2023年5月
特别关注:完井技术

自动化完井地面系统:24/7 压裂之路

通过识别阻碍 24/7 油藏压裂的众多障碍,新开发的系统采用了先进的工艺和技术。该系统提高了运营效率、一致性和安全性,与标准程序和技术相比,操作员每天可以更多时间对储层进行压裂。
Tim Marvel / SEF Energy Austin Johnson / Downing Phillip Douget / Blue Ox Resources Michael Mast / Blue Ox Resources John Dyer / SEF Energy Jordan Kuehn / SEF Energy Brian Wiesner / Downing

2018 年,内部提出了第一个为压裂堆栈添加自动化的框架。该提案要求通过实时数据流和工作后分析为液压阀添加传感器和自动控制装置。此后不久,发现并获得了一项新颖的第三方技术。将服务公司的运营专业知识与第三方的自动化专业知识相结合,形成了一个广阔的愿景,可以有条不紊地消除油藏压裂的主要障碍(24/7)。

这些障碍被确定为: 1) 阶段之间的时间(包括过渡时间和压力测试);2) 与闸阀维护和故障相关的停机时间;3)泵的维护;4) 沙和水物流将通过新颖、适合用途的产品、自动化工作流程和集成控制系统来消除。

制定了路线图,强调持续的系统开发和提高自动化水平,克服每个障碍,如图 1 所示与自动驾驶车辆的路线图类似,水力压裂路线图利用对功能和子系统的连续改进和集成,以实现更高水平的自主性、安全性和一致性。表 1描述了每个自动化级别及其对安全性、一致性和泵效率的影响。

图 1. 24/7 水力压裂路线图。
图 1. 24/7 水力压裂路线图。

地面系统目前已集成到单个子系统中,实现了4级自动化。该子系统集成到电缆和泵子系统中,为实现 5 级奠定了基础。相比之下,大多数操作员使用 2 级地面系统,这些系统采用多个非集成控制,将大多数过程控制留给检查表、程序和人工专业知识。

自动化地面系统(Freedom Series Completion System)实现24/7。已经发表了几篇关于处于初始阶段的自动化地面系统的论文。自动化地面系统具有以下组件,其中突出显示了最近的一些升级以了解更多详细信息:

  • 基础系统 
    • 自动闩锁(自由系列闩锁)
    • 自动化阀门(自由系列阀门) 
  • 自动化阀门控制器 (Freedom 系列 iControl)
    • 控制所有闸阀。
    • 每次启动时自动润滑所有阀门
    • 通过泵送时的自动阀门转换实现连续泵送操作。
    • 新的润滑算法确保每个阀门都能获得适量的润滑脂,而仅使用传统润滑脂的一小部分。
    • 导致全天在治疗压力下进行多日压裂。
  • 自动润滑器 
    • 自动执行润滑器的预填充和均衡。
    • 包括获得专利的自动排气接头技术和 RFID 技术。
  • 自动导弹均衡 
    • 通过快速降低压力来减少更换泵所需的时间。
    • 准确、快速地使导弹与井口平衡。
    • 消除导弹压力释放时进入红区的人员。
  • 自动泵更换(Freedom 系列热插拔)
    • 自动执行更换泵的过程,而不会在泵送时进入红色区域。

这些系统组件集成到一个单一的自动化地面系统中,使操作员能够日复一日地从一个阶段即时连续地过渡到下一个阶段。该系统通过以下方式消除了 24/7 泵送的四大障碍:

  • 阶段之间的时间(包括过渡时间和压力测试)
    • 基础系统和自动阀门控制器可在泵送时实现近乎瞬时的阀门转换(小于 30 秒)。
  • 与闸阀维护和故障相关的停机时间。
    • 基本系统无需使用烟囱进行过渡关井,仅在需要关井时才使用烟囱闸阀。
    • 每次启动阀门时,系统都会使用填充腔体所需的精确润滑脂量来润滑阀门,不多也不少。AGA 部分对此进行了更详细的描述。这种方法大大减少了维修和故障。
  • 泵的维护
    • 新的自动泵更换系统使得在泵送过程中无需进入红色区域即可更换泵,从而无需关闭压裂作业来修复泵。此外,现在可以对泵进行预防性维护计划,从而延长每台压裂泵的正常运行时间并降低维修成本。
  • 砂水物流
    • 尽管该系统不直接解决沙子和水物流问题,但能够实现更一致的压裂作业的系统有助于规划沙子和水物流。

自动润滑器可缩短决策时间以及潜在的 NPT 事件:

  • 自动检测哪口井上有哪个润滑器。由于自动化地面系统可以加快操作速度,阶段之间几乎没有时间,并且随着同步压裂的引入,操作员正在选择在作业中使用多台电缆卡车。为了确保自动化地面系统知道哪口油井上有哪个润滑器,采用了 RFID 技术来主动识别这种关系。
  • 一旦润滑器被 RFID 检测到,系统就会自动锁定润滑器,从而消除过程中的人机交互步骤。
  • 完成阳性测试后,系统会填充润滑器,直到新的自动排气接头检测到液体。这样做是为了确保所有空气都排出润滑器,因为当今的手动口水管线或排气接头无法保证空气从润滑器中排出,由于均衡过程中的绝热加热,可能会导致电线烧毁。此外,该系统设计有两个泵,一个用于填充,另一个用于平衡压力,填充泵无法产生足够的压力来引起绝热加热。凭借这些功能,自动通风接头消除了烧毁电线的问题。

自动导弹均衡。在当今的许多压裂作业中,人员进入红色区域以排出导弹。集成到自动化地面系统中的是从压裂车的安全性中对导弹进行放气和均衡,从而缩短了关闭泵所需的时间并将人员从危险的红区作业中转移出来。这使得压裂人员始终处于完全无红区的状态,消除了任何例外的需要。通过自动润滑平衡旋塞阀,消除潜在的 NPT 源,节省了额外的时间和费用。

自动泵更换。剩下的关键障碍是确保泵每天 24 小时运行,以保持按规定的速率进行泵送。如今,使用拉链的压裂人员平均每天工作 16 小时,当这个问题得到解决后,每天的泵送量将增加 50%。图 2 突出显示了采用自动泵交换技术的潜在效率和利用率收益。

图 2. 效率机会,从传统的拉链操作转向自动化表面系统,无需自动泵更换,然后再进行自动泵更换。
图 2. 效率机会,从传统的拉链操作转向自动化表面系统,无需自动泵更换,然后再进行自动泵更换。

传统的泵维护方法主要集中在泵车的改进上。自动地面系统中的自动泵更换功能以不同的方式解决了这个问题,它可以在不停止操作或人员进入红色区域的情况下更换泵。该系统放置在每个压裂泵和导弹之间。当泵需要维修或更换时,系统会隔离泵、降低压力并解锁泵。然后,泵车被移出红色区域进行维修或更换为另一辆卡车。

修复后的泵车返回到设定位置,驱动臂将自动泵交换滑橇与安装在卡车后部的软管板连接起来,并将软管板夹紧。在泵恢复在线之前,会执行灌注升压测试和均衡。凭借自动化地面系统的优势,这项附加技术使操作员能够实现每天 24 小时泵送。对泵工的好处包括更高的泵车利用率、更高的收入、每月更多的压裂作业以及在任何给定平台上维持泵率所需的卡车更少。原型机于 2022 年 7 月进行了测试,在不停止压裂作业的情况下成功完成了八次泵更换,如图 1 和 1 所示。3和4从原型中吸取的经验教训已融入到最终产品中。

