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1

Porównanie sił instalacyjnych rurociągów z polietylenu

Griffiths Chelsea, Faghih Ashkan

Inżynieria Bezwykopowa

|

2023

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nr 3

76--81

PL

W niniejszym artykule porównane zostaną szacunkowe siły estymowane metodą ASTM i metodą PRCI z rzeczywistymi siłami zarejestrowanymi podczas instalacji rurociagów polietylenowych. W niniejszym dokumencie dla uproszczenia stosowany będzie skrót PE (polietylen). Należy zauważyć, że porównanie to ma dotyczyć zarówno instalacji MDPE jak i HDPE. Celem tego porównania jest określenie najdokładniejszej metodologii obliczeń dla instalacji rurociagów wykonanych z polietylenu.

2

Optimum combination of machining parameters during drilling of aluminium 7075 alloys using Grey based Taguchi approach

Sreenivasulu Reddy, Rao Chalamalasetti Srinivasa

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 3

227--238

EN

From ancient days to till today manufacturing industries, especially making of holes on the parts during drilling process for precision assembling of parts facing problems with burr formation. Drilling operation is one of the finishing operation in the production cycle, removing of burrs during drilling process is a time consuming and non-value added process to the manufacturing sector. So reducing the size of burrs is the main aim of the present study. In the present work, optimization of burr size is considered during drilling of aluminium 7075 alloy. In this connection, experiments are conducted based on Grey based Taguchi. From Grey relational grades of responses selected optimal combination of parameters to attain multiple performance characteristics of responses with a corresponding higher grey relational grade. For identifying the most significant input parameters that influence the output responses ANOVA is conducted. Based on interaction effect plots of data means of responses from results of ANOVA, confirmation tests are conducted by choosing most significant parameters. Finally, observations reveals that feed rate, point and clearance angles are the most influential factors on burr size and also experimental results divulge that the lower the thrust force causes to decrease the burr height. The proposed approach is helpful to the budding entrepreneurs in the related areas to select optimal combination of drilling parameters to attain multiple performance characteristics of responses especially in burr size to prevent the post finishing operations up to certain extent.

3

Surface integrity of machined surface in simultaneous cutting of CFRP

Shimana Kenji, Kawano Ryota, Harada Masakazu, Yoshimitsu Shinichi, Kobaru Yuya, Kondo Eiji

Journal of Machine Engineering

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2020

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Vol. 20, No. 1

98--106

EN

Carbon fiber-reinforced plastic (CFRP), a carbon fiber composite material, has high specific strength and stiffness, and has attracted attention as a structural material for transport machines from the viewpoint of improving fuel efficiency through weight reduction. However, the exiting CFRP processing methods have several disadvantages such as high cost, tool wear due to formation of hard chips during cutting, and occurrence of delamination that degrades machining accuracy. These limitations impede the practical application of CFRP. The purpose of this study is to propose a low cost and high precision drilling method “simultaneous cutting” by stacking the different materials with CFRP. Until now, high precision hole drilling has been studied by stacking titanium on CFRP. Because CFRP and titanium parts are joined by bolts in aircraft and so on. However, in this study, an inexpensive and easy to obtain acrylic resin plate was selected as a stacking material to focus on CFRP hole drilling. On the other hand, acrylic resin plate was used for CFRP hole drilling as a waste material. As a result, it was found that the thrust force was reduced by drilling the hole with stacking CFRP between two acrylic resin plates. Furthermore, the occurrence of delamination was suppressed at both the entry and exit sides of the hole.

