A study on modeling and grinding for twist drill flank

2014 ◽  
Author(s):  
Chun Du ◽  
Zezhong Chen ◽  
Liming Wang
Keyword(s):  
Twist Drill

Hyperthermia catheter implantation and therapy in the brain

1990 ◽  
Vol 72 (6) ◽  
pp. 975-979 ◽  
Author(s):  
J. Alexander Marchosky ◽  
Christopher J. Moran ◽  
Neal E. Fearnot ◽  
Charles F. Babbs
Keyword(s):  
Computerized Tomography ◽  
Malignant Gliomas ◽  
Twist Drill ◽  
Ct Scanner ◽  
Tumor Blood Flow ◽  
Content Type ◽  
Catheter Implantation ◽  
Computer Controlled ◽  
Drill Holes ◽  
The Brain

✓ For the treatment of malignant gliomas, a technique for implanting hyperthermia catheters was developed that utilized a stereotactic template and head-stabilization frame mounted on a computerized tomography (CT) scanner. Computerized tomography scans were used to measure tumor dimensions and to determine the number, implantation depths, and active heating lengths of the catheters, which were implanted through twist-drill holes while the patient was in the CT room. Heat was subsequently delivered via implanted catheters using a computer-controlled hyperthermia system, which partially compensates for heterogeneous and time-varying tumor blood flow.

scholarly journals Effect of Twist Drill Geometry and Drilling Parameters on Hole Quality in Single-Shot Drilling of CFRP/Al7075-T6 Composite Stack

2021 ◽  
Vol 5 (7) ◽  
pp. 189
Author(s):  
Muhammad Hafiz Hassan ◽  
Jamaluddin Abdullah ◽  
Gérald Franz ◽  
Chim Yi Shen ◽  
Reza Mahmoodian
Keyword(s):  
Feed Rate ◽  
Thrust Force ◽  
Critical Dimension ◽  
Helix Angle ◽  
Single Shot ◽  
Twist Drill ◽  
Hole Quality ◽  
Drilling Parameters ◽  
Industry Practice ◽  
Maximum Thrust

Drilling two different materials in a layer, or stack-up, is being practiced widely in the aerospace industry to minimize critical dimension mismatch and error in the subsequent assembly process, but the compatibility of the drill to compensate the widely differing properties of composite is still a major challenge to the industry. In this paper, the effect of customized twist drill geometry and drilling parameters are being investigated based on the thrust force signature generated during the drilling of CFRP/Al7075-T6. Based on ANOVA, it is found that the maximum thrust force for both CFRP and Al7075-T6 are highly dependent on the feed rate. Through the analysis of maximum thrust force, supported by hole diameter error, hole surface roughness, and chip formation, it is found that the optimum tool parameters selection includes a helix angle of 30°, primary clearance angle of 6°, point angle of 130°, chisel edge angle of 30°, speed of 2600 rev/min and feed rate of 0.05 mm/rev. The optimum parameters obtained in this study are benchmarked against existing industry practice of the capability to produce higher hole quality and efficiency, which is set at 2600 rev/min for speed and 0.1 mm/rev for feed rate.

scholarly journals Chronic subdural hematoma: a systematic review and meta-analysis of surgical procedures

2014 ◽  
Vol 121 (3) ◽  
pp. 665-673 ◽  
Author(s):  
Weiming Liu ◽  
Nicolaas A. Bakker ◽  
Rob J. M. Groen
Keyword(s):  
Outcome Measures ◽  
Surgical Procedures ◽  
Subdural Hematoma ◽  
Meta Analysis ◽  
Chronic Subdural Hematoma ◽  
Controlled Trials ◽  
Cochrane Central Register ◽  
Twist Drill ◽  
Recurrence Rates ◽  
Postoperative Drainage

Object In this paper the authors systematically evaluate the results of different surgical procedures for chronic subdural hematoma (CSDH). Methods The MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and other databases were scrutinized according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) statement, after which only randomized controlled trials (RCTs) and quasi-RCTs were included. At least 2 different neurosurgical procedures in the management of chronic subdural hematoma (CSDH) had to be evaluated. Included studies were assessed for the risk of bias. Recurrence rates, complications, and outcome including mortality were taken as outcome measures. Statistical heterogeneity in each meta-analysis was assessed using the T2 (tau-squared), I2, and chi-square tests. The DerSimonian-Laird method was used to calculate the summary estimates using the fixed-effect model in meta-analysis. Results Of the 297 studies identified, 19 RCTs were included. Of them, 7 studies evaluated the use of postoperative drainage, of which the meta-analysis showed a pooled OR of 0.36 (95% CI 0.21–0.60; p < 0.001) in favor of drainage. Four studies compared twist drill and bur hole procedures. No significant differences between the 2 methods were present, but heterogeneity was considered to be significant. Three studies directly compared the use of irrigation before drainage. A fixed-effects meta-analysis showed a pooled OR of 0.49 (95% CI 0.21–1.14; p = 0.10) in favor of irrigation. Two studies evaluated postoperative posture. The available data did not reveal a significant advantage in favor of the postoperative supine posture. Regarding positioning of the catheter used for drainage, it was shown that a frontal catheter led to a better outcome. One study compared duration of drainage, showing that 48 hours of drainage was as effective as 96 hours of drainage. Conclusions Postoperative drainage has the advantage of reducing recurrence without increasing complications. The use of a bur hole or twist drill does not seem to make any significant difference in recurrence rates or other outcome measures. It seems that irrigation may lead to a better outcome. These results may lead to more standardized procedures.

Emergency frontal twist drill ventriculostomy

1970 ◽  
Vol 33 (2) ◽  
pp. 226-227 ◽  
Author(s):  
Gary E. Kaufmann ◽  
Kemp Clark
Keyword(s):  
Twist Drill

scholarly journals Machinability Study of Hybrid Nanoclay-Glass Fibre Reinforced Polyester Composites

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
P. Prabhu ◽  
P. Jawahar ◽  
M. Balasubramanian ◽  
T. P. Mohan
Keyword(s):  
Tool Wear ◽  
Glass Fibre ◽  
Microstructural Analysis ◽  
Process Parameter ◽  
Optimum Process ◽  
Machining Parameters ◽  
Twist Drill ◽  
End Mill ◽  
Glass Fibre Reinforced ◽  
Polyester Composites

Glass fibre reinforced polyester composites (GRP) and hybrid nanoclay and glass fibre reinforced polyester nanocomposites (CGRP) are fabricated by vacuum assisted resin infusion technique. The optimum mechanical properties are obtained for CGRP with 3 wt.% nanoclay. Three types of drills (carbide twist drill D 5407060, HSS twist drill BS-328, and HSS end mill (4 flutes “N”-type end mill RH-helical flute)) of 6 mm diameters are used to drill holes on GRP and CGRP. Three different speeds (600, 852, and 1260 rpm) and two different feeds (0.045, 0.1 mm/rev) are selected as process parameters. The effect of process parameter on thrust force and delamination during drilling CGRP is analyzed for optimizing the machining parameters. The delamination factor is low for the optimum process parameter (feed = 0.1 mm/rev and speed 852 rpm). Microstructural analysis confirms that at higher feeds, delamination is low for CGRP drilled with carbide tools. In order to analyze the effect of nanoclay in CGRP on tool wear, 200 holes were drilled on CGRP samples with 3 wt.% nanoclay, and the tool wear is analyzed under optimized parametric condition. Tool wear is high in HSS twist drill compared with carbide drill. The presence of nanoclay also accelerates the tool wear.

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