图 3. 自动泵交换撬的第一个原型
图 3. 自动泵交换撬的第一个原型
图 4. 第一个泵车原型。
图 4. 第一个泵车原型。

行业第一

为了实现所需的 24/7 压裂目标,下面概述了一些行业第一。

自平衡自动阀。该基础系统于 2019 年实现商业化,可自动执行均衡过程,从而实现快速过渡。

远程集成闩锁。作为基础系统的一部分,集成闩锁与自动阀门互锁,通过确保闩锁在阀门启动之前经过正确测试并就位,消除了潜在的压力释放。此外,该系统允许在压裂期间连接润滑器,从而消除了执行此任务的关键路径上的时间。

数字握手。每 30 秒更改一次的唯一身份验证代码与每个有权使用该系统的人相关联。数字握手可确保系统仅由合格人员操作,并在出现问题时提供可追溯性,从而降低 NPT 风险。

远程液压润滑。其他润滑系统传统上使用气动装置来驱动润滑脂。使用液压系统可提供压力曲线,提供润滑脂保证,消除润滑时间并减少与阀门相关的 NPT 事件。

表面系统的集成。传统的地面系统具有多个非集成控制装置。为了便于说明,典型的地面系统对每个阀门、润滑系统和闩锁系统都有单独的控制。过程控制是通过人为驱动的工作流程、清单、标牌、上锁/挂牌来实现的。人为驱动的工作流程很容易出错,因此存在 NPT。Freedom系列完成系统将这些子系统完全自动化为一个集成系统。

连续抽油井过渡。第一次连续泵送过渡于 2020 年 10 月在美国东北部进行。连续泵送是一种将阶段到阶段的过渡时间缩短至数秒的过程。

24小时连续泵送。这一里程碑于 2021 年 9 月首次实现,代表着朝着 24/7 连续泵送迈出了第一步。

远程压裂计划执行。能够从完井工程师输入的远程压裂计划执行下一个井过渡,为工程师提供压裂灵活性,并确保完成正确的阶段。该系统维护压裂井队列,并将按照规定的步骤工作,建议按照电缆活动的顺序进行交换,或者从完井工程师提供的阶段列表中提取。无论哪种方式,它都会从可用的压裂井中移除该井,直到再次看到电缆活动。它消除了交换时的人为决策因素,随着我们进入 5 级自动化,提供了自动交换的能力。

治疗时更换泵。于 2022 年 7 月展示。

自动模拟转换。2022 年 5 月,自动化地面系统适应了 simulfrac 作业,消除了 simulfrac 作业的逐阶段时间。

在 simulfrac 作业中连续泵送。2022 年 5 月,自动化地面系统从两口井过渡到两口独立的井,执行 11 次阀门驱动,并启动每个阀门的润滑,所有这些都在 40 秒内完成,从而有机会在 simulfrac 作业中进行 24/7 泵送。

为什么选择自动化?

当新技术取代当前实践时,引发的由来已久的争论是有据可查的。今天,在压裂界也可以听到与地面系统自动化相关的同样的争论。从历史上看,OFS 一直手动完成 Downing(SEF 能源公司)自动执行的操作(但您每次都这样做吗),我们需要在采用新系统之前解决所有问题(SEF 的系统消除了许多问题,这样您就可以专注于其他问题),我们的泵无法跟上,我们有沙子和水问题。

辩论中丢失的是每个问题都掩盖了另一个问题。如果您有泵问题,这可能是掩蔽阀问题;供应问题可能掩盖了泵问题。此外,如果没有可用的高分辨率数据,确定问题的根本原因通常很困难,有时甚至是不可能的。流程改进涉及系统地消除一个问题,然后专注于下一个要解决的问题。参考图1中的路线图,0级到3级自动化涉及功能之间的人机交互,需要耗时的流程、检查表和人员专业知识。如前所述,当问题不可避免地发生时,很难通过板上不同的系统找到根本原因。

随着时间的推移,人员发生变化,流程纪律和经验都会消失,导致操作员再次遇到他们认为已经解决的问题。第 4 级和第 5 级中的自动化工作流程由捕获每个系统功能的一秒数据驱动。系统数据和自动化工作流程通过两种方式减少非生产时间:1)通过实时警报警告操作员即将出现需要解决的问题;2) 通过根本原因分析,积极识别导致 NPT 发生的问题,并通过工程设计和/或编程消除自动化特有的问题,从而永久消除该问题。

图 5说明了为什么自动化是永久消除问题的关键。随着时间的推移,系统变得更加稳健,从而实现更快、更一致的压裂作业。为了说明这一概念,系统最初使用井筒流体通过球阀和节流阀进行平衡。流体中的沙子会导致球阀磨损。此外,节流器的尺寸必须根据油井参数进行适当调整。认为这是一个改进的机会,球阀被设计在系统之外,代之以增压泵和清洁流体,以执行均衡并填充润滑器。

图 5. 选择自动化工作流程相对于人工驱动工作流程的优势
图 5. 选择自动化工作流程相对于人工驱动工作流程的优势

分析提高效率

自动化地面系统每次作业都会生成千兆字节的数据,跟踪从压力到阀门位置,再到打开和关闭事件的所有信息。这些数据被实时用于

锁定,确保系统仅在规定条件出现时运行。此外,这些数据还用于实时和井后分析,以提高操作员绩效。这些数据还用于故障模式分析,从而为识别潜在 NPT 的警报提供新的签名。下面重点介绍了一些数据应用程序。

操作仪表板。自动化地面系统独有的操作仪表板(图 6)为操作员、现场服务人员和远程操作人员提供了维护地面系统的界面,防止 NPT 事件发生,并识别改进机会即时的。仪表板对运营数据进行趋势分析,提供所有系统的实时状态,向人员发出潜在故障以及预测性维护事件的警报,并提供运营改进的见解。

图 6. 显示实时自动化地面系统状况的操作仪表板
图 6. 显示实时自动化地面系统状况的操作仪表板

自动化地面系统最近添加了自适应润滑脂算法 (AGA)。AGA 的开发是为了确保所有闸阀在每次启动时都得到正确润滑(定义为用润滑脂填塞润滑脂空隙,然后停止),从而减少润滑脂和阀门维修成本并消除阀门过早失效。这既确保了每次驱动时润滑脂空隙都充满,同时也消除了多余的润滑脂以及与钻孔中的润滑脂相关的后续问题。

首次部署于 2022 年 10 月进行,取得了惊人的结果,如表 2 所示在实施 AGA 之前和之后测量了对每个拉链、抽气和叠加阀进行润滑的泵冲程(与消耗的润滑脂量相关)。总体而言,所有阀门的润滑脂量减少了 55%(参见邻表),并且对阀门维修或 NPT 没有不利影响。随后应用 AGA 后,润滑脂量减少了 90%。

计算并绘制锁存间 (L2L),作为钢丝绳周转时间的测量,从解锁钢丝绳的时间到钢丝绳被刺穿并再次锁定的时间,图 7除了 L2L 之外,填充和排放时间也精确到秒。

阶段到阶段(S2S)时间在两个位置定义:1)在规定压力(刚好在治疗压力下)下的阶段之间的时间和2)在治疗压力下的时间,图8阶段到阶段捕获阶段之间的空白空间,主要包括过渡时间、压力测试时间、非泵维护时间以及压力上升/下降和泵维护时间。它还包括非生产性泵送 (NPP) 时间,定义为转换后但压裂恢复到处理压力之前的时间,在传统泵效率计算中未捕获。NPP 包括提高压力、压力测试和在关键路径上发现酸的时间。

