Adam Janásek

Surface Roughness after Machining and Influence of Feed Rate on Process

The aim of the work is find out influence of feed rate on the quality for the machined surface, especially surface roughness. The experiment was carried out by cutting tool HURCO VMXt30 with respect to the following cutting parameter: cutting speed 250; 350; 450; 550 and 850 m.min-1, feed 0,1; 0,5 and 1,0 mm/tooth. For testing was used two most common materials in the steel grade 1.1191 (12 050) and 1.2343 (19 552), and we chose two ordinary parameters of surface roughness; Ra - arithmetical mean roughness deviation and Rz - the largest inequalities height profile in the transverse direction and the longitudinal direction of machining. The structural equations will be the result which can describe the character depending on the cut surface parameters.

Surface Integrity at Reaming by Reamer MT3 Head

Abstract The article is focused on surface integrity at reaming with high-productive reaming MT3 head made by HAM-FINAL Company. The term surface integrity is the surface condition of a workpiece after being modified by a manufacturing process. A machining process produces a surface characterized by the shape, metallurgy and mechanical properties. These surface aspects clearly indicate that a machined surface is very complex. Obviously, a high-energy input increases the likelihood of metallurgical damage and therefore results in a poor surface integrity which has effect on final product. Taking into account different types of created energy transferred to the tested surface and subsurface layer, the basic factors influencing surface integrity are temperatures, residual stresses, metallurgical transformations and also surface plastic deformation. The aim of experimental part is surface integrity tested on holes by reaming MT3 head during manufacturing process and last aim is find out MT3 head tool-life with their evaluation.

Sleeves’ Cutting Tool-Life Tests for Ceramic Inserts

Abstract The article is focused on the experimental determination of tool-life for ceramic tool. Nowadays, machining with indexable ceramic cutting inserts can reduce manufacturing cost, if the cutting tool and the machine tool are designed to compliment each other. With the development of modern ceramic tool materials, they are more and more widely used in the field of metal cutting since their mechanical properties and cutting performances have been greatly improved in last decades. On the basis of previous tests the tool-wear was measured at constant cutting parameter which is more typical for High Volume Manufacturing Processes. The tested material, cast iron 25P, is used at car’s engine. The main aim of this article was to find out the performance for this material by arithmetic tolerance of Ra profile, the greatest height of Rz profile and the external diameter D and its connection.

Tool Life Reliability of Indexable Cutting Inserts

Abstract This paper presents experimental testing of the cutting ability for indexable cutting inserts. The main goal will be to select a suitable test for determine the cutting abilities of cutting inserts. Nowadays all manufacturers want to achieve lower cutting forces so can permit higher speeds and feeds, without increasing the risk of chipping. For evaluating we had to design such testing procedure that it would be possible to compare and evaluate the cutting ability of the selected cutting inserts used for tests. In today’s competitive global market, quality and precision is the most important parameter. Tight tolerances and urgent deadlines are normal. In the machine tool business, companies must keep their cutting edge, or your company will lose its competitive edge.

Hard Machinable Machining of Cobalt Super Alloys

Abstract The article deals with difficult-to-machine cobalt super alloys. The main aim is to test the basic properties of cobalt super alloys and propose suitable cutting materials and machining parameters under the designation 188 when machining. Although the development of technology in chipless machining such as moulding, precision casting and other manufacturing methods continues to advance, machining is still the leading choice for piece production, typical for energy and chemical engineering. Nowadays, super alloys are commonly used in turbine engines in regions that are subject to high temperatures, which require high strength, high temperature resistance, phase stability, as well as corrosion or oxidation resistance.

Checking the Geometric Accuracy of a Machine Tool for Selected Geometric Parameters

This paper deals with the control parameters for selected geometric accuracy measurements for a machine tool. The parameters were needed after a refurbished milling machine was purchased. After setting up the machine, it was necessary to check the geometric accuracy that can be used for precise milling. The whole check was performed in accordance with ISO 10791. Only selected parameters of geometric accuracy were inspected, and they were later compared with the prescribed values. On the basis of a comparison of these values we were able to determine whether the machine tool can be used for accurate machining.