Ulterra推出的TorkBuster工具能够大幅提高钻进效率，改善作业效果！
编译 | TOM 惊蛰
Ulterra公司利用其专利技术开发了TorkBuster工具，是业内唯一一种能够直接对钻头施加扭冲的钻井工具。如同冲击式驱动器，TorkBuster将液压能转换为扭冲，使具有攻击性的PDC钻头能够在更深的切削深度下破碎、钻穿最坚硬的岩石。此外，破碎岩石效率提高可避免发生粘滑，在破碎过程中，钻杆扭转能周期性的存储与释放。这意味着，不仅可以钻的更快，而且钻头与底部钻具组合可钻的更久。
在钻井行业中，粘滑现象引起了广泛关注。当使用聚晶金刚石复合片（PDC）固定切削齿钻头钻硬地层时，钻头粘滑是常见问题。在最佳的钻井条件下，PDC钻头在固定的切削深度(DOC)下剪切地层。当钻遇较硬的地层时，钻头无法吃入地层，必须增加钻压(WOB)使PDC的切削齿吃入地层。然而，很多时候不能立即克服地层的反扭矩，在这种情况下，钻头会减速或停止(卡住)，同时扭矩储存在钻柱中，直到达到破碎地层所需的扭矩，钻头会发生剧烈旋转(滑脱)。这种作用会对PDC切削齿与其他钻柱组件造成损坏，从而导致钻头与切削齿寿命缩短，机械钻速（ROP）降低。
减轻粘滑现象的传统方法包括：调整作业参数以避免粘滑；采用切削齿更多、背斜角更大的PDC钻头；选用破岩效率低的牙轮钻头或镶金刚石钻头。这些方法收效甚微，还降低了整体钻进效率，并降低了机械钻速。
在TorkBuster内部，配置了一个旋转的冲击锤与锤座，泵入的钻井液流经该工具时会驱动冲击锤，产生低水平的扭冲，传递到独立的钻头驱动短节。该工具以高频扭冲的形式直接向钻头输送额外的能量。钻进转速与钻压通过TorkBuster外壳传送到钻头上，外壳采用了槽状驱动结构。扭冲被独立传输到钻头的驱动短节。因此，槽顶断面隔离了额外的能量，使其不再向上传递。如果TorkBuster停止工作，它将成为BHA的惰性组件。无需停止钻进或将其起出井眼，钻头可继续转动并向前钻进。
TorkBuster可在多数钻井应用中体现自身的价值。然而，业内通常认为这些应用由于一些原因，在力学与动力学方面存在功能障碍。这可能是马达质量差、钻柱小或轻、泥浆比重过高、以及其他应用，难以将稳定的钻压与扭矩传递给PDC钻头。在某些情况下，这些应用是通过继续使用牙轮钻头或镶金刚石钻头来确定的。
性能提高
Ulterra公司致力于通过使用高端的钢材与PDC钻头胎体，以及创新型应用技术，最大限度地提高油气钻井作业的效率。在世界各地的钻井区块中，我们凭借久经考验的性能建立了良好的声誉。每一次的下入，我们都能向您展示如何提高钻井效率并降低成本。
地层阈值为破碎地层所需的扭矩与传递至BHA的反扭矩，如果地层阈值变化不规律，反扭矩变得不稳定，会导致BHA的不稳定与粘滑。TorkBuster扭冲为TorkBuster提供的高频扭转能量，能够在不增加传递到BHA的反扭矩的情况下，钻更高的地层阈值。使用TorkBuster，反扭矩可以平稳地传递到BHA中，减少振动与粘滑，TorkBuster适用于6in（152毫米）至9.875in（250毫米）的井眼。
对于澳大利亚中部的油气公司而言，Ulterra公司的CounterForce与TorkBuster是最佳搭档。一家油气公司最近通过将Ulterra公司的TorkBuster与U513M CounterForce钻头相结合，节省了大量时间与成本。Ulterra公司的防粘滑扭冲工具TorkBuster，可缩短作业时间，保证钻头使用寿命，减少为更换钻头而进行起下钻作业。
事实证明，TorkBuster与CounterForce的组合可应对具有挑战性的Permian地层，作业者将机械钻速提高了52％，总共节省了15万美元。TorkBuster减少了钻头相关的扭矩与粘滑问题，大幅提高了钻井作业效率。从作业者那儿获得反馈都是正面的，包括：稳定性更高；减少了粘滑；BHA所受反扭矩更稳定；延长钻头使用寿命；提高机械钻速；扩展钻头的限程；增强定向控制。
CounterForce是Ulterra的PDC钻头技术，采用独特的切削齿配置来降低钻头反扭矩与振动。与传统的PDC钻头不同，切削齿同时工作以降低横向振动并增加裂缝扩展。CounterForce切削结构设计用于切割岩石，同时可保持更一致的扭矩，从而提高稳定性与机械钻速。
技术优势?