4

Predictive modeling and machining performance optimization during drilling of polymer nanocomposites reinforced by graphene oxide/carbon fiber

Kumar Jogendra, Verma Rajesh Kumar, Mondal Arpan Kumar

Archive of Mechanical Engineering

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2020

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LXVII, nr 2

229--258

EN

This paper explores the parametric appraisal and machining performance optimization during drilling of polymer nanocomposites reinforced by graphene oxide/-carbon fiber. The consequences of drilling parameters like cutting velocity, feed, and weight % of graphene oxide on machining responses, namely surface roughness, thrust force, torque, delamination (In/Out) has been investigated. An integrated approach of a Combined Quality Loss concept, Weighted Principal Component Analysis (WPCA), and Taguchi theory is proposed for the evaluation of drilling efficiency. Response surface methodology was employed for drilling of samples using the titanium aluminum nitride tool. WPCA is used for aggregation of multi-response into a single objective function. Analysis of variance reveals that cutting velocity is the most influential factor trailed by feed and weight % of graphene oxide. The proposed approach predicts the outcomes of the developed model for an optimal set of parameters. It has been validated by a confirmatory test, which shows a satisfactory agreement with the actual data. The lower feed plays a vital role in surface finishing. At lower feed, the development of the defect and cracks are found less with an improved surface finish. The proposed module demonstrates the feasibility of controlling quality and productivity factors.

5

Evaluation of the thrust force of a multirotor agricultural drone

Berner B., Chojnacki J.

Journal of Research and Applications in Agricultural Engineering

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2018

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Vol. 63, nr 3

6--8

EN

Multirotor drones can be used in ecological agriculture as agricultural machines that do not produce pollution or knead the soil. The movement of drone over plants is related to the thrust generated by rotors and propellers. Test stand, where the drone was placed on electronic scales, was constructed in order to establish the thrust force of the drone. The test stand, where the drone was placed on electronic scales, was constructed in order to establish the thrust force of the drone. Optical tachometer was used to measure the propellers’ rotational speed. A mathematical formula was determined that describes the relation between the rotational speed of the drone propellers and the thrust force it generates.

PL

Drony wielowirnikowe mogą być wykorzystywane w rolnictwie ekologicznym jako maszyny rolnicze, które nie emitują zanieczyszczeń i nie ugniatają gleby. Ruch drona nad roślinami związany jest z wytwarzaną siłą ciągu przez wirniki i śmigła. W celu wyznaczenia siły ciągu drona zbudowano stanowisko badawcze, w którym dron osadzono na wadze elektronicznej, a do pomiaru prędkości obrotowej śmigieł użyto tachometru optycznego. Wyznaczono formułę matematyczną opisującą zależność pomiędzy prędkością obrotową śmigieł drona a wytwarzaną przez niego siłą ciągu.

6

Experimental Investigation of Process Parameters in Drilling LM25 Composites Coated with Multi Wall Carbon Nano Tubes Using Sonication Process

Sangeetha M., Prakash S.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 3

1761--1770

EN

Aluminium based metal matrix composites are widely used in automobile components such as cardan shaft of Chevrolet corvette, disc brake and engine push rod. In this experiment a Hybrid Metal Matrix Composites (HMMC) are fabricated and drilled. Drilling is the process of making slots in disc brake and thread in the engine parts. The surface quality of the drilled specimen depends on the speed, feed, drill type and the thrust force. Thrust force plays the major role in drilling the specimen. In this experiment HMMCs are fabricated using two processes-called, sonication and casting. Sonication is the process of coating the carbon nanotubes over the silicon carbide particles (SiCp). Semisolid stir casting is used to reinforce the coated SiCp in the LM 25 alloy. A drilling process is performed on HMMC to analyse the extent to which the input parameters influence the thrust force and Ovality. The tools used for drilling are solid carbide tools of three different diameters. Taguchi’s experimental design is adopted for the drilling operation. A mathematical model is used to determine the influence of input parameters on the outputs thrust force and ovality. This paper proves the combination of N3 , f1 and d1 of the carbide tool results in the lowest value of thrust force and ovality while drilling HMMCs. In this work the HMMC is prepared by coating the abrasive nature, silicon carbide particle and there is a good interfacial bonding between the reinforced particle and matrix and the drilling process becomes smoother. The new being of this article is the treated ceramics, SiCp with carbon nanotubes. This HMMC shows the improved mechanical properties compared to other metal matrix composites surveyed in the literatures.

