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Journal PROCEEDINGS IN MANUFACTURING SYSTEMS |
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ISSN 2343–7472 ISSN-L 2067-9238 |
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Journal PROCEEDINGS IN MANUFACTURING SYSTEMS
□ Volume 12, Issue 2, 2017
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Radu-Eugen BREAZ, Sever-Gabriel RACZ, Melania TERA, Mihai CRENGANIȘ,
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Evangelos NIKOLIDAKIS, George-Christopher VOSNIAKOS,
A novel tool clamping system for CNC press brakes
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Thomas STÖHR, Christian LANDSCHÜTZER,
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Dan
PRODAN, George CONSTANTIN, Anca BUCUREȘTEANU,
Retrofitting of the hydraulic installation of a CNC
lathe for re-profiling railway wheelset
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Gabriel FRUMUŞANU, Virgil TEODOR, Nicolae OANCEA,
Solution aiming the technological improvement of worm
and star wheel from single screw compressor
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Melania TERA, Radu-Eugen BREAZ,
Adaptive
network based inference system for cutting force simulation in milling of
multi-layered metal materials
Uros
ZUPERL1,*, Franc CUS2
1) Assist. Prof., Researcher, University of Maribor, Faculty of Mechanical
Engineering, Maribor, Slovenia
2) Full. Prof., University of Maribor, Faculty of Mechanical Engineering,
Maribor, Slovenia
Abstract:
This paper outlines the
experimental research on cutting forces produced during ball-end milling of
multi-layered metal materials manufactured by the laser engineered net
shaping (LENS) process. The research employs an adaptive neuro-fuzzy
inference (ANFIS) modelling technique for simulating the dynamic cutting
force components during the machining of 16MnCr5/316L four-layered metal
material with a solid carbide ball-end mill. A Kistler dynamometer was used
to measure the actual cutting force, which was compared with the estimated
one obtained via suggested procedure. Hardness and thickness of the
particular manufactured layer in above mentioned advanced material have been
considered during developing of the ANFIS models. Analysis of the developed
models has been performed to test their validity. Model predictions were
compared with experimental data and were found to be in good agreement.
Experimental results demonstrate that this method can accurately predict
cutting force within a maximum prediction error of 4.1%.
The
implementation of a modular open architecture PC-based CNC system used as a
research and education equipment
Radu-Eugen BREAZ1,*,
Sever-Gabriel RACZ2, Melania TERA3, Mihai CRENGANIȘ3 1)
Prof., PhD, Department of Industrial Machines and Equipment, "Lucian Blaga"
University of Sibiu, Sibiu, Romania 2)
Prof., PhD, Head of Department, Department of Industrial Machines and
Equipment, "Lucian Blaga" University of Sibiu, Sibiu, Romania 3)
Ass. Prof., PhD, Department of Industrial Machines and Equipment, "Lucian
Blaga" University of Sibiu, Sibiu, Romania 3)
Ass. Prof., PhD, Department of Industrial Machines and Equipment, "Lucian
Blaga" University of Sibiu, Sibiu, Romania
Abstract:
Open-architecture CNC
technological equipment are used nowadays both for industrial and
educational purposes. Using a modular structure and a PC-based CNC
controller, these devices allow the users to develop and test new control
and machining strategies, to train in the field of CNC programming and
CAD/CAM techniques, while keeping the costs as low as possible, in
comparison with the industrial, closed architecture, CNC machine-tools.
However, the modular, reconfigurable, structure and consequently the modular
assembly method, comes with some drawbacks, most of them related the
accuracy of the system. Also, PC-based open architecture controllers lacks
some important features linked with 4&5-axis indexed machining and 4&5-axis
continuous machining, which normally are present in industrial CNC
controllers. Among these features, the ability to use local coordinate
systems and the ability of using tool center point management are the most
important, and their absence makes the use of CNC machines with PC-based
open architecture for multi-axis machining quite difficult. This paper
present the implementation of a 5-axis modular CNC machining center, built
in a modular way and using LinuxCNC as PC-based CNC controller. Some methods
for improving the accuracy of the equipment and strategies to overcome the
difficulties related to 4&5 axis machining are presented.
A
novel tool clamping system for CNC press brakes
Evangelos NIKOLIDAKIS1,
George-Christopher VOSNIAKOS2,* 1)
Dipl. Mech. Eng., School of Mechanical Engineering, National Technical
University of Athens, Athens, Greece 2)
Prof., PhD, School of Mechanical Engineering, National Technical University
of Athens, Athens, Greece
Abstract:
Tools of
CNC press brakes
are
attached to the ram of the press by conventional
clamping systems ensuring firm support but not easy exchange, because they
rely on tightening and loosening of a large number of screws. Some
non-conventional proprietary systems are available in the market exploiting
pneumatic, hydraulic or mechanical clamping principles and were reviewed to
reveal that they provide much quicker tool replacement than conventional
systems but they still exhibit some discrepancies. Thus, improved clamping
system specifications were designated and a new hydraulic operated clamping
system was developed consisting of 18 different types of parts and a
hydraulic unit.