图 7. 锁存时间突出了有线周转效率。
图 7. 锁存时间突出了有线周转效率。
图 8. 阶段到阶段时间计算。
图 8. 阶段到阶段时间计算。

级间比泵效率更能反映工作效率。泵效率存在多个缺陷,导致很难将一项工作与另一项工作进行比较,其中包括:

长阶段与短阶段。长级人为地提高了泵的效率。比较两项压裂作业,一项具有长阶段(例如 3 小时),另一项具有短阶段(例如 1 小时),由于较短阶段转换的运营成本,较长阶段作业可能被认为更高效。这可能会给人一种错误的印象,即一个团队比另一个团队更好。顺便说一句,通过自动化地面系统显着降低了过渡的运营成本,为完井工程师在设计处理方案时提供了更大的灵活性(即通过较短的阶段为有限进入压裂提供额外的选项)。

定义计算。每个操作员或每个压力泵机都没有以一致的方式获取泵效率。这会导致比较不同的工作人员、操作员或压力泵工时出现错误。

包括 NPP(非保护性泵送)。泵送时间通常在转换之后但在泵送器返回处理压力之前开始。回想一下在治疗压力下 24/7 泵送的目标,过渡只是阶段之间时间的一部分。如上所述,阶段之间的时间还可以包括 NPP、缓慢加速时间和等待。这不仅提供了错误的效率衡量标准,而且当按泵小时计费时,一项工作的成本将会更高。

为了比较一项工作与另一项工作的效率,将 S2S 绘制在从 0.5 分钟(分钟)到 60 分钟范围内的直方图上。阶段之间,图9阶段与阶段之间的关系以阶段总数的百分比形式绘制。例如,使用图9,0.5分钟内为28%。范围表示 28% 的阶段在不到 30 秒内完成转换,代表连续泵送操作(连续泵送通常在 30-60 秒范围内)。60 分钟。如果超过 60 分钟,则选择桶作为截止点。表明焊盘上存在可能持续数天的严重问题,从而不必要地扭曲 S2S。这也是工作质量的一个指标,60 分钟内的百分比较低。桶(<90%)表明比典型垫更多的问题。

图 10突出显示了以总体平均时间绘制的 S2S,其中 95% 的置信区间显示了整个作业中转换的一致性。如前所述,S2S 持续时间超过 60 分钟。已被删除,因为更大的问题,一些持续的日子,可能会扭曲本来是一份出色的工作。

图 9. 阶段到阶段直方图,记录作业与两个基准的效率
图 9. 阶段到阶段直方图,记录作业与两个基准的效率
图 10. 平均阶段间时间、作业的 95% 置信区间和两个基准。
图 10. 平均阶段间时间、作业的 95% 置信区间和两个基准。

信息安全计划

尽管不是普遍做法,但许多运营商利用 ISIP 来衡量每个压裂阶段的质量。传统上,这需要将油井关闭一段时间。工程师在屏幕上选择几个点来建立 ISIP 号码。这种做法存在几个问题,包括:1) 最多需要 5 分钟。在关闭操作的阶段之间;2) 工程师需要时间收集并手动选取压力曲线上的点;3) 根据计算 ISIP 的人员的经验水平,可能会不一致。

操作员要求根据地面系统数据自动执行此过程。他们认识到,通过利用自动化地面系统,可以计算 ISIP,而无需运营或管理成本。该系统在整个作业过程中对每口井开放,无需在阶段结束后在特定井上停留几分钟等待捕获数据。此外,冗长的ISIP数据过程包括下载数据、绘制数据以及手动捕获ISIP。该过程是自动化的,由特定井上的自动化地面系统边缘计算机实时执行,利用导数来捕获 ISIP。然后 ISIP 被传输到云端,工程师可以在云端下载每个阶段的具体数字。

为了验证结果,经验丰富的工程师使用“高级 ISIP”方法手动捕获 ISIP 数据,并将其与来自自动化地面系统的 ISIP 以及泵送公司提供的 ISIP 进行比较。图 11突出表明,来自自动化地面系统的系统派生 ISIP 与高级 ISIP 几乎完全匹配,从而确定了自动化地面系统 ISIP 计算的准确性。黄色的 ISIP 点(从压力泵收集)显然因连续泵操作而存在缺陷,而且在人类水平上收集的数据也存在固有的不一致。

图 11. ISIP 操作员计算(高级 ISIP)与自动 ISIP 与泵机 ISIP。
图 11. ISIP 操作员计算(高级 ISIP)与自动 ISIP 与泵机 ISIP。

案例1

Blue Ox Resources 是一家私募股权支持的特拉华州二叠纪盆地公司,总部位于德克萨斯州达拉斯,在与前公司 Primexx 合作使用自动化地面系统后,选择采用该系统。Primexx 是自动化地面系统的早期采用者,并在过去三年中为其发展贡献了见解。选择该系统的原因是它的效率、消除人为错误、防止空头或切断钢丝绳的联锁装置,以及通过将人员从红色区域和垫上移走来保证系统的固有安全性。凭借之前的经验,并采用自动化地面系统的最新功能,Blue Ox Resources 在 El Duderino East 和 El Duderino West 焊场上使用该系统创造了新的效率记录(图 12)。

图 12. 阶段与阶段之间的直方图显示了利用自动化表面系统的效率差异。
图 12. 阶段与阶段之间的直方图显示了利用自动化表面系统的效率差异。

El Duderino 油田(图 13 )位于德克萨斯州佩科斯以南,各由 3 口井组成,间距 200 英尺(图 14)东赛场共有 130 个赛段,西赛场共有 126 个赛段。泵送时间平均为 110 分钟/阶段(在处理压力下),并使用 100 目砂。堆栈配置(手动阀、液压阀、四通阀、基本系统位于四通阀顶部)的额定值为 15k。拉链由两个液压阀组成,这两个液压阀在转换过程中均被驱动,提供恒定的双重屏障。压力泵提供了 22 个 Tier II 泵,制造日期为 2007/2008 年。

图 13. Blue Ox Resources  埃尔杜德里诺垫。
图 13. Blue Ox Resources 的 El Duderino 基地。
图 14. 操作员 2 人员在压裂车上操作自动化地面系统。
图 14. 操作员 2 人员在压裂车上操作自动化地面系统。

为了维持速率,任何时候都需要 16 个泵。压力泵合同不包括任何强制维护期。压力泵工确实有内部人员激励措施,可以每天泵送更多小时。压力泵运行直至减少到 16 个泵,完成关闭前的阶段。然后操作员关闭停机坪,修复不运行的泵,并对其他泵进行预防性维护。一旦 18 到 20 个泵准备就绪,压裂作业就会恢复。

在开展这项工作之前,Blue Ox Resources 要求地面系统提供商、电缆和压力泵代表以及现场操作员会面,以充分了解自动化地面系统及其运行方式。Blue Ox Resources 预计每天至少抽水 10 个阶段,并且每个阶段都可能进行连续抽水。

