Modern Machinery (MM) Science Journal, December 2013

AN UNCONVENTIONAL SOFTWARE ENVIRONMENT FOR FACTORY LAYOUT DESIGN AND AUTOMATED CONVERTER

"Petr Horejsi, Jiri Polcar"
Keywords: factory layout | manufacturing | visTable | Source Engine | visualization | Virtual Reality

The development of a company layout is a crucial issue during Product Lifecycle Management. When introducing a new product or innovating the current onewhilst respecting the digital factory concept there is a need for stepping through more phases from a technical point of view: construction, technology and digital manufacturing design. This paper deals with the digital manufacturing design stage only - (…)

INFLUENCE OF SHIELDING GAS ON GMA WELDING OF Al ALLOYS

Ladislav Kolarik, Karel Kovanda, Marie Kolarikova, Petr Vondrous, Jaroslav Kopriva
Keywords: mixture | He | Ar | shielding gas | Al Alloy | GMAW | Welding

The research is focused on influence of shielding gas on GMA welding process of precipitation hard enable Al alloys (6xxx and 7xxx). Pure Ar of different gas flow 0-35 l∙min-1, different Ar+He mixtures, up to 70 % He, active Ar+CO2 gases were used. The optimum Ar shielding gas flow was found to be 15 l∙min-1, where under this value porosity and over this value decrease of weld penetration have been obse (…)

A COMPARATIVE ANALYSIS OF LOWER SPEED CHATTER BEHAVIOUR

Pavel Bach, Milos Polacek, Petr Chvojka, Jiri Drobilek, Ondrej Svoboda
Keywords: lower speed | turning | chatter stability drop

It is known that reduced cutting speeds increase the limit of stability. However, this only applies to milling operations. In turning operations the stability limit initially drops with decreased cutting speed and subsequently rises with a further decrease in cutting speed. A minimum of attention is devoted to this phenomenon in the literature although many authors have noted the decline in the limits o (…)

NUMERICAL AND EXPERIMENTAL DETERMINATION OF SPRINGBACK IN U-BENDING PROCESS

"Miroslav Jurcisin, Jan Slota, Milan Dvorak"
Keywords: Autoform | numerical simulation | bending | Bauschinger effect | Springback

The most common problem in area of bending technology is problem of achieving accurate and repeatable bending angle. This problem is caused by elastic springback. Springback can be defined as an elastically-driven change of shape of the deformed part upon removal of external loads. This phenomenon is observed also in other sheet metal forming processes. Several technological parameters influence springb (…)

INFLUENCE OF FLANK WEAR ON DECOMPOSITION OF CUTTING FORCES IN TURNING

Jaroslav Dubec, Miroslav Neslusan, Anna Micietova, Maria Cillikova
Keywords: turning | fland wear | decomposition | cutting force

This paper deals with influence of flankwear on decomposition of cutting force in turning of roll bearing steel. The decomposition is carried out to evaluate the components of cutting force in the tool-chip as well as tool-workpiece interface. The decomposition enables evaluation of the shear and normal forces in the both interfaces. The results of experiments and the following calculations show that wh (…)