7

A systematic analysis of the friction losses on bearings of modern turbocharger

Vanhaelst R., Kheir A., Czajka J.

Combustion Engines

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2016

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R. 55, nr 1

22--31

EN

In the article, a novel test rig for determining the friction losses of modern turbocharger is presented. The friction torque of the bearing of turbocharger can be measured direct and stationary at any speed up to 100,000 min–1 by the friction test rig developed by the Ostfalia, University of Applied Science (UAS). Since 2010, over 50 turbochargers were measured on the test bench in extensive measurement series. The results give valuable and new insights of the influence of the next parameters on the bearing friction losses: oil temperature, oil pressure, thrust force and oil flow rate. Furthermore, a comparison between the different bearing types (semi-floating, full floating and ball bearings) was performed. The main observations and results are discussed in the scientific article.

8

Analysis of Effect of Pulse Generated by the Special Object 12,7mm Equipped in Magnetorheological Damping System on the Thoracic Spine

Bajkowski M., Floiriańczyk A.

Machine Dynamics Research

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2013

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Vol. 37, No. 1

5-14

EN

The aim of this study was to perform comparative analysis of a rifle shot loads in the thoracic spine region for different shooting positions (prone and standing). This effect is related to the action of high energy pulse coming from a special object, equipped with a 12.7mm magnetorheological (MR) damping system. In numerical simulations the results of measurement of thrust force as a function of time for the system employing the principle of a short barrel recoil was used. Performed for different values of pulse numerical analysis helped to determine how thrust forces, arising from the movement of system, impact on the anatomical structures of the thoracic spine, and to indicate the optimal shooting position and dumping parameters taking into account the formation of the human spine injuries

9

Analityczny model samochodowej bezstopniowej przekładni cięgnowej

Bieniek A.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

|

2005

|

z. 80

17-29

PL

W opracowaniu sformułowano analityczny model bezstopniowej przekładni samochodowej. Wykorzystując podstawowe zależności geometryczne wyprowadzono wzory na wymaganą wartość siły naporu w kołach przekładni. Określono również w sposób analityczny wartość ilorazu sił naporu zależnie od chwilowej wartości przełożenia przekładni i doprowadzanego momentu obrotowego.

EN

In this paper the mathematical model of continuously variable transmission has been formulated. Using the approximate geometrical relations, the formulas for demanded thrust force have been derived. Also on the analytical way the thrust ratio as a function of transmission ratio and input torąue has been determined. The computing results have been compared with the experimental results.

10

Thrust vectoring in high-manoeuvrability aircraft

Błachnio J.

Systems : journal of transdisciplinary systems science

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2004

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Vol. 9, Sp. 2/1

38-50

EN

The paper has been intended to discuss the present-day trends in the field of developing the jet engine's thrust control concepts using various design solutions. What has been described is thrust control by means of additional flaps (jet tabs), rectangular nozzle as well as rotational and segmented axisymmetric nozzles. The output of research projects, with various solutions in the field of dirust control in high-manoeuvrability military aircraft applied, has also been presented.

PL

W artykule przedstawiono kierunki rozwoju sterowania ciągiem silnika odrzutowego za pomocą różnych rozwiązań konstrukcyjnych. Scharakteryzowano sterowanie za pomocą dodatkowych klap, dyszy prostokątnej oraz dysz osiowo-symetrycznych obrotowych i segmentowych. Przedstawiono wyniki realizacji programów badawczych z zastosowaniem różnych rozwiązań konstrukcyjnych sterowania ciągiem samolotów wojskowych o dużej manewrowości.

11

Comparative performance analysis and modeling of tool wear in drilling

Wen C. C., Soon L. T., Sivarao

International Journal of Applied Mechanics and Engineering

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2004

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Vol. 9, no spec.