利用阶段到阶段的时间来准确判断表现,将 Blue Ox Resources 作业与特拉华盆地之前的 15k 记录进行比较,如图 15 所示2021 年 9 月,记录了第一个连续泵送 24 小时的作业(后续记录在同一垫上设定为 35 小时),该作业的平均 S2S 时间为 10 分钟,连续泵送了 50% 的阶段。

图 15. 运营商 2 El Duderino 结果与区域基准对比
图 15. 运营商 2 El Duderino 结果与区域基准对比

同年,Operator 1 的 Nimitz pad 将 S2S 平均时间降低至 9.2 分钟。操作员 2 的两个垫的平均 S2S 降低至 5.4 分钟。2022 年 12 月,分别需要 3.3 分钟和 3.3 分钟,连续泵送 70% 的级。最新的 Operator 2 作业也收紧了 95% 置信区间,记录了 S2S 的一致性。24/7 连续泵送的作业将在图 12的左上角显示 100% 这两项工作每天都可完成 10.6 个赛段,其中 El Duderino East 每天可完成 10.7 个赛段。

案例2

如上所述,自动泵交换系统的第一个版本于 2022 年 7 月进行了测试,该测试验证了耦合/解耦序列。从第一次迭代中吸取的经验教训已应用于第二个原型,包括:

  • 隔离撬块内的泵振动。
  • 与泵和导弹无关的连接系统(即系统只需稍作修改即可与任何泵或导弹一起使用)。

修订后的系统于 2022 年 1 月下旬在 Operator 2 的 Gutterballs State 14-15 训练场上进行了测试。正在测试的系统利用了一个连接到导弹的导弹自动化撬块(使任何导弹的功能自动化)和两个自动泵交换撬块,每个撬块通过导弹自动化撬块连接到一侧的压裂泵和另一侧的导弹,图1。 16 .

图 16. 自动泵交换系统配置。
图 16. 自动泵交换系统配置。

每个压裂泵都经过改造,在卡车背面的固定位置安装了一个简单的板。该板包含连接到压裂泵的泵高压和低压管线的两个接头,图 18适用于任何压裂泵,这使得一个制造商的压裂泵可以与第二个制造商的压裂泵互换。当每个泵退回到撬块中时,就会运行耦合序列,将压裂泵固定到自动泵交换撬块上。然后打开吸入阀和排出阀,允许压裂人员在压裂作业开始之前在初始装置上运行正常的压力测试程序。耦合泵和自动泵交换橇如图 17所示

图 17. 与泵(左)耦合的自动泵交换撬(右)
图 17. 与泵(左)耦合的自动泵交换撬(右)
图 18. 改装压裂车显示带有两个接头的板。
图 18. 改装压裂车显示带有两个接头的板。

在泵离线的情况下运行多个耦合和解耦序列以验证耦合序列。然后测试在继续压裂的同时自动更换泵。这包括隔离需要维修的泵、对泵进行排气以及在其余泵继续压裂时解耦。然后,这些泵在红色区域外进行了维修,拉回到自动泵交换橇中,进行耦合、启动、压力测试和均衡(吸入和排出管线打开),使泵恢复在线状态,同时其余泵继续泵送。这样做了四次,每次测试都比前一次测试更严格。四次测试的结果如表3所示

从第一次迭代中吸取的两个关键经验教训,即使系统与泵和导弹无关,以及隔离泵振动,已成功集成到系统的第二个版本中。该系统按预期工作,并正在集成到自动化地面系统中。新的自动化泵交换系统现已投入生产,并将作为自动化地面系统的组成部分进行部署。

结论

自动化地面系统 Freedom Series 完井系统已经开发出来,可以系统地消除油藏压裂的主要障碍(24/7)。通过将压裂和电缆系统集成到自动化地面系统中,该系统已成功在多个垫上连续泵送多天。24/7 压裂的最后一个障碍是消除泵维护这一障碍。随着自动泵更换的出现,这一障碍已被消除。该系统现已到位,可实现连续 24/7 压裂作业,并且随着不断发展,自动化地面系统已接近 5 级自动化。

致谢

作者要感谢 ProFrac 帮助测试自动泵交换系统的第二次迭代。另外,感谢 Liberty Energy 和 Steward Energy 帮助测试系统的第一次迭代。本文包含 SPE 论文 213101-MS 的摘录,“自动化完井地面系统:24/7 压裂之路”,该论文于 4 月 17 日在俄克拉荷马城会议中心举行的 SPE 俄克拉荷马城石油和天然气研讨会上发表。 2023 年 19 日。

关于作者
蒂姆·马维尔
海基丰能源
Tim Marvel 是 SEF Energy 的业务开发和技术副总裁。在加入 SEF Energy 之前,他曾在贝克休斯 (Baker Hughes)、美国铝业 (Alcoa) 和多佛 (Dover) 担任过各种国内和国际高管职务。Marvel 先生毕业于科罗拉多矿业学院,获得机械工程学士学位,并且是德克萨斯州的注册专业工程师。他拥有 21 项专利,并与人合着了 9 篇技术和贸易期刊文章。
奥斯汀·约翰逊
唐宁
奥斯汀·约翰逊(Austin Johnson)是唐宁的完成副总裁。在加入唐宁之前,他曾在 Oil States 担任过各种运营和管理职务,并在职业生涯初期拥有一家企业。他专注于完井优化,他的专业知识在自动化完井系统的开发中发挥了关键作用。Johnson 先生拥有多项自动完成技术专利。
菲利普·杜吉特
蓝牛资源
Phillip Douget 是 Blue Ox Resources 二叠纪盆地副总裁兼总经理。在加入 Blue Ox 之前,他曾在 Primexx 担任综合服务规划经理和中游经理。在这些职位上,他管理了 10 亿美元的资本投资,并监督特拉华盆地 Primexx 天然气和水基础设施的建设。他的职业生涯始于哈里伯顿,曾在钻井、完井和水管理领域担任过各种职务。Douget 先生毕业于西北州立大学,获得学士学位。
迈克尔·马斯特
蓝牛资源
Michael Mast 是 Blue Ox Resources 的工程副总裁。在加入 Blue Ox 之前,他曾在 Primexx 担任地下工程经理。他的职业生涯始于哈里伯顿,担任过各种工程职位,最终结束了作为技术团队成员的身份。Mast 先生毕业于 Rose-Hulman Institute of Technology,获得化学工程学士学位。
约翰·戴尔
海基丰能源
John Dyer 致力于为 SEF Energy 开发自动化完井设备。他还将自己的专业知识应用于心脏电生理学、航空和导航以及机载气象雷达领域。他的主要研究兴趣是仪器仪表和测量、数据采集以及采集数据的信号处理。Dyer 博士拥有俄克拉荷马州立大学生理学学士学位、俄克拉荷马大学学士和硕士学位以及电气工程博士学位。他教授过电气工程初级和高级课程,并开发了统计数字信号处理研究生课程。
乔丹·库恩
海基丰能源
Jordan Kuehn 专注于为 SEF Energy 的 Freedom Series 自动完成系统设计控制系统。他的职业生涯始于 Colex Group,为航空航天、国防和能源公司设计和构建自动化生产线末端测试系统。Kuehn 先生于 2009 年获得了俄克拉荷马大学计算机工程学士学位(主攻数字信号处理),并于 2010 年获得了电气和计算机工程硕士学位。他拥有一项专利。
布赖恩·维斯纳
唐宁
Brian Wiesner 是 SEF Energy 表面系统总裁,该公司由 Downing 品牌组成。他于 2015 年加入 SEF,此前他在 Baker Hughes、FMC Technologies 和 GE Oil & Gas 担任过各种技术、管理和国际职位 20 年。Wiesner 先生拥有科罗拉多矿业学院的工程学学士学位以及康奈尔大学和皇后大学的 MBA 学位。
相关文章 来自档案
原文链接/worldoil
May 2023
Special Focus: Well Completion Technology

