ESTMZ 系统概念起源于 2000 年代中期，旨在提高性能范围并进一步推动已经经过现场验证的 HAL STMZ 系统的操作简单性。这个新系统专门解决了墨西哥湾 (GoM) 下第三纪不断增长的需求。经过大量的概念开发、规划和研究，哈里伯顿推进了系统设计和制造，并进行了多次系统集成测试和全面的现场试验。

然后，在 2012 年夏天，哈里伯顿在下第三系安装了第一个商业 ESTMZ 系统。现在，大约 10 年后，墨西哥湾总产量的 10% 以上是通过哈里伯顿设计、制造和安装的完井系统生产的（图 1）。

下第三系共安装了 36 个 Xtreme 单行程多区 (XSTMZ) 和 ESTMZ 完井装置，包括裸眼 ESTMZ、套管井 XSTMZ 和裸眼 XSTMZ 配置，总计 133 个单独区域。迄今为止，运营商已向下第三系注入了超过 7000 万磅支撑剂，通过这些系统进行压裂和刺激生产。处理量和速率是专门为每口井设计的，泵速率从 15 到 45 bpm 不等。迄今为止，单个区域放置最多支撑剂的记录为 954,000 磅，但受到地层的限制。在一次单独作业中，使用单一维修工具在一次完井中泵送了令人难以置信的 306.3 万磅支撑剂。井眼轨迹通常是垂直或接近垂直的，这些系统安装的最大偏差略高于 50 度。系统长度从约 450 英尺到 3,200 英尺不等，各个区域长度从 42 英尺到 240 英尺不等。这些完井的安装测量深度 (MD) 范围从约 26,000 英尺到超过 31,000 英尺。

随着这些油田的成熟，某些产油层段的地层压力损耗对传统完井方法提出了挑战。必须正确管理枯竭层段的流体损失，同时保持对高压层段的良好控制，以防止井眼塌陷。人们很快就认识到，枯竭将带来独特的挑战。一旦无法再有效地管理射孔后的流体损失，就显然需要采取不同的方法。通过将更深的低压枯竭区与上方的高压产油区分开，并使用叠加版本的 ESTMZ 系统完成油井，可以满足这一需求。堆叠系统可以更好地控制射孔后的油井和滤失问题，同时保持单行程系统的固有优势。 

随着层状储层继续以不同的速度耗尽，人们意识到需要更强大的解决方案。除了管理流体损失之外，还需要考虑在枯竭区和原始压力区安装的封隔器和设备的不同额定值。原来的额定压力设备限制了最大表面处理压力，以防止井下工具系统过压。治疗压力的这种限制可能会对治疗方案产生不利影响，从而影响最终的生产。也许一个鲜为人知的考虑因素是减少完井反向输出阶段可施加的允许压力量。在这种情况下，显着受限的最大反向排出压力会阻碍操作灵活性，并降低在最坏情况下反向时的成功概率，例如工作管柱柱充满沙子的硬出沙。完井深度和下第三系固有的静水压力进一步加剧了这些挑战。为了更好地解决这些问题，哈里伯顿开发了 XSTMZ 系统，将系统额定值在 300 F 下提高到 15,000 psi。

也许在最初的系统开发过程中没有得到充分认识，XSTMZ 和 ESTMZ 完井所实现的效率还可以通过节省海上操作时间和优化压裂和供应船的利用率，显着减少运营商在整个运营过程中的碳足迹（图2），从而提供了显着的系统优势。 

XSTMZ 和 ESTMZ 系统专门为满足下第三系油井的完井要求而设计，对墨西哥湾的完井方式和石油产量产生了巨大影响。通过与客户密切合作并倾听行业的需求，哈里伯顿继续提供产品、专业知识和服务质量，以应对墨西哥低第三产业及其他地区所面临的严峻挑战。

The ESTMZ system concept originated in the mid-2000s to increase the performance envelope and drive further operational simplicity of the already field-proven HAL STMZ system. This new system specifically addressed the increasing demands of the Gulf of Mexico (GoM) Lower Tertiary. After considerable concept development, planning and research, Halliburton moved forward with system design and manufacture leading up to several system integration tests and full-scale field trials.

Then, in the summer of 2012, Halliburton installed the first commercial ESTMZ system completion in the Lower Tertiary. Now, some 10 years later, more than 10% of the total production output in the GoM is being produced through the completion systems that Halliburton designed, manufactured, and installed (Figure 1).

A total of 36 Xtreme Single-Trip Multizone (XSTMZ) and ESTMZ completions—made up of openhole ESTMZ, cased hole XSTMZ and openhole XSTMZ configurations—have been installed in the Lower Tertiary, amounting to 133 individual zones. To date, operators have injected over 70 million lb of proppant into the Lower Tertiary to frac and stimulate production through these systems. Treatment volumes and rates are designed specifically for each well, with pump rates varying from 15 to 45 bpm. The record for the most proppant placed in a single zone to date is 954,000 lb, which was limited by the formation. During a separate operation, an incredible 3.063 million lb of proppant was pumped using a single service tool in one completion. Wellbore trajectories are typically vertical or near-vertical, with the greatest deviation into which these systems have been installed being just above 50 degrees. System lengths vary from about 450 to 3,200 ft, with individual zone lengths ranging from 42 to 240 ft. Installed measured depths (MD) of these completions range from about 26,000 to more than 31,000 ft.

As these fields mature, formation pressure depletion in some pay intervals has challenged conventional completion methods. Fluid losses to the depleted intervals, while maintaining well control of the higher-pressure intervals, must be managed correctly to prevent wellbore collapse. It was soon understood that depletion would present a distinct and unique challenge. Once fluid losses after perforating could no longer be managed effectively, the need for a different approach became evident. This need was addressed by separating the deeper lower-pressure depleted zones from the higher-pressure pay zones above and completing the well with a stacked version of the ESTMZ system. Stacking the systems allowed for better control of the well and fluid loss issues after perforating while maintaining the inherent benefits of single-trip systems. 

As the layered reservoirs continued to deplete at varying rates, it was realized that a more robust solution would be necessary. In addition to managing fluid losses, the differential ratings of the packers and equipment installed across depleted and virgin pressured zones required consideration. The original pressure-rated equipment limited the maximum surface treating pressure to prevent over pressuring of the downhole tool system. Such limitations in treating pressure can adversely affect the treatment regimen and thus the resulting production. Perhaps a lesser-known consideration is the reduction in the allowable amount of pressure that can be applied during the reverse out stage of the completion. In this scenario, a significantly constrained maximum reverse out pressure can hinder operations flexibility and reduce the probability of success when reversing out in a worst-case scenario, such as a hard sandout with a work string column full of sand. Completion depths and hydrostatic pressures inherent to the Lower Tertiary further exacerbates these challenges. To better address these issues, Halliburton developed the XSTMZ system, bolstering the system rating to 15,000 psi at 300 F.

Perhaps not fully appreciated during initial system development, the efficiencies achieved with the XSTMZ and ESTMZ completions also allow for a significant reduction in the operators’ carbon footprint throughout the entire operation by saving operational time offshore and optimizing utilization of frac and supply vessels (Figure 2), thus offering a notable systems advantage. 

Specifically designed to meet the completion requirements of wells in the Lower Tertiary, the XSTMZ and ESTMZ systems are making a resounding impact on the way that completions are performed in the GoM and the volume of oil that is produced. By working closely with our clients and listening to the industry’s needs, Halliburton continues to deliver products, expertise and service quality to meet the critical challenges observed in the GoM Lower Tertiary and beyond.