法国专家讲稿钻具失效分析Failure_on_drill_string_EN_&ampamp;_CN_[Compatibili.pdf

Failure on drill string 钻钻柱柱断断裂裂破破损损钻钻柱柱断断裂裂破破损损 Presented by Francois Kessler Failures on drill string 钻柱断裂破损原因 Fatigue = approx. 70 % of the failures. 疲劳断裂=约70%因此原因断裂 String design 管柱的设计管柱的设计 Handling. 使用操作 Environment 环境 Corrosion腐蚀 Formation 岩层 Fatigue疲疲劳劳断断裂裂 Most common failure mode 最常见的断裂破损形式 Initiation of the failure always perpendicular to the axis of rotation 断裂的起始线始终与旋转轴垂直断裂的起始线始终与旋转轴垂直 Happen in stressed region and / or in notch ( Last engaged thread, slips marks, change of cross section, etc) 在受力区域和/或者凹槽中疲劳断裂（最后接合的螺纹、 卡瓦痕、横截面转换处等等） Fatigue in bore back connection 背背面面连连接接疲疲劳劳断断裂裂 Drill collars are prone to develop fatigue crack at the connection bore back / last engaged thread. 钻铤易在背面连接/最后接钻铤易在背面连接/最后接 合的螺纹处产生疲劳断裂 Called twist off 所谓的扭裂（扭断） Fatigue in the box母母扣扣疲疲劳劳断断裂裂 压力 易疲劳断裂的薄 弯曲 易疲劳断裂的薄 弱点 弯曲 API Bending stress ratio API弯弯曲曲强强度度比比值值 Balanced connection: Zb = 2.5 Zp 平衡连接 Zb = 2.5 Zp BSR抗抗弯弯强强度度比比值值 2.75 to 2.25 to 1 is usually acceptable. 通常2.75: 2.25: 1的比值是可以的 3.40 to 1 will perform satisfactory with low torque connection 低扭矩时3.40:1 的比值会比较好低扭矩时3.40:1 的比值会比较好 3.00 to 2.50 to 1 is recommended in abrasive formation 在腐蚀性地层推荐采用3.00: 2.50: 1的比值 Avoid H90 connection on small DC. 避免短钻铤H90连接。 Cold roll 冷轧 Fibers in compression after cold rollafter cold roll 冷轧后压力结构 滚 动 Fatigue Resistant Connection 抗抗疲疲劳劳断断裂裂接接头头设设计计 Early fatigue weak point 易最先产生疲劳断裂的薄弱点 Elevator Shoulder crack on DC 钻钻铤铤吊吊卡卡台台肩肩上上的的裂裂缝缝 Causes: 成成因因 - Abrupt cross section change 横横断断面面转转换换突突变变 - Stress concentration 压压力力集集中中 - Corrosive environment 腐腐蚀蚀性性环环境境 HWDP fatigue加加重重钻钻杆杆疲疲劳劳断断裂裂 Happen at cross section change 发生在横断面转换处 Called washout 即通常所说的冲蚀（冲 毁） Type of HWDP加加重重钻钻杆杆的的种种类类 常规 三 螺 旋 螺 旋 加 重 Length of connections接接头头长长度度 Pin weak fatigue failure 公公扣扣薄薄弱弱疲疲劳劳断断裂裂 -未上紧 -耐力（耐久性）有限 Finite Element Analysis of connection 接接头头的的有有限限元元分分析析 母母 扣扣 公公 扣扣 最最低低 最最高高 压压力力级级 Low Stress Connection 低低压压力力连连接接 String design钻钻柱柱设设计计 Exceed mechanical properties of the drilling string 超出（优于）钻柱的机械性能 Tapered string. 锥形钻柱 Bell Boxes钟钟形形（锥锥形形）母母扣扣 Cause: excessive torque. 起因：过度扭矩起因：过度扭矩 Tube failure管管体体破破损损断断裂裂 Exceed tensile limit. 