Automated completion surface system: The path to fracturing 24/7

By identifying the numerous barriers obstructing 24/7 reservoir fracturing, a newly developed system utilizes advanced processes and technologies. The system has led to gains in operational efficiency, consistency and safety, enabling operators to fracture a reservoir more hours/day compared to standard procedures and techniques.
Tim Marvel / SEF Energy Austin Johnson / Downing Phillip Douget / Blue Ox Resources Michael Mast / Blue Ox Resources John Dyer / SEF Energy Jordan Kuehn / SEF Energy Brian Wiesner / Downing

In 2018, the first framework for adding automation to a frac stack was proposed internally. The proposal called for adding sensors and automated controls to hydraulic valves with a live data stream and post job analytics. Shortly thereafter, a novel third-party technology was identified and acquired. Pairing the service company’s operational expertise with the automation expertise of the third party, an expansive vision formed to methodically eliminate the primary barriers to fracturing the reservoir 24/7.

These barriers, identified as: 1) the time between stages (this includes transition time and pressure tests); 2) downtime associated with gate valve maintenance and failures; 3) pump maintenance; and 4) sand and water logistics, would be eliminated through novel, fit-for-purpose products, automated workflows and integrated control systems.

A roadmap was established that emphasized continual system development and increased levels of automation, as each hurdle was overcome, Fig. 1. Similar to the roadmap used for autonomous vehicles, the hydraulic fracturing roadmap utilizes successive improvements and integrations to functions and subsystems to achieve ever higher levels of autonomy, safety and consistency. Table 1 describes each automation level and its impact on safety, consistency and pump efficiency.

Fig. 1. Roadmap to 24/7 hydraulic fracturing.
Fig. 1. Roadmap to 24/7 hydraulic fracturing.

The surface system currently has been integrated into a single subsystem, achieving Level 4 automation. This subsystem is integrated into the wireline and pump subsystems, laying the foundation to achieve Level 5. Contrast this with most operators using Level 2 surface systems that employ multiple, non-integrated controls, leaving most process control to checklists, procedures, and human expertise.

Automated surface system (Freedom Series Completion System) to achieve 24/7. Several papers have been published regarding the automated surface system in its initial phases. The automated surface system has the following components, with several of the recent upgrades highlighted for further details:

  • Base system 
    • Automated latch (Freedom Series Latch)
    • Automated valve (Freedom Series Valve) 
  • Automated valve controller (Freedom Series iControl)
    • Controls all gate valves.
    • Automates greasing of all valves on every actuation
    • Enables continuous pumping operations through automated valve transition while pumping.
    • New greasing algorithms ensure every valve receives the proper amount of grease, using only a fraction of the grease traditionally used.
    • Has led to multiple days of fracing the entire day at treatment pressure.
  • Automated lubricator 
    • Automates the pre-fill and equalization of the lubricator.
    • Includes patented automated vent sub technology and RFID technology.
  • Automated missile equalization 
    • Reduces time required to swap a pump by rapidly bleeding pressure down.
    • Accurately and quickly equalizes missile with the well.
    • Eliminates personnel entering red zone when bleeding missile pressure.
  • Automated pump swapping (Freedom Series Hot Swap)
    • Automates the process of replacing pumps without going into the red zone while pumping.

These system components are integrated into a single, automated surface system that enables an operator to instantaneously transition from one stage to the next continuously, day after day. The system eliminates the four barriers to pumping 24/7 through the following means:

  • The time between stages (this includes transition time and pressure tests)
    • The base system and the automated valve controller enable near-instantaneous valve transitions (less than 30 sec) while pumping.
  • Downtime associated with gate valve maintenance and failures.
    • The base system eliminates the need to use the stack to shut in for transition, utilizing the stack gate valves only when well shut-in is required.
    • Every time a valve is actuated, the system greases the valve with precisely the amount of grease required to fill the cavity, no more, no less. This is described in more detail in the AGA section. This method has drastically reduced repairs and failures.
  • Pump maintenance
    • The new automated pump swapping system enables a pump to be replaced without entering the red zone during pumping, eliminating the need to shut down the frac job to repair pumps. In addition, pumps can now be put on a preventative maintenance schedule, leading to more up time and less costly repairs per frac pump.
  • Sand and water logistics
    • Although the system does not directly address sand and water logistics, a system that leads to more consistent frac jobs aids in planning sand and water logistics.

An automated lubricator reduces decision time, as well as potential NPT events:

  • Automatically detects which lubricator is on which well. As the automated surface system leads to faster operations, with limited to no time between stages and with the introduction of simul-fracs, operators are choosing to utilize multiple wireline trucks on a job. To ensure the automated surface system knows which lubricator is on which well, RFID technology has been implemented to positively identify this relationship.
  • Once the lubricator is detected by RFID, the system automatically latches the lubricator, eliminating a human-interaction step in the process.
  • With a positive test completed, the system fills the lubricator until the new automated vent sub detects fluid. This is done to ensure all air is out of the lubricator, as today’s manual slobber lines or vent subs do not provide assurance air is eliminated from the lubricator, potentially leading to burnt wireline, due to adiabatic heating during the equalization process. In addition, the system has been engineered with two pumps, one to fill and the other to equalize pressure, with the fill-pump incapable of generating sufficient pressure to cause adiabatic heating. With these features, the automated vent sub eliminates burnt wireline as a concern.

Automated missile equalization. In many frac operations today, personnel enter the red zone to bleed off the missile. Integrated into the automated surface system is the bleed-down and equalization of the missile from the safety of the frac van, shortening the time required to switch out pumps and removing personnel from a hazardous red zone operation. This enables frac crews to always be completely red zone-free, eliminating the need for any exceptions. And it saves additional time and expense by automatically greasing the equalization plug valves, eliminating a potential source of NPT.

Automated pump swapping. The key remaining barrier is ensuring pumps are operational 24-hr/day to keep pumping at the prescribed rate. Today, the average frac crew utilizing zippers operates consistently at 16 hr/day, leaving a 50% upside in pumping each day when this problem is resolved. Figure 2 highlights the potential efficiency and utilization gains of employing the automated pump swapping technology.

Fig. 2. Efficiency opportunities, moving from traditional zipper operations to the automated surface system without, and then with, automated pump swapping.
Fig. 2. Efficiency opportunities, moving from traditional zipper operations to the automated surface system without, and then with, automated pump swapping.

The traditional approach to pump maintenance has focused on improvements to the pump truck. The automated pump swapping addition to the automated surface system approaches the problem differently by enabling a pump to be replaced without stopping operations or personnel entering the red zone. The system is placed between each frac pump and the missile. When a pump needs to be repaired or replaced, the system isolates the pump, bleeds down the pressure, and unlatches the pump. The pump truck is then removed out of the red zone to be repaired or replaced with another truck.

