introduction: excessive temperature rise during drilling of the mandible for dental implant placement might damage adjacent osseous tissues. various factors affect temperature rise, including the geometrical parameters of surgical drills, one of which is the drill bit head angle. the aim of this research was to determine suitable drill bit head angle to induce minimum temperature rise during ma...

Drill mud is a fluid which is used in oil extraction industries in order to cool and lubricate the drill bit. Due to containing numerous toxic components, it is considered as a hazardous waste which must be treated before discharging to the environment. Current separation techniques for drill cutting treatment can be categorized into three main categories of physical (dewatering), physiochemica...

Spatially regulated transcription of the pipe gene in ventral cells of the Drosophila ovary follicle cell epithelium is a key event that specifies progeny embryo dorsal-ventral (DV) polarity. pipe encodes ten putative protein isoforms, all of which exhibit similarity to vertebrate glycosaminoglycan-modifying enzymes. Expression of one of the isoforms, Pipe-ST2, in follicle cells has previously ...

A study is presented of a miniature ultrasonic surgical drill designed for bone biopsy, based on an ultrasonic/sonic drill which converts high frequency to low frequency vibrations through a freely vibrating mass between an ultrasonic transducer-horn and a drill bit. For conventional surgical drilling using a rotary drill or an ultrasonic drill, considerable power is required to penetrate into ...

NGH (natural gas hydrate) is a sort of green energy with huge reserves. When drilling and exploiting NGH, the complex environment will aggravate vibration drill string, which destroy stability reservoir make it decompose to produce large amount gas. Gas flows into annular fluid, filling gas–liquid two-phase flow variation in characteristic parameters pipe flow. The mixed string more intense. In...

This paper presents a novel pneumatic Down-The-Hole (DTH) hammer with self-rotation bit used for rock drilling, and the mechanical structure working principle are mainly covered. A unique mechanism ratchet pawl incorporated in DTH is proposed percussion-rotation drilling to break rock. The drill can rotate while pipe stays still because of design reduces friction between borehole. Firstly, rati...