scholarly journals Wear Analysis of gun barrel drill blade in 1.0503 steel drilling process in Milpro HG12 oil environment with addition of ultra-dispersive copper particles and copper oxides

2020 ◽  
Author(s):  
Kazimierz Rychlik ◽  
Cezary Senderowski

The paper presents construction solutions for guiding a single-sharp barrel drill blade during drilling deep holes, with an analysis of construction and technological problems for two ways of inserting the drill into the processed material in the first stage of drilling - using a pilot hole or guide sleeve. During the implementation of the technological process of deep drilling of holes with barrel drills using a vertical numerical milling machine FNE 40NC AVIA, the kinematics of the object-tool system (P-N) and other technological parameters affecting the execution of pilot holes in strictly defined technological operations were analyzed. The course of operational tests carried out using two types of cooling-lubricating agents - Milpro HG12 oil without and with the addition of ultra-dispersive copper particles and copper oxides (0.05 ÷ 0.6 µm), Panther GP-1 (PWPH PantherOil Poland) in a ratio of 1 to 100 is characterized. Based on the performed drilling of through holes in 1.0503 steel with EB80 drills with a diameter Dc = 8 mm, made of cemented carbide K15 (WC 94%, Co 6%), the course of wear of the barrel drill blade on the total drilling path Lw = 8000 mm for 112 was determined through holes and Kw geometric wear indicator of the drill bit. The obtained results of wear were compared with the results of tribological tests. with the use of cooling lubricants, under the conditions of friction involving 1.0503 steel with tungsten carbide, of chemical composition as K15. The material and technological conditions of abrasive wear of a particular friction pair are the same as for operational tests of the barrel drill blade wear at deep hole drilling.

Author(s):  
M. M. Okasha ◽  
P. T. Mativenga ◽  
L. Li

Mechanical microdrilling of nickel-based aerospace alloys suffers from premature drill breakage due to the fragile nature of the microdrill. Additionally, burr size reduction in both macro- and microscales has become one of the key problems in the drilling process. This paper presents a new method to microdrill Inconel 718 alloy using laser followed by mechanical drilling (sequential drilling). The aim of this research was to understand and evaluate the capability of using sequential laser mechanical drilling method as an effective and efficient method in drilling difficult-to-cut metals. Two new approaches were developed, namely, a two-step process of laser pilot drilling followed by twist drilling and a three-step process of laser pilot hole drilling followed by mechanical pilot drilling and then twist drilling. The holes produced by the new approaches were compared with those by mechanical microdrilling (pilot drilling and then twisting drilling). The results show that mechanical drilling eliminates the laser drilling defects. Furthermore, while large nonuniform burrs with attached cap were found in pure mechanical drilling, 75% reduction in burr size was achieved with the complimentary sequential drilling technology. Additionally, when compared with purely mechanical microdrilling, the new drilling method resulted in 240–430% tool life increase. Thus, the new drilling method presents an opportunity for industry to extend tool life and decrease burr.


2018 ◽  
Vol 108 (01-02) ◽  
pp. 76-80
Author(s):  
S. Michel ◽  
D. Prof. Biermann

Tiefbohrungen erfordern bei anspruchsvollen Anbohrsituationen speziell angepasste Bohrbuchsen oder eine mehrstufige Prozesskette aus Planfräsen, Pilotbohren und Tiefbohren. Mit einem hybriden Maschinenkonzept, bestehend aus einem Laser und einer konventionellen Tiefbohreinheit, lässt sich die Prozesskette deutlich verkürzen. Im Rahmen dieses Artikels wird der Laserpilotbohrprozess für den Edelstahl 1.4404 untersucht und die Verfahrenskombination bei mehreren Anbohrsituationen umgesetzt.   Deep hole drilling requires special drill bushes or a multi-stage process chain of face milling, pilot hole drilling and deep hole drilling for demanding surface geometries. With a hybrid machine concept, consisting of a laser and a conventional deep hole drilling unit, the process chain can be significantly shortened. Within the scope of this article, the laser pilot hole drilling process for AISI 316L is investigated and the process combination for several surface geometries is implemented.


