| Abstract | U ovom radu obrađena je tema određivanja zasjeka i ispitivanja točnosti osi CNC plazma rezača kod izrezivanja pločevina konstrukcijskog čelika, aluminija i nehrđajućeg čelika debljina 2, 4 i 6 mm. U uvodnom dijelu objašnjena je plazma kao agregatno stanje i tehnologija plazma izrezivanja. Opisani su njeni napretci i razvoj kroz povijest, područja primjene i različite varijante plazma izrezivanja koje su korištene nekoć i koje se primjenjuju i danas. Potom je objašnjen utjecaj različitih parametara koji određuju način provođenja izrezivanja i analizirani su utjecaji različitih primarnih plinova koji se koriste za formiranje plazmenog mlaza i sekundarnih plinova koji štite formirani plazmeni mlaz. U eksperimentalnom dijelu rada je opisano poduzeće u kojemu se nalazi CNC plazma stroj na kojem se provodio eksperiment, zatim su navedeni materijali koji se izrezuju i njihova svojstva, te parametri koji su korišteni za izrezivanje. Nakon opisivanja materijala, dan je detaljan plan pokusa kreiran u programskom paketu Design – Expert po kojem su se provodila izrezivanja ispitnih uzoraka. Po završetku rezanja, svi ispitni uzorci su izmjereni, te su podaci o odstupanjima njihovih dimenzija po x i y osi i odstupanja promjera provrta tablično prikazani i analizirani programskim paketom Design – Expert. Provedena je statistička analiza izmjerenih podataka da bi se na temelju odstupanja dimenzija ispitnih uzoraka utvrdile optimalne vrijednosti zasjeka i jednadžbe koje opisuju dimenzijska odstupanja za svaki materijal i debljinu. Uz iznose zasjeka, analizom je dobiven i uvid u točnost x i y osi stroja. |
| Abstract (english) | This paper processes the topic of determining the kerf value and axis accuracy of a CNC plasma cutter for the cutting of 2, 4 and 6 mm thick plates of construction steel, aluminum and stainless steel. Introductory part explains plasma as a physical state and the technology of plasma cutting. Its development throughout history, fields of application and different variants of plasma cutting which were used in the past, and which are still being used today, were described. Influence of different parameters which determine how the process will be implemented is explained, along with how do the different gases, which are used to form the plasma jet, and secondary gases, which protect the formed plasma jet, influence the process. Experimental part of the paper describes the firm which houses the CNC plasma cutting machine on which the experiment was performed, afterwards, the materials which are being cut are listed along with their properties and parameters used for the cutting process. After the materials were listed, a detailed plan of the experiment by which the cutting will be performed, created in the Design – Expert software, was given. Upon completition of the cutting, all test samples were measured, and the data regarding their dimensional deviations on x and y axis and hole diameter deviations was tabularly shown and analyzed with the Design – Expert software. Statistical analysis of the measured data was made so that the optimal kerf values and the equations which describe dimensional deviations for each material and thickness could be made, based on the dimensional deviation of the test samples. Along with the kerf values, analysis has also given insight in the accuracy of the x and y axis of the machine. |