The repaired pump truck is backed into a set position, actuated arms couple the automated pump swapping skid with a hose plate mounted to the back of the truck, and the plates are clamped. A prime up-pressure test and equalization is performed before the pump is brought back online. Provided the benefits of the automated surface system, this additional technology enables an operator to achieve 24 hr of pumping per day. Benefits to the pumper include higher pump truck utilization, greater revenue, more frac jobs per month, and fewer trucks required on any given pad to maintain rate. A prototype was tested in July 2022, with eight pump swaps successfully completed without stopping the frac job, Figs. 3 and 4. Lessons learned from the prototype have been incorporated into the final product.

Fig. 3. First prototype of automated pump swapping skid
Fig. 3. First prototype of automated pump swapping skid
Fig. 4. First prototype of pump truck.
Fig. 4. First prototype of pump truck.

INDUSTRY FIRSTS

To achieve the goal of 24/7 fracturing required, a number of industry firsts are outlined below.

Self-equalizing automated valve. The base system, commercialized in 2019, automates the equalization process, enabling rapid transitions.

Remote, integrated latch. Part of the base system, the integrated latch is interlocked with the automated valve, eliminating potential pressure releases by ensuring the latch is properly tested and in place before the valve can actuate. In addition, the system allows the lubricator to be attached during frac, eliminating time on critical path for this task.

Digital handshake. A unique authentication code, changing every 30 sec, is tied to each person authorized to use the system. The digital handshake reduces the risk of NPT by ensuring the system is operated only by qualified personnel and provides traceability, if issues occur.

Remote hydraulic greasing. Other greasing systems traditionally use pneumatics to drive grease. Using hydraulics delivers a pressure curve, providing assurance of grease, eliminating greasing time as well as reducing valve-related NPT events.

Integration of the surface system. Traditional surface systems have multiple, non-integrated controls. For illustration, the typical surface system has separate controls for each valve, the greasing system, and the latch system. Process control is achieved through human-driven workflows, checklists, placards, lock-out/tag-out. Human-driven workflows are prone to error and, therefore, NPT. The Freedom Series completion system fully automates these sub-systems into an integrated system.

Continuous pumping well transitions. The first continuous pumping transition was conducted in October 2020, in the northeastern U.S. Continuous pumping is a process that reduces stage-to-stage transition time to seconds.

24-hr continuous pumping. This milestone was first achieved in September 2021 and represents the initial step toward continuous pumping 24/7.

Remote frac plan execution. The ability to execute the next well transition from a remote frac plan entered by the completion engineer, providing frac flexibility to the engineer, as well as ensuring the correct stage is completed. The system maintains a queue of fractured wells and will work through prescribed steps suggesting swaps in order of wireline activity or will pull from a stage list provided by a completion engineer. Either way, it will then remove the well from the available wells to frac until it sees wireline activity again. It eliminates the human decision factor when swapping, providing the ability to auto-swap as we progress to Level 5 automation.

Swapping a pump while treating. Demonstrated in July 2022.

Automated simulfrac transitions. In May 2022, the automated surface system was adapted to simulfrac operations, eliminating stage-to-stage time on simulfrac jobs.

Continuous pumping on a simulfrac job. In May 2022, the automated surface system transitioned from two wells to two separate wells, performing 11 valve actuations, and initiating greasing of each valve, all in under 40 sec, facilitating the opportunity to pump 24/7 on simulfrac operations.

WHY AUTOMATION?

The age-old debate that is generated when a new technology stands to replace current practice is well-documented. This same debate can be heard today within the frac community, relative to surface system automation. Historically, OFS has done manually what Downing (an SEF Energy company) does automatically (but have you done it every time), we need to work on all our issues before we take on a new system (SEF’s system removes many problems, so you can focus on other issues), our pumps cannot keep up, we have sand and water issues.

What is lost in the debate is that each issue masks another. If you have pump issues, this may be masking valve issues; supply issues may be masking pump issues. In addition, without the high-resolution data available, determining the root cause of an issue is often difficult and sometimes impossible. Process improvement involves systematically, eliminating an issue, and then focusing on the next issue to be resolved. Referring to the roadmap in Fig. 1, Level 0 to Level 3 automation involves human interaction between functions, requiring time-consuming processes, checklists, and personnel expertise. As noted, when issues inevitably occur, it is difficult to find the root cause with the disparate systems on pad.

As personnel change over time, process discipline and experience are lost, leading operators to again experience issues they thought they had resolved. Automated workflows found in Levels 4 and 5 are driven by one second of data capturing every system function. System data and automated workflows reduce non-productive time in two ways: 1) through real time alerts warning the operator of impending issues that need resolution; and 2) NPT-causing issues that occur are positively identified through root cause analysis and, unique to automation are engineered and/or programmed out, permanently eliminating that issue.

Figure 5 illustrates why automation is key to permanently eliminating issues. With the passage of time, the system becomes more robust, leading to faster and more consistent frac jobs. To illustrate this concept, the system initially used wellbore fluid to equalize through a ball valve and choke. Sand in the fluid caused wear on the ball valve. In addition, the choke had to be properly sized, based on well parameters. Identifying this as an opportunity for improvement, the ball valve was engineered out of the system, replaced by a boost pump and clean fluid to perform equalization and fill the lubricator.

Fig. 5. Benefits of choosing automated workflows over human-driven workflows
Fig. 5. Benefits of choosing automated workflows over human-driven workflows

ANALYTICS IMPROVE EFFICIENCY

The automated surface system generates gigabytes of data per job, tracking everything from pressures to valve positions, to open and close events. These data are used in real time for

lockouts, ensuring the system only operates when the prescribed conditions are present. In addition, the data are used for live and post-well analytics to improve operator performance. The data are also used for failure mode analysis, leading to new signatures for alerts identifying potential NPT. A few of the data applications are highlighted below.

Operational dashboard. Unique to the automated surface system, an operational dashboard (Fig. 6) provides the interface for the operator, onsite service personnel, and remote operations personnel to maintain the surface system, preventing NPT events prior to occurrence, as well as identifying improvement opportunities in real time. The dashboard trends operational data, provides real-time status of all systems, alerts personnel of both potential failures, as well as predictive maintenance events, and provides insight for operational improvements.

Fig. 6. Operational dashboard showing live automated surface system condition
Fig. 6. Operational dashboard showing live automated surface system condition

An adaptive grease algorithm (AGA) has been added recently to the automated surface system. The AGA was developed to ensure all gate valves are greased properly upon every actuation (defined as packing off the grease void with grease and then stopping), reducing grease and valve repair costs and eliminating premature valve failures. This both ensures the grease void is full for every actuation while also eliminating excess grease and subsequent issues associated with grease in the borehole.

Initial deployment occurred in October 2022 with striking results, Table 2. Pump strokes (correlated to the amount of grease consumed) to grease each zipper, pump down and stack valve were measured before and after implementation of the AGA. Overall, grease volume decreased by 55% across all valves (see adjacent table), with no detrimental effects to valve repairs or NPT. Subsequent application of the AGA has seen grease volume decrease by up to 90%.

Latch-to-latch (L2L) is calculated and plotted as a measure of wireline turnaround time, from the time of unlatching the wireline to when it is stabbed and latched again, Fig. 7. In addition to L2L, fill and drain times are also captured to the second.