2019 ◽  
Vol 3 (2) ◽  
pp. 111-118
Author(s):  
Bahtiar Wilantara ◽  
Raharjo Raharjo

This study aims to develop an analog compression tester measuring instrument into a digital compression tester as a measurement tool that can provide effectiveness and efficiency to users.                     This research is a research and development or R&D. This research was conducted in several steps, namely: problem identification, information gathering, product design, product manufacture, expert validation, product revision, testing, final production. The development of analog compression tester was first validated by material experts, media experts, and 15 students, and 5 students for field trials. The subjects of this study were vocational students at Taman Karya Madya Teknik Kebumen. Data collection techniques used in this study using instruments in the form of a questionnaire. The data analysis technique of this research is descriptive qualitative and quantitative descriptive percentage.                 The results of the development of digital compression tester designs are: 1) the tools and materials used are electric drill, grinding, cutter, goggles, gloves, masks, ruler, acetaminine welding, screwdriver, scissors, digital dial pressure gauge, hose, spark plugs, clamps , and nepel, 2) the manufacturing process that starts from the cutting process, the hole drilling process, the welding process and the process of connecting between components, 3) the workings of digital compression tester design that is reading the pressure or compression of the machine displayed on the monitor digitally using dial pressure digital gauge, 4) the test results obtained from the validation results from: a) material experts at 89% or Eligible; b) media experts at 85% or reasonable; c) response of field trial students in terms of ease of use and reading of 90% or feasible. Thus, the conclusion that the digital compression tester measuring instrument declared feasible to use for measurement.


2020 ◽  
Vol 87 (12) ◽  
pp. 757-767
Author(s):  
Robert Wegert ◽  
Vinzenz Guski ◽  
Hans-Christian Möhring ◽  
Siegfried Schmauder

AbstractThe surface quality and the subsurface properties such as hardness, residual stresses and grain size of a drill hole are dependent on the cutting parameters of the single lip deep hole drilling process and therefore on the thermomechanical as-is state in the cutting zone and in the contact zone between the guide pads and the drill hole surface. In this contribution, the main objectives are the in-process measurement of the thermal as-is state in the subsurface of a drilling hole by means of thermocouples as well as the feed force and drilling torque evaluation. FE simulation results to verify the investigations and to predict the thermomechanical conditions in the cutting zone are presented as well. The work is part of an interdisciplinary research project in the framework of the priority program “Surface Conditioning in Machining Processes” (SPP 2086) of the German Research Foundation (DFG).This contribution provides an overview of the effects of cutting parameters, cooling lubrication and including wear on the thermal conditions in the subsurface and mechanical loads during this machining process. At first, a test set up for the in-process temperature measurement will be presented with the execution as well as the analysis of the resulting temperature, feed force and drilling torque during drilling a 42CrMo4 steel. Furthermore, the results of process simulations and the validation of this applied FE approach with measured quantities are presented.


2005 ◽  
Vol 127 (2) ◽  
pp. 271-276 ◽  
Author(s):  
D. N. Dilley ◽  
D. A. Stephenson ◽  
P. V. Bayly ◽  
A. J. Schaut

