Results 41 to 50 of about 69,267 (280)
Predicting remaining lifetime of drill pipes basing upon the fatigue crack kinetics within a pre-critical period [PDF]
, 2019 Purpose is to determine regularities of the development of corrosive fatigue cracks in terms of high-strength drill pipes. Methods. Basing upon the approaches of the material failure mechanics, the crack has been characterized by the area that is the ...
Moisyshyn, V, Tyrlych, V
core +1 more source
Fluid Mechanics of the Drilling String [PDF]
Journal of Petroleum Technology, 1953 To help field men select the proper nozzle and pump liner size, a pocket calculator has been designed which will predict the performance of the hydraulic system. Although the use of the drilling fluid to control and condition the hole is well known, the present use of high jet velocities has brought purely hydraulic problems to much ...
openaire +1 more source
Advanced Science, EarlyView.A biomimetic, fiber‐reinforced hydrogel (FE‐PDA@Fib/Gel‐TG) that enables dual‐phase cranial defect repair. The system provides: instant hemostasis in the early stage, and sustained co‐delivery of pro‐angiogenic and osteogenic signals for synergistic vascularized bone regeneration.
Lingbin Che +9 more
wiley +1 more source
Nonlinear Static Analysis of Riserless Sampling Drill String in Ultra-deepwater of South China Sea
Shiyou jixie, 2017 With the load effects of current, wave, soil, drifting of drill ship during the sampling drilling process, the rope type drill string has very complex static characteristics featuring geometric nonlinearity and contact nonlinearity.
Gao Guanghai +4 more
doaj
Suppression of Stick-Slip Vibration of Drill String by Fractional-Order PID Control
Shiyou jixie, 2020 Stick-slip vibration of drill string is one of the important reasons leading to accelerated wear and premature damage of drilling equipment, reduced drilling safety and reduced drilling efficiency.
Zhang Qizhi, Xu Shuai
doaj
A Novel Mesoscopic Drill Bit Model for Deep Drilling Applications
Modelling, 2023 This paper deals with the development of a novel mesoscopic model of polycrystalline diamond compact (PDC) drill bits that can be implemented in complex drill string models for simulations to analyse the influence of rock inhomogeneities or the impact of
Mohamed Ichaoui +2 more
doaj +1 more source
British Educational Research Journal, EarlyView.Abstract Quality in early childhood education and care (ECEC) is a contested concept and has generally been conceptualised by inter‐related indicators such as staff qualifications, educational environment, policy or child‐to‐staff ratios. There has been a more limited emphasis on how young children might perceive and experience quality.
Nikki Fairchild, Éva Mikuska
wiley +1 more source
Analysis of Transverse Vibration of the Drill String in Vertical Section of Horizontal Well
Shiyou jixie, 2017 For the drill string fatigue failure caused by drill string resonance, taking the drill string in the vertical section of a horizontal well in the southwest of China as study object, the inner and outer pressure of the drill string as the function of ...
Cao Yu +5 more
doaj
Analysis of vibration efficiency of drill string using the theory of random vibrations [PDF]
, 2013 The paper presents the main results of the research work related to the development of theoretical and experimental methods for assessment of vibration strength level of the drill string components using probability theory.
Hohol, V. I. +2 more
core
British Educational Research Journal, EarlyView.Abstract Cooperative learning is a widely adopted teaching method to improve academic achievement. This review synthesises existing research on the use of cooperative learning within a school setting for pupils aged 11–16 years. Such a review has not been undertaken to date and will present an evidence base for educators considering implementation ...
Patricia Hampson +2 more
wiley +1 more source