33-38

EN

To date, process supervision or monitoring is mainly performed by limit value checking of some measurable variables. In high automated machine tool faults like tool breakage often cause long outage times and high cost. Drill holes are one of the most common manufacturing features specified on process plans. Because holes are drilled in finished products, the rejection parts due to poor hole quality can be very expensive. It was estimated that 60% of all parts rejections due to poor hole quality. On the other hand, a work piece must often be re-machined or completely rejected when the tool has failed. The investigation of this paper deals with comparative quality and performance of twist drills of different make possessing same geometry. The paired comparison is to be carried out by considering thrust force and torque as the main criteria to determine the better tool among tool X and tool Y. Analytical methods namely, statistical analysis and inverse coefficient matrix analysis were used to validate the experimental result.

12

Comparative analysis and modeling of surface roughness in drilling

Wen C. C., Soon L. T., Sivarao

International Journal of Applied Mechanics and Engineering

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2004

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Vol. 9, no spec.

305-311

EN

Drilling is one of the basic, most frequently performed materials removing process in manufacturing industry. In spite of significant increase in the demand for economically producing holes, drill manufacturing is still considered as an esoteric art. The drilling operation is frequently used as a preliminary step for many operations like boring, reaming and tapping. Surface roughness plays an important role in product quality and manufacturing process planning. Twist drills are used in a diameter range from 1 to 20mm. Surface finish quality of work piece is an issue of main concern to the manufacturing industry and the inspection of surface roughness of the work piece is a very important technology. Drill wear has a bad effect on the surface finish and dimensional accuracy of the work piece. There still exists a lack of knowledge on the exact relationship between the point geometry, the grinding process parameters and the process machines, resulting in many methods for drill production and consequently wide variation in process performance. The variables selected for modeling of surface roughness are cutting speed, cutting feed, machining time and thrust force. The relative comparison of drilled surface produced by twist drills by different make (tool X and tool Y) is to be carried out by actual measurement, statistical analysis and inverse coefficient matrix method.

13

Wpływ geometrii przekroju poprzecznego warstwy skrawanej w strefie przy osi wiertła na jego obciążenie

Nowakowski Z.

Archiwum Technologii Maszyn i Automatyzacji

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2004

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Vol. 24, nr 2

69-76

PL

W artykule przedstawiono wyniki pomiarów sił dla różnych konstrukcji wierteł z płytkami wymiennymi. Pomiary wykonano podczas obróbki stali WCL w stanie miękkim (295 HV02) i zahartowanym (58 HRC). Przeanalizowano wpływ przekroju poprzecznego warstwy skrawanej w strefie przy osi wiertła na wartość siły promieniowej F,7, oraz wypadkowej siły odporowej Fp. Oceniono zmiany stosunku obciążenia ostrza wewnętrznego do zewnętrznego dla wiertła z płytkami wymiennymi w zależności od stanu materiału obrabianego (miękki, zahartowany).

EN

In the article results of forces measurements for various constructions of indexable insert drills have been shown. Measurements have been carried out during machining of the WCL steel in soft (295 HVo,2) and hardened (58 HRC) state. Influence of cut form in zone near axis of the drills on value of radial force F,.p and resultant thrust force F,, has been analyzed. Comparison of changes of load on internal wedge to load on external wedge ratio for given construction of indexable insert drill depending on state of work material (soft, hardened) has been done as well.

14

Badania nad modelami predykcyjnymi dla wiercenia

Mieszczak W., Latocha R.

Prace Naukowe Katedry Budowy Maszyn / Politechnika Śląska

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2001

|

nr 2

187-196

PL

W artykule przedstawiono badania mające na celu uzyskanie zależności matematycznych pomiędzy siłą posuwową i obwodową siłą skrawania a wybranymi cechami geometrycznymi klasycznego wiertła krętego oraz granicą wytrzymałości materiału obrabianego.

EN

The paper presents results of investigation on predictive models for drilling. The main goal of the investigation was to find mathematical dependences between thrust and circumferential cutting force and some geometrical futures of the twist drill and tensile breaking stress.