In this paper, we present three methods to achieve reliable drillbit angular velocity control for deep drilling operations. We consider a multi-sectional system with the bit off-bottom, which represents at start-up of operation, e.g., after connection. The procedures are all based on distributed model system. proposed has been field validated and considers Coulomb friction between drillstring b...

Safe and efficient deep drilling is a fundamental requirement for the development of oil gas resources. In this regard, application membrane separation technology fluid monitoring highly significant. study, several commonly used permeable materials were analyzed, PDMS was preliminarily selected as suitable material downhole separation. We designed an experimental setup to investigate performanc...

To improve the service life of newly designed pneumatic downhole motor, a kind commercially available lithium complex grease was used to help avoid rapid wear-induced failure dynamic seal tools in operation. The investigation on tribological behaviors QBe2 beryllium bronze and 38CrMoAlA steel tribo-pairs motor revealed that under lubrication, instantaneous friction coefficient wear volume becam...

We study the traffic of two types of molecular motors using the two-species asymmetric simple exclusion process (ASEP) with periodic boundary conditions and with attachment and detachment of particles. We determine characteristic properties such as motor densities and currents by simulations and analytical calculations. For motors with different unbinding probabilities, mean-field theory gives ...

Increasing drilling speed and shortening the well construction period are goals of field. The use downhole speed-up tools has been noted for its advantages such as no additional cost, change in equipment impact on normal operations. However, conventional cannot meet needs when drilled formation contains hydrogen sulfide. Then, technology test increasing by absorption hydraulic supercharging dri...

Abstract Vibro-impact drilling has shown huge potential of delivering better rate penetration, improved tools lifespan and borehole stability. However, being resonantly instigated, the technique requires a continuous quantitative characterisation drill-bit encountered rock materials in order to maintain optimal performance. The present paper introduces non-conventional method for downhole using...

A Fracture Modeling System has been developed by Electric Power Development Company (EPDC) to facilitate the interpretation, display and analysis of fractures identified by borehole imaging tools. Borehole images of individual fractures provide understanding of the local properties of the fracture itself. If an integrated model of the field’s large-scale fracture system could be developed, it w...

We consider a class of systems influenced by perturbations that are nonlinearly parameterized by unknown constant parameters, and develop a method for estimating the unknown parameters. The method applies to systems where the states are available for measurement, and perturbations with the property that an exponentially stable estimate of the unknown parameters can be obtained if the whole pert...