- 提高钻头性能，降低钻井成本；
- 可有效替代牙轮钻头；
- 更具攻击性的PDC钻头；
- 提高钻硬地层的机械钻速；
- 更少的起下钻，可延长PDC钻头使用寿命；
- 避免粘滑造成的损伤可延长BHA的使用寿命；
- 在定向井中可加强工具面的控制。
Ulterra’s patented TorkBuster tool is the only drilling tool that adds a torsional impact directly to the drill bit. Just like an impact driver, the TorkBuster converts hydraulic energy into torsional hammering action that enables aggressive PDC bits to fracture and drill through even the hardest rock at higher depths of cut. Also, failing the rock more frequently prevents stick-slip, a destructive process where torsional energy is cyclically stored up and released from the drill string. That means that not only do you drill faster, but your bit and BHA stay drilling longer.
The phenomenon of stick-slip is well researched and documented within the drilling industry. Bit-related stick-slip is often a problem when drilling hard formations with a Polycrystalline Diamond Compact (PDC) fixed-cutter bit. Under optimum drilling conditions, the PDC bit shears formation with a constant depth of cut (DOC). When a harder formation is encountered the bit loses DOC and more weight-on-bit (WOB) must be added to engage the PDC cutters in formation. Many times, however, the reactive torque of the formation cannot be overcome immediately – in this case the bit slows or stops (stick) while torque is stored in the drill string until the torque required to fail formation is achieved and the bit violently rotates (slip). This action can cause damage to PDC cutters and other drill string components, resulting in reduced bit and tool life as well as poor rate of penetration (ROP).
Traditional methods for mitigating stick-slip involve adjusting operating parameters to avoid the stick-slip phase, pacifying the PDC bit by using higher blade counts, higher backrakes, etc., or even by using less-efficient roller cone or diamond-impregnated bits. These methods have only been marginally successful and reduce overall drilling efficiency and lead to reduced potential ROP.
Inside TorkBuster a rotating hammer and anvil assembly – driven by drilling fluid pumped through the tool – creates low level torsional impacts that are transferred to an independent bit drive sub. This mechanism delivers additional energy directly to the bit in the form of high frequency torsional impulses. Drilling RPM and WOB is transmitted to the bit via the TorkBuster housing which utilizes a castellated drive mechanism. Torsional impulse is transmitted independently to the bit drive sub. The castle section therefore isolates the additional energy from travelling back up the string. In the event the TorkBuster ceases to function, it becomes an inert component of the BHA. There is no need to stop drilling or pull out of hole as the bit will continue to turn and drill ahead.
Drilling applications where the TorkBuster adds value range across a broad spectrum. However, they are usually identified where drilling mechanics and dynamics are known to be dysfunctional for some reason. This may be poor motor quality, small or lightweight drill string, extremely high mud weight, and other applications where it has become difficult to transfer consistent weight and torque to the PDC bit. In some cases these applications are identified by the continued use of roller cones or diamond impregnated bits.
Ulterra’s unique TorkBuster tool dramatically reduces bit related torque and stick-slip problems adding significant efficiency to drilling operations.
Ulterra is dedicated to maximizing the efficiency of oil and gas drilling operations through the use of cutting edge steel and matrix PDC bits and innovative application technologies. Throughout the world’s drilling basins we are building our reputation on proven performance. When every run counts, let us show you how we can improve your drilling efficiencies and lower your costs.
Ulterra CounterForce? and TorkBuster? a Winning Combination for Major Operator in Central Australia A major operator in central Australia recently achieved significant time and cost savings thanks to the combination of the Ulterra TorkBuster matched with the U513M CounterForce drill bit. The TorkBuster – Ulterra’s anti stick-slip torsional impact tool – reduces drilling time, preserves bit life and saves a bit trip.
The combination of TorkBuster and CounterForce proved to be a rock destruction solution within the challenging Permian, with the operator increasing ROP by 52% and achieving total savings of $150,000.
The Tools in Detail
TorkBuster reduces bit-related torque and stick-slip problems, adding significant efficiency to drilling operations. The feedback received form operators includes improved stability and reduced stick-slip; smoother reactive torque in BHA; improved bit life and ROP; extended bit range and enhanced directional control.
CounterForce is Ulterra’s PDC drill bit technology that uses a unique cutter configuration to lower bit reactive torque and vibration. Unlike traditional PDC bits, the cutters work together to lower lateral vibration and increase crack propagation. The CounterForce cutting structure is engineered to slice through rock while maintaining a more consistent torque signature, thus increasing stability and ROP.