Vibration Technologies for Friction Reduction to Overcome Weight Transfer Challenge in Horizontal Wells Using a Multiscale Friction Model

We have replaced the periodic Prandtl–Tomlinson model with an atomic-scale friction model with a random roughness term describing the surface roughness of micro-electromechanical systems (MEMS) devices with sliding surfaces. This new model is shown to exhibit the same features as previously reported experimental MEMS friction loop data. The correlation function of the surface roughness is shown to play a critical role in the modelling. It is experimentally obtained by probing the sidewall surfaces of a MEMS device flipped upright in on-chip hinges with an AFM (atomic force microscope). The addition of a modulation term to the model allows us to also simulate the effect of vibration-induced friction reduction (normal-force modulation), as a function of both vibration amplitude and frequency. The results obtained agree very well with measurement data reported previously.

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Vibration-induced nanoscale friction modulation on piezoelectric materials

Friction ◽

10.1007/s40544-021-0552-y ◽

2022 ◽

Author(s):

Jiawei Cao ◽

Qunyang Li

Keyword(s):

Piezoelectric Materials ◽

Effective Means ◽

Mechanical Vibration ◽

Friction Model ◽

Friction Reduction ◽

Small Scale ◽

Vibrational Amplitude ◽

Vibration Source ◽

Reduction Effect ◽

Piezoelectric Thin Film

AbstractMechanical vibration, as an alternative of application of solid/liquid lubricants, has been an effective means to modulate friction at the macroscale. Recently, atomic force microscopy (AFM) experiments and model simulations also suggest a similar vibration-induced friction reduction effect for nanoscale contact interfaces, although an additional external vibration source is typically needed to excite the system. Here, by introducing a piezoelectric thin film along the contact interface, we demonstrate that friction measured by a conductive AFM probe can be significantly reduced (more than 70%) when an alternating current (AC) voltage is applied. Such real-time friction modulation is achieved owing to the localized nanoscale vibration originating from the intrinsic inverse piezoelectric effect, and is applicable for various material combinations. Assisted by analysis with the Prandtl—Tomlinson (P—T) friction model, our experimental results suggest that there exists an approximately linear correlation between the vibrational amplitude and the relative factor for perturbation of sliding energy corrugation. This work offers a viable strategy for realizing active friction modulation for small-scale interfaces without the need of additional vibration source or global excitation that may adversely impact device functionalities.

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A feasible model for friction-reduction investigation of drillstrings in long-horizontal wells with axial oscillation tools and analysis of key influencing factors

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2019.106643 ◽

2020 ◽

Vol 185 ◽

pp. 106643

Author(s):

Jianxun Liu ◽

Hualin Zheng ◽

Yuchun Kuang ◽

Bin Yu ◽

Yang Zhou ◽

...

Keyword(s):

Influencing Factors ◽

Horizontal Wells ◽

Friction Reduction ◽

Axial Oscillation

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Modelling of Friction Phenomena Existed in Drawbead in Sheet Metal Forming

Materials ◽

10.3390/ma14195887 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5887

Author(s):

Tomasz Trzepieciński ◽

Andrzej Kubit ◽

Romuald Fejkiel ◽

Łukasz Chodoła ◽

Daniel Ficek ◽

...

Keyword(s):

Sheet Metal ◽

Sheet Metal Forming ◽

Metal Forming ◽

Rolling Direction ◽

Back Propagation ◽

Experimental Tests ◽

Friction Model ◽

Friction Reduction ◽

Training Algorithms ◽

Sheet Rolling

The article presents the results of friction tests of a 0.8 mm-thick DC04 deep-drawing quality steel sheet. A special friction simulator was used in the tests, reflecting friction conditions occurring while pulling a sheet strip through a drawbead in sheet metal forming. The variable parameters in the experimental tests were as follows: surface roughness of countersamples, lubrication conditions, sample orientation in relation to the sheet rolling direction as well as the sample width and height of the drawbead. Due to many factors that affect the value of the coefficient of friction coefficient, artificial neural networks (ANNs) were used to build and analyse the friction model. Four training algorithms were used to train the ANNs: back propagation, conjugate gradients, quasi-Newton and Levenberg–Marquardt. It was found that for all analysed friction conditions and sheet strip widths, increasing the drawbead height increases the COF value. The chlorine-based Heavy Draw 1150 compound provides a more effective friction reduction compared to a LAN-46 machine oil.

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Drag-Reduction Performance Evaluation of Controllable Hybrid Steering Drilling System

Shock and Vibration ◽

10.1155/2021/6688656 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Jianyan Zou ◽

Ping Chen ◽

Tianshou Ma ◽

Yang Liu ◽

Xingming Wang

Keyword(s):

High Efficiency ◽

Vertical Section ◽

Drilling Fluid ◽

Horizontal Wells ◽

Friction Reduction ◽

Drilling Process ◽

Drag Torque ◽

Horizontal Section ◽

Drilling System ◽

Friction Reducing

The excessive drag/torque and the backing pressure is an important factor that restricts the improvement of the penetration rate and the extension of the drilling in the sliding drilling process of extended-reach wells and horizontal wells. To deal with this problem, this paper developed a novel controllable hybrid steering drilling system (CHSDS) based on the friction-reducing principle of a rotating drill string. The CHSDS is composed of a gear clutch, hydraulic system, and measurement and control system. By controlling the meshing and separation of the clutch with the mud pulse signal, the CHSDS has two working states, which leads to two boundary conditions. Combined with the stiff-string drag torque model, the effects of the drilling parameters on the friction-reducing performance of the CHSDS are analyzed systematically. The results show that the friction reduction effect in the inclined section is the most significant, followed by that in the horizontal section, whereas there is almost no impact in the vertical section. Friction reduction increases with the rotary speed and the drilling fluid density, whereas it decreases with the increase in the surface weight-on-bit and the bit reaction torque. Field tests confirm the separation and meshing function of the CHSDS. The developed controllable hybrid steering and friction-reducing technology provides an alternative approach for the safe and high-efficiency drilling of horizontal wells.

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