Drill chatter degrades hole roundness, hole size, and tool life. This wastes time and money in tools, scrap, and hole rework. Chatter prediction in milling and turning has shown significant benefit to industry; however, researchers have been unable to accurately predict chatter in drilling applications. In the past, the drill, including the chisel edge, was modeled as either a fixed-fixed or fixed-pinned beam (Tekinalp, O., and Ulsoy, A. G., 1989, “Modeling and Finite Element Analysis of Drill Bit Vibrations,” ASME J. Eng. Indust. 111, pp. 148–154), but more recent research (Dilley, D. N., Bayly, P. V., and Schaut, A. J., 2005, “Effects of the Chisel Edge on the Chatter Frequency in Drilling,” J. Sound Vib., 281, pp. 423–428) has shown that a fixed-embedded model using springs improves frequency matching. The effects of the drill margins on dynamics have not been studied. The fixed-fixed or fixed-pinned model will be shown to be inappropriate for modeling the effects of margin engagement, while the spring-end boundary condition can better approximate the frequency increase observed experimentally as the drill margins engage deeper into the hole. In addition, the shifted frequency is well below the frequency found from an analytical fixed-fixed or fixed-pinned beam. Evidence that the margins cause the frequency shift is seen in three-dimensional waterfall plots that show this shift for pilot hole drilling (in which the margins are engaged), but not for tube drilling (in which margins are not engaged).


Author(s):  
Aditya Thadani ◽  
Athamaram H. Soni

Abstract Experimental and theoretical research data was utilized in building a Fuzzy Logic Controller model applied to simulate the drilling process of composite materials. The objective is to have a better understanding and control of delamination of composites during the drilling process and at the same time to improve the hole finish by controlling fraying and splintering. By controlling the main issues in the drilling process such as feed rate, cutting speed, thrust force, and torque generated in addition to the tool geometry, it is possible to optimize the drilling process avoiding the conventionally encountered problems.


2022 ◽  
Vol 6 (1) ◽  
pp. 7
Author(s):  
Menghui Zhu ◽  
Chao Wei ◽  
Wei Guo ◽  
Zhizhou Zhang ◽  
Jinglei Ouyang ◽  
...  

Although laser drilling of carbon fibre-reinforced polymer (CFRP) composites offers the advantages of zero tool-wear and avoidance of fibre delamination compared with mechanical drilling, it consumes considerably more energy during the drilling process. This research shows that by using a new, stepped parameter parallel ring laser hole drilling method, an energy saving of 78.10% and an 18.37 gCO2 reduction for each hole, while improving productivity by more than 300%, can be achieved in laser drilling of 6 mm diameter holes in CFRP sheets of 2 mm in thickness, compared with previous laser drilling methods under the same drilling quality. The key reason for this is an increase in energy input to the inner rings enabling more rapid removal of the material, while the lower energy input for the outer ring provides a shielding trench to reduce the heat loss into the parent material. The results are compared with single-ring laser drilling and multiple-ring laser drilling with constant processing parameters, and a discussion is given on comparing with mechanical drilling and future prospects, including a combined mechanical drilling and laser pre-scribing process.


10.29007/72d4 ◽  
2018 ◽  
Author(s):  
He Liu ◽  
Edouard Auvinet ◽  
Joshua Giles ◽  
Ferdinando Rodriguez Y Baena

Computer Aided Surgery (CAS) is helpful, but it clutters an already overcrowded operating theatre, and tends to disrupt the workflow of conventional surgery. In order to provide seamless computer assistance with improved immersion and a more natural surgical workflow, we propose an augmented-reality based navigation system for CAS. Here, we choose to focus on the proximal femoral anatomy, which we register to a plan by processing depth information of the surgical site captured by a commercial depth camera. Intra-operative three-dimensional surgical guidance is then provided to the surgeon through a commercial augmented reality headset, to drill a pilot hole in the femoral head, so that the user can perform the operation without additional physical guides. The user can interact intuitively with the system by simple gestures and voice commands, resulting in a more natural workflow. To assess the surgical accuracy of the proposed setup, 30 experiments of pilot hole drilling were performed on femur phantoms. The position and the orientation of the drilled guide holes were measured and compared with the preoperative plan, and the mean errors were within 2mm and 2°, results which are in line with commercial computer assisted orthopedic systems today.


Procedia CIRP ◽  
2021 ◽  
Vol 104 ◽  
pp. 1924-1929
Author(s):  
Yue Si ◽  
Xuyang Li ◽  
Lingfei Kong ◽  
Jianming Zhen ◽  
Yan Li

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