Stage-to-Stage (S2S) time is defined at two locations: 1) the time between stages at a prescribed pressure (just under treatment pressure) and 2) at treatment pressure, Fig. 8. Stage-to-stage captures the white space between stages, consisting primarily of transition time, pressure test time, non-pump maintenance time, and ramp up/down of pressure and pump maintenance time. It also includes non-productive pumping (NPP) time, defined as time after a transition but before the frac is back at treatment pressure, not captured in traditional pump efficiency calculations. NPP includes time to ramp up pressure, pressure tests and spotting acid on critical path.

Fig. 7. Latch-to-latch times highlight wireline turnaround efficiency.
Fig. 7. Latch-to-latch times highlight wireline turnaround efficiency.
Fig. 8. Stage-to-Stage time calculation.
Fig. 8. Stage-to-Stage time calculation.

Stage-to-stage is a better indicator of job efficiency than pump efficiency. Pump efficiency suffers from several flaws that make it difficult to compare one job to another including the following:

Long vs short stages. Long stages artificially inflate pump efficiency. Comparing two frac jobs, one with long stages (e.g. 3 hr) the other with short stages (e.g. 1 hr), the longer stage job could be deemed more efficient, due to the operational cost of transitions on the shorter stages. This can give the false impression that one crew is better than another. As a side note, significantly reducing the operational cost of the transition with the automated surface system, provides completion engineers more flexibility when designing their treatment program (i.e. providing additional options for limited entry fracs through shorter stages).

Defined calculation. Pump efficiency is not captured in a consistent way from operator to operator or from pressure pumper to pressure pumper. This leads to errors comparing different crews, operators, or pressure pumpers.

Includes NPP (Non-Protective Pumping). Pump time is often started after the transition but before the pumper is back at treatment pressure. Recalling the goal to pump 24/7 at treatment pressure, transitioning is only one part of the time between stages. As noted above, the time between stages can also include NPP, slow ramp up times, and waiting. Not only does this provide a false measure of efficiency, but when charged by the pump hr, a job will cost more.

To compare the efficiency of one job to another, the S2S is plotted on a histogram ranging from 0.5 minutes (min.) to 60 min. between stages, Fig. 9. Stage-to-stage is plotted as a percentage of the total number of stages. For example, using Fig. 9, 28% in the 0.5-min. range signifies 28% of the stages were transitioned in less than 30 sec, representing continuous pumping operations (continuous pumping typically is in the 30-60 sec range). The 60-min. bucket was chosen as a cutoff, given anything over 60 min. indicates serious problems on the pad that can span days, unnecessarily skewing the S2S. This also is an indicator of the quality of a job, as a low percentage in the 60-min. bucket (<90%) indicates more problems than the typical pad.

Figure 10 highlights S2S plotted as an overall average time, with a 95% confidence interval showcasing transition consistency throughout the job. As noted, S2S over 60 min. has been removed, as larger issues, some lasting days, can skew what would otherwise be an excellent job.

Fig. 9. Stage-to-stage histogram documenting the efficiency of a job versus two benchmarks
Fig. 9. Stage-to-stage histogram documenting the efficiency of a job versus two benchmarks
Fig. 10. Average stage-to-stage time, 95% confidence interval of a job and two benchmarks.
Fig. 10. Average stage-to-stage time, 95% confidence interval of a job and two benchmarks.

ISIP

Although not a universal practice, many operators utilize ISIP to gauge the quality of each frac stage. Traditionally, this requires a well to be shut-in for a set period. An engineer selects several points on a screen to establish an ISIP number. There are several issues with this practice including: 1) requires up to 5 min. between stages in which operation is shut down; 2) requires time for an engineer to collect and then manually pick points on a pressure curve; and 3) can be inconsistent, based on the level of experience of the person calculating the ISIP.

The operator requested this process be automated from surface system data. They recognized that by utilizing the automated surface system, the ISIP could be calculated without operational or administrative cost. The system is open to each well the entire job, eliminating the need to stay on a specific well for minutes after the end of the stage waiting for the data to be captured. In addition, the lengthy ISIP data process includes downloading the data, plotting the data, and manually capturing the ISIP. This process was automated and is performed in real time by the automated surface system’s edge computers on the specific well, utilizing derivatives to capture ISIP. The ISIP is then streamed to the cloud, where the engineer can download the specific number for each stage.

To validate the results, an experienced engineer captured the ISIP data manually, using the “Superior ISIP” method and compared it to both the ISIP derived from the automated surface system as well as that supplied by the pumping company. Figure 11 highlights that the system-derived ISIP from the automated surface system and the superior ISIP match almost exactly, establishing the accuracy of the automated surface system ISIP calculation. The yellow ISIP points (collected from the pressure pumper) are obviously flawed by continuous pumping operations but also inherent inconsistencies of data collection at the human level.

Fig. 11. ISIP operator calculation (superior ISIP) vs automated ISIP vs pumper ISIP.
Fig. 11. ISIP operator calculation (superior ISIP) vs automated ISIP vs pumper ISIP.

CASE HISTORY 1

Blue Ox Resources, a private equity-backed Permian Delaware company based in Dallas, Texas, chose to employ the automated surface system after utilizing it with their former company, Primexx. Primexx was an early adopter of the automated surface system and has contributed insights to its development over the past three years. The system was chosen for its efficiency, the elimination of human error, interlocks that prevent deadheading or cutting wireline, and the inherent safety of the system through the removal of people from the red zone and the pad. With their previous experience, and employing the latest additions to the automated surface system, Blue Ox Resources set new efficiency records with the system on the El Duderino East and El Duderino West pads, Fig. 12.

Fig. 12. Stage-to-stage histogram showing the efficiency differences utilizing the automated surface  system.
Fig. 12. Stage-to-stage histogram showing the efficiency differences utilizing the automated surface system.

Located just south of Pecos, Texas, both El Duderino pads (Fig. 13) consisted of 3 wells each, spaced 200 ft apart, Fig. 14. The east pad comprised 130 total stages, with the west pad at 126 stages. Pump times averaged 110 min./stage (at treatment pressure), and 100 mesh sand was used. The stack configuration (manual valve, hydraulic valve, cross, with the base system on top of the cross) is 15k-rated. The zipper consists of two hydraulic valves, which are both actuated during the transition, providing a constant double barrier. The pressure pumper provided 22 Tier II pumps with 2007/2008 manufacturing dates.

Fig. 13. Blue Ox Resources&#x27; El Duderino pad.
Fig. 13. Blue Ox Resources' El Duderino pad.
Fig. 14. Operator 2 personnel working the automated surface system from the frac van.
Fig. 14. Operator 2 personnel working the automated surface system from the frac van.

To maintain rate, 16 pumps were required at any one time. The pressure pumper contract does not include any mandatory maintenance periods. The pressure pumper does have internal personnel incentives to pump more hr/day. The pressure pumper runs until they are down to 16 pumps, completing the stage they are on before shutdown. The operator then shuts down the pad, the non-operational pumps are repaired, and preventative maintenance is done on the other pumps. As soon as 18 to 20 pumps are ready, the frac job resumes.

Prior to the job, Blue Ox Resources required the surface system provider, wireline and pressure pumper representatives, along with the field operators, to meet to fully understand the automated surface system and how it operates. Expectations were set by Blue Ox Resources that at least 10 stages would be pumped each day, and continuous pumping would be done on every stage possible.

