Results 21 to 30 of about 213 (157)
CREATION OF PORTABLE DOWNHOLE HAMMERS FOR ROTARY-PERCUSSIVE DRILLING OF BOREHOLES
Interexpo GEO-Siberia, 2021 This paper presents the design of portable downhole hammers for borehole diameters of 43 and 76 mm when drilling with a combined rotary-percussive method in coal mines. The scope of use is described. Features and advantages of prototypes are shown. The characteristics of DHH and research data are given.
Sergey E. Alexeev +2 more
openaire +1 more source
Study on Construction Technology of Rock-socketed Pile Group for Offshore Wind Turbine Generators
Renmin Zhujiang, 2020 This paper simulates and analyzes the driveability of steel pipe pile under complex geological conditions by the GRLWEAP software,and studies the construction technology of integrated rock-socketed pile group based on the statistical analysis of the ...
CHENG Zishuo
doaj
The Sanitization of the Night: Gentrification and the Everyday Temporal Politics in Belgrade
City &Society, Volume 38, Issue 2, August 2026.ABSTRACT Urban scholarship increasingly recognizes that processes such as gentrification unfold not only through spatial transformations, but through shifts in sensory environments and everyday rhythms. In this paper, drawing on twenty‐three months of fieldwork in Belgrade, I examine how urban redevelopment (re)organizes time for middle‐class people ...
Alexandra Dantzer
wiley +1 more source
Clinical Case Reports, Volume 14, Issue 7, July 2026.ABSTRACT A standardized static‐guided framework integrating CBCT and intraoral scanning provides predictable, minimally invasive management for diverse intracanal obstructions. This unified digital workflow ensures precise root canal localisation in severe obliteration and conservative retrieval of fractured fiber or ultra‐hard posterior zirconia posts
Xinxuan Wang, Xuguang Li, Baicheng Yi
wiley +1 more source
A Stepwise Approach to Managing Bilateral Maxillary Sinus Tracts: A Case Report
Clinical Case Reports, Volume 14, Issue 7, July 2026.ABSTRACT This case report describes a rare presentation of bilateral intraoral sinus tracts of odontogenic origin associated with a maxillary right first molar (Universal #3). A key diagnostic challenge was differentiating an endodontic infection from vertical root fracture (VRF) in a previously treated tooth; no J‐shaped probing defect was detected ...
Ali Chamani +3 more
wiley +1 more source
Designed and Testing of the Positive Displacement Motor Driven Rotary Percussion Drilling Device
Shiyou jixie, 2016 The stability and service life of common rotary percussion drilling downhole tool is influenced by poor working conditions and is far from the field requirement. In view of this,a PDM driven drill string reciprocating percussion concept has been proposed,
Ma Guangjun +2 more
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AerospaceThe objective of the kinematic model of rock chips is to examine the impact of the driving parameters of drilling tools on the effective chip removal speed, with a view to analyze the chip removal performance of rotary percussion ultrasonic drilling. The
Yinchao Wang +6 more
doaj +1 more source
Use of the Rotary-Percussion Drilling Technology in the OKR Mining Conditions and by Drilling the Wells for Purposes of Heating Pump Installation [PDF]
Acta Montanistica Slovaca, 2004 Sedimentary rocks in the Ostrava-Karviná Coalfield (OKR) especially the Saddle Seams of the Karviná Formation are marked with considerable abrasive property following from the high content of siliceous component in these rocks.
Koníèek Jiøí, Mazáè Josef
doaj
Coral reef and mangrove interplay during Holocene sea level changes, Belitung Island, Indonesia
Earth Surface Processes and Landforms, Volume 51, Issue 7, July 2026.The fate of mangroves and coral reefs during the ongoing sea level rise depends not only on our ability to preserve the ecosystems but also on their geological preconditioning. Therefore, strategies to preserve mangrove ecosystems, while undoubtedly essential, wecan only be successful if accounting for their geological history. Abstract Coral reefs and
Tubagus Solihuddin +11 more
wiley +1 more source
Analysis and Improvement of the Rotary Percussion Drilling Tool in Oil Wells [PDF]
Proceedings of the 2015 International Symposium on Material, Energy and Environment Engineering, 2015 Experience over the few years has proved that rotary percussion technology is an effective method to improve the rate of penetration in drilling petroleum wells. The drilling speed of the rotary percussion drilling is about forty percent larger than the common drilling.
Huaigang Hu +2 more
openaire +1 more source