超出拉力极限 Exceed tension /torsion combined/torsion combined loading 大于扭力及拉力的联合 施力 Pin weak over torque 公公扣扣无无法法承承受受扭扭矩矩 Cup type pin failure due to over torque 杯形公扣因扭矩过度断杯形公扣因扭矩过度断 裂 Called twist off 通常所说的扭断 Eccentric wear偏偏磨磨损损 Cause: pipes run in compression. 成因：管子在压力作用下旋转 Bent pipe 弯管弯管 In vertical wells: check BHA weight 在垂直井中：检查底部钻具组 合的重量 in deviated wells check critical buckling load. 在斜井中：检查压曲临界载荷 Tapered string锥锥形形钻钻柱柱 Tapered Bottom Hole Assembly 锥锥形形井井眼眼下下部部 Rule of Thumb ( no more than 2” diameter change on 90 ft) 依经验（90英尺变化不超过2”直径） Stiffness ratio or section modulus is: moment of inertia / radius to outer fiber 刚度比值或断面模数为：转动惯量/外层结构半径 maximum stiffness ratio between drill pipes and collar : 5.5 钻杆与钻铤之间最大刚度比值：5.5 for severe drilling conditions ratio = 3.5 恶劣钻探条件下的比值=3.5 Handling damages 装装运运（操操作作）损损坏坏 Shoulder galling: 台肩磨损 Doping 有杂质（上丝扣油）有杂质（上丝扣油） under torque 扭矩不足 over heat by friction 因摩擦过热 Handling damages 装装运运（操操作作）损损坏坏 Washout in the connection 接头冲毁 Shoulder damages while Shoulder damages while stabbing 下管入井时台肩受损 Insufficient torque 扭矩不足 Handling damages 装装运运（操操作作）损损坏坏 Slips damages 卡瓦损坏 Tong Die Marks大大钳钳牙牙板板痕痕 Detrimental to casing 对套管不利对套管不利 increase wear on tool joint 使钻具接头磨损加剧 Bent pipes弯弯管管 Make up or brake out height 上紧或卸开的高度上紧或卸开的高度 storage and transportation 存储和运输 Handling damages 装装运运（操操作作）损损坏坏 Thread damages 丝扣（螺纹）损坏 check doping, speed to make up, alignment while making upup, alignment while making up 检查上丝扣油、上紧速度、上 紧时是否校直调准 break in procedures 在使用过程中破裂损坏 anti galling treatment 抗磨损处理 Handling damaged unclassified 其其他他装装运运（操操作作）损损坏坏 Environment damages 环环境境损损害害 Corrosion: H2S, CO2, etc use inhibitors 腐蚀：H2S, CO2等腐蚀：H2S, CO2等 Mud : PH, solids content 泥浆：PH, 固相含量 Formation. 岩层，地质构造 Failure conditions in H2S H2S(酸酸性性）环环境境下下破破损损断断裂裂的的条条件件 Failure in H2S require 4 conditions: 在H2S（酸性）环境下破损断裂需具备4个条件 H2S Environment H2S（酸性）环境 Stress 压力 Material sensitive to H2S 材质对H2S的敏感性 Time of exposure to H2S 暴露在H2S中的时间 H2S assisted failure H2S使破损断裂速度加快 -钢的颜色 - 典型的裂缝分支走向 Corrosion腐腐蚀蚀 Pitting 麻点腐蚀、锈斑 Galvanic 电（化学腐）蚀 Erosion Erosion 风蚀、冲蚀 Crevice 裂缝腐蚀 Exfoliation 球形风化，页状剥离 Formation damages岩岩层层破破坏坏 Mechanical wear 机械磨损机械磨损 Formation damages岩岩层层破破坏坏 Wear on diameter change 直径转换的磨损直径转换的磨损 use of hard facing 耐磨带失效（耐磨带渐 渐消失） Washout in the tube管管体体冲冲蚀蚀 Corrosion / mud PH 腐蚀/泥浆PH(酸碱）腐蚀/泥浆PH(酸碱） Geometry of the tube 管体的几何形状 Thank you ! 谢谢！谢谢！