Utilizing the stage-to-stage times to accurately judge the performance, the Blue Ox Resources jobs were compared to the previous 15k record in the Delaware basin, Fig. 15. In September 2021, the first job to continually pump for 24 hr was recorded (with subsequent records set on the same pad at 35 hr), with the average S2S time for the job at 10 min., continuously pumping 50% of the stages.

Fig. 15. Operator 2 El Duderino results versus area benchmarks
Fig. 15. Operator 2 El Duderino results versus area benchmarks

In the same year, Operator 1’s Nimitz pad dropped the S2S average to 9.2 min. The average S2S for Operator 2’s two pads was lowered to 5.4 min. and 3.3 min, respectively, in December 2022, continuously pumping 70% of the stages. The 95% confidence interval also tightened with the latest Operator 2 jobs, documenting the consistency of the S2S. A job continuously pumped 24/7 would show 100% in the upper left-hand corner of Fig. 12. Both jobs pumped over 10.6 stages per day, with the El Duderino East achieving 10.7 stages per day.

CASE HISTORY 2

As noted above, the first version of the automated pump swapping system was tested in July 2022, with the test validating the coupling/decoupling sequences. Lessons learned from the first iteration were applied to the second prototype including:

  • Isolating pump vibrations within the skid.
  • Pump and missile agnostic connection system (i.e. system could be used with any pump or missile with only slight modifications).

The revised system was tested in late January 2022 on Operator 2’s Gutterballs State 14-15 pad. The system under test utilized a missile automation skid connected to the missile (automates the functionality of any missile) and two automated pump swapping skids each connected to a frac pump on one side and the missile on the other through the missile automation skid, Fig. 16.

Fig. 16. Automated pump swapping system configuration.
Fig. 16. Automated pump swapping system configuration.

Each frac pump was modified with a simple plate on the back of the truck mounted at a set location. This plate contains two subs for the pump’s high-pressure and low-pressure lines connected to the frac pump, Fig. 18. Adapted to any frac pump, this enables a frac pump of one manufacturer to be swapped with a frac pump from a second manufacturer. With each pump backed into the skid, a coupling sequence is run, securing the frac pump to the automated pump swapping skid. The suction and discharge valves are then opened, allowing the frac crew to run their normal pressure test routine on the initial rig-up, prior to the start of the frac job. The coupled pump and automated pump swapping skid can be seen in Fig. 17.

Fig. 17. Automated pump swapping skid (right) coupled with the pump (left)
Fig. 17. Automated pump swapping skid (right) coupled with the pump (left)
Fig. 18. Modified frac truck showing the plate with two subs.
Fig. 18. Modified frac truck showing the plate with two subs.

Multiple coupling and decoupling sequences were run with the pumps offline to verify the coupling sequences. Automated pump swapping while continuing to frac was then tested. This involved isolating the pump requiring repair, bleeding down the pump, and decoupling while the remaining pumps continue to frac. The pumps were then repaired outside the red zone, pulled back into the automated pump swapping skid, coupled, primed, pressure-tested, and equalized (suction and discharge lines are opened), bringing the pump back online while the remaining pumps continued to pump. This was done four times, with each test more rigorous than the prior test. Results of the four tests are shown in Table 3.

The two key lessons learned from the first iteration, making the system agnostic to the pump and missile, and isolating the pump vibration, were successfully integrated into the second version of the system. The system worked as intended and is being integrated into the automated surface system. The new automated pump swapping system is now in production and will be deployed as an integral part of the automated surface system.

CONCLUSIONS

An automated surface system, the Freedom Series Completion System, has been developed to systematically eliminate the primary barriers to fracturing the reservoir 24/7. With the integration of the frac and wireline systems into the automated surface system, the system has successfully pumped continuously for multiple days on multiple pads. The final hurdle to 24/7 fracturing was to eliminate pump maintenance as a barrier. With the advent of automated pump swapping, this barrier has been eliminated. The system is now in place to achieve continuous 24/7 fracturing operations and with ongoing development, the automated surface system is nearing Level 5 automation.

ACKNOWLEDGEMENTS

The authors would like to thank ProFrac for their help testing the second iteration of the automated pump swapping system. Also, thanks go to Liberty Energy and Steward Energy for their help testing the first iteration of the system. This article contains excerpts from SPE paper 213101-MS, “Automated completion surface system: The path to fracturing 24/7,” presented at the SPE Oklahoma City Oil and Gas Symposium, held at the Oklahoma City Convention Center, April 17-19, 2023.

About the Authors
Tim Marvel
SEF Energy
Tim Marvel is V.P. business development and technology at SEF Energy. Prior to joining SEF Energy, he served in a variety of domestic and international executive roles at Baker Hughes, Alcoa and Dover. Mr. Marvel graduated from Colorado School of Mines with a BS degree in mechanical engineering and is a licensed professional engineer in the state of Texas. He holds 21 patents and has co-authored nine technical and trade journal articles.
Austin Johnson
Downing
Austin Johnson is V.P. completions for Downing. Prior to joining Downing, he served in a variety of operations and managerial roles at Oil States and owned a business at the start of his career. He specializes in completion optimization and his expertise has played a critical role in the development of automated completion systems. Mr. Johnson holds multiple patents for automated completion technologies.
Phillip Douget
Blue Ox Resources
Phillip Douget is V.P. and general manager of the Permian basin for Blue Ox Resources. Prior to Blue Ox, he served as manager of integrated service planning and manager of midstream at Primexx. In those roles he managed $1 billion of capital investments and oversaw the buildout of the Primexx gas and water infrastructure in the Delaware basin. He began his career at Halliburton holding various roles in drilling, completions and water management. Mr. Douget graduated with a BA degree from Northwestern State University.
Michael Mast
Blue Ox Resources
Michael Mast is V.P. of engineering for Blue Ox Resources. Prior to Blue Ox, he served as subsurface engineering manager at Primexx. He began his career with Halliburton holding various engineering roles ultimately ending his time as a member of their technical team. Mr. Mast graduated from Rose-Hulman Institute of Technology with a BS degree in chemical engineering.
John Dyer
SEF Energy
John Dyer works to develop automated equipment for completions at SEF Energy. He has also applied his expertise in the areas of cardiac electrophysiology, aviation and navigation and airborne weather radar. His main research interests are in instrumentation and measurement, data acquisition and signal processing of acquired data. Dr. Dyer holds a BS in physiology from Oklahoma State University, in addition to BS and MS degrees and a PhD in electrical engineering from the University of Oklahoma. He has taught junior and senior level classes in electrical engineering and developed a graduate course in statistical digital signal processing.
Jordan Kuehn
SEF Energy
Jordan Kuehn is focused on designing the control system for the Freedom Series automated completion system for SEF Energy. He started his career with the Colex Group, designing and building automated end-of-line test systems for aerospace, defense and energy companies. Mr. Kuehn received a BS degree in computer engineering with a focus in digital signal processing in 2009 and a MS degree in electrical and computer engineering in 2010, both from the University of Oklahoma. He holds one patent.
Brian Wiesner
Downing
Brian Wiesner is president of surface systems at SEF Energy, which is comprised of the Downing brand. He joined SEF in 2015 after 20 years in various technical, management and international positions at Baker Hughes, FMC Technologies and GE Oil & Gas. Mr. Wiesner holds a BS degree in engineering from the Colorado School of Mines and an MBA from both Cornell University and Queen’s University.
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