Detailed
design of the system is presented including step-by-step explanation of its
function. Analysis of the system pertains to clamping force calculation, to
strength calculation of the main parts using finite element analysis, to
process plan and cnc program development for the three main components, to
design/calculation of the accompanying hydraulic unit and to basic costing.
A ‘proof-of-concept’ prototype was 3D printed.
Thus, it was proved that the
clamping system satisfies the specifications set and that its production,
even in small batches, entails
reasonable cost. This is a promising replacement to conventional clamping
systems when minimisation of press brake setup time is desirable.
Simulation models for material handling equipment design – evaluation
criteria, methods and application
Thomas
STÖHR1, *, Christian LANDSCHÜTZER2
1) Dipl.-Ing, University Project Assistant, Institute of Logistics
Engineering, Graz University of Technology, Austria
2) Assoc.Prof. Dipl.-Ing. Dr.techn., Co-Chairman, Institute of Logistics
Engineering, Graz University of Technology, Austria
Abstract:
Decisive
criteria for the efficient use of CAE are available and well proven but are
focusing on engineering in general. These decisive criteria are hardly being
transferred to Intralogistics. A CAE application method out of a pool of
engineering tools of the Institute of Logistics Engineering TU Graz (ITL)
tries to close this gap. In the application field logistics engineering the
method assigns simulation tools by usage criteria to engineering phase
methods and their design principles. This method can contribute to spread
CAE and to lower application effort. The authors depict this method, give an
exemplarily use and illustrate the benefit by two different simulation
models (use cases) in two different application fields of logistics
engineering.
Retrofitting of the hydraulic installation of a CNC lathe for re-profiling
railway wheelset
Dan
PRODAN1,*, George CONSTANTIN2, Anca BUCUREȘTEANU3
1, 2, 3) Prof., PhD, Eng., Machines and Manufacturing Systems
Department, University “Politehnica” of Bucharest, Romania
Abstract:
On the occasion of refabrication
of a specialized parallel lathe, designed for the processing of railway
wheels (whellset), the authors of this article designed and built a new
hydraulic installation. This new installation correlates with the new
working method of the machine tool. Initially, the lathe, fitted with two
main shafts that work "in the mirror", realized the specific profile of
these wheels by copying. After refabrication, the machine tool works in with
CNC. After the realization of the hydraulic project, the simulation of the
dynamical operation of the lifting/lowering system of the blank/workpie was
performed. The lifting/lowering system works with inertial masses up to 2000
kg, requiring positioning precision and repeatability. Due to the large
weight of the semifinished, but also due to the precision requirements
specific to the CNC machine tools, it is imperative that the clamping and
locking systems to be very firm and secure.
Solution
aiming the technological improvement of worm and star wheel from single
screw compressor Gabriel
FRUMUŞANU1,*, Virgil TEODOR2,
Nicolae OANCEA3 1),
3) Prof., PhD, Manufacturing Engineering Department, “Dunărea de
Jos” University of Galaţi, Romania 2)
Assoc. Prof., PhD, Manufacturing Engineering Department, “Dunărea de Jos”
University of Galaţi, Romania
Abstract:
Single screw compressors are
frequently used due to their constructive simplicity, leading to a lower
price. The level of functional noise is also lower than in the case of other
compressors. They usually include a central worm whose profile is generated
by a star wheel with rectangular transversal profile. This paper proposes a
solution enabling an easier machining of the worm, with the help of an end
mill cutter. A new shape of the star wheel tooth is proposed, issuing from
the analysis of central worm – star wheel gear, on the base of the
fundamental theorems of reciprocal enwrapped surfaces. As consequence, a new
constructive solution for the star wheel, which is the element that ensures
compressor’s sealing, is suggested. An analytical solution of the specific
enwrapping surfaces problem is presented together with the new constructive
shape of the star wheel.
Considerations regarding the incremental forming process in manufacturig
Melania
TERA1,*, Radu-Eugen BREAZ2
1) Assist. Prof. PhD., Industrial Machines and Equipments Department,
Faculty of Engineering, "Lucian Blaga" University of Sibiu, Sibiu, Romania
2) Prof., Ph.D., Industrial Machines and Equipments Department, Faculty of
Engineering, "Lucian Blaga" University of Sibiu, Sibiu, Romania
Abstract:
The
incremental deformation process of the sheet metal blanks allows the
realization, without the use of dies with a high degree of complexity, of a
wide variety of parts, mostly for automotive (car body parts) and
bio-medical industry (prosthetic devices). The process has great flexibility
and could represent a manufacturing solution when small batches or even
prototypes of complex sheet metal parts must be manufactured. However, many
technological aspects of the process are still to be researched and
improved, to determine manufacturing companies to implement it on
wide-scale, industrial basis. The paper gave an overview, based upon both a
literature review and some results obtained by the authors of the present
work, over the main aspects of incremental forming process as manufacturing
solution for sheet metal parts. The main methods, tools and technological
equipment used within the process are presented. The study focuses on the
flexible approach regarding single point incremental forming, which involves
the use of 3 axis CNC machine-tools, using hemispherical punches instead of
cylindrical mills, combined with low-price dies for processing the parts. To
further increase the flexibility by using flexible tools that can be easily
adapted to new types of parts, a new modular tool assembly was proposed.
Electronic mail: orgcom@icmas.eu |
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