementing Quality. Then He Directed The 3rd Oil Production Plant, OMAX Oilfield Technology Co., Ltd. And No.2 Cementing Company Of Bohai Drilling Engineering Co., Ltd. For The Cementing Practices Around The Clock, Prepared Scientific And Reasonable Cementing Technology Solutions And Went To The Operation Site Personally To Control Each Construction Link And Closely Track The Construction Effects. Eventually, The Elastic-Plastic Quick-Setting Anti-Channeling And Anti-Leakage Fiber Cement Slurry System With Early Strength Of OMAX Has Been Optimized, With The Technical Measures For Adjusting Properties Of Drilling Fluid And Multi-Cycle Before The Well Cementing Defined, Technical Difficulties In Long New Well And Open Intervals, Complex Formation Lithology, Big Hole Deviation Angle And Disordered Pressure In Water-Flooding Position In The Old Block Overcame And 12 High Quality Wells Cemented In Duanliubo Block Successively, Turning Around The Passive Situation Of Poor Cementing Quality For Consecutive Years In Duanliubo Block. This Evoked Strong Repercussions In Dagang Oilfield And Bohai Drilling Engineering Co., Ltd.

Future Development: Endless Exploration Of Oil Field Technology

 The Good Cementing Quality Can Ensure Reasonable Exploitation Of Production Layer And Enhance The Stimulation Efficiency. The Official Data From Dagang Oilfield Shows That: 5  Wells Underwent Oil Production Test And Put Into Operation Provided 50%  Reservoir Thickness Was Perforated During Separate Strata Development. The Average Oil Output Of The Oil Wells Was 15.69t/D. In Addition, The Moisture Content In Stratum Was Greatly Reduced (24.36%), Dropped By 26% Than The New Production Wells Since 2011 . The Well DLB-39-38 , With High Test Oil Yield, Can Put Into Operation Directly, With Oil Output Of 15.31T/ D, Saving Fracturing Modification Cost Of CNY 2,000,000 ; Well DLB-38-46-1  Flowed After The Perforation. The 4mm Nozzle Flowed After The Fracture. The Oil Output Was 35.8 T/ D, More Than Twice  Of That Of The Adjacent Wells. The Single Well Productivity Has Been Greatly Improved, Making A New Way For Increasing Reserves Of Adjusting Wells In Old Blocks. These Achievements Made Dagang Oilfield Be Full Of Praise For The Professional Qualities Of The Team Of Guo And OMAX And Further Understand The Technical Strength And Faith And Perseverance In Overcoming The Difficulties Of Both Parties In Exploration And Development Field. The New Cementing Design Idea And Operating Methods Are Widely Referred And Applied By Technicians Of Bohai Drilling Engineering Co., Ltd. On This Basis, The Cementing Technology Specification For Duanliubo Oilfield Is Established And Many Cementing Experts Are Cultivated For 3rd Oil Production Plant And Bohai Drilling Engineering Co., Ltd. Besides, The Cementing Team Of Guo And OMAX Actively Participated In The Productivity Construction Of 3rd Oil Production Plant With The Thought Of “One Family” And “A Game Of Chess”, Contributing Ideas And Exerting Efforts For The Productivity Construction And Scientific Planning With Years Of Experience, And Conducting Supportive And Prospective In-Depth Construction Technology Study On Special, Complicated And Key Wells Of 3rd Oil Production Plant Based On New Cementing Process And Technologies, To Provide Good Technical Base For Dagang Oilfield To Solve The Cementing Problems Of Adjusting Wells In Old Oilfields Over Long Term. The Potential Tapping In Old Block Is Mainly Used In China For Increasing The Reserves Currently, While The Cementing Quality Of Adjusting Wells Can Improve The Single Well Productivity Of Old Oilfield And Ensure The Simulation Efficiency And Implementation Effect Of Development Program. The Cementing Quality Breakthrough In Long Isolation Interval Of Adjusting Wells Of Dagang Oilfield Has Successfully Solved The Cementing Problems Over The Last 40 Years, Fully Displaying The Scientific Research Ability And Status Of OMAX And The Team Of Guo In Oil Well Cementing Engineering Field And Also Marking A New Road For Transforming The Science And Technology Into Productivity In Reserves Increase Of Adjusting Wells In China’s Large Oilfields. “The Achievements Made Before Are Some Applied Research In Cementing Field Through The Scientific Method And Technological Approaches. In Fact, We’ve Made A Small Step Towards The Long Journey. It Is Only The Starting Point For Related Research. From Now On, We Will Expand Research Field Laterally And Dig The Research Depth Longitudinally. “Said Engineers Of OMAX. Basic Level Researchers Like The Team Of Guo, OMAX And 3rd Oil Production Plant, Are The Backbones In Oil Industry Of The Chinese Nation With Their Resilience And Tenacity And Responsibility And Wisdom And Win The Respect Of The World!  They Also Open A New Chapter For Scientific Research!