|
|
On the analysis of spring steel machinability after a heat treatment
Vašíček, František ; Humár, Anton (referee) ; Píška, Miroslav (advisor)
This thesis deals with the machinability spring steel after heat treatment. Brief research is devoted to the machinability of steel with a focus on spring steel, various influences acting on the material and selected types of heat treatment. On the example of deteriorated workability of Disc spring are described methods of material analysis, performace and influences on machinability. By assessment of the results of the analysis were identified possible causes of deterioration of machinability from view of heat treatment – soft annealing. The final part discusses possible corrective actions in the annealing process and proposes a non-destructive method for controlling material structures.
|
|
| |
|
|
Wear of cutting tools at CNC production of the disc-shaped parts
Malý, Michal ; Polzer, Aleš (referee) ; Píška, Miroslav (advisor)
This diploma thesis evaluates two competitive cutting inserts for machining of disk-shaped blanks. The first part summarizes theoretical knowledge of turning, wear of cutting inserts and cost analysis of the cutting process. In the second part, the wear of two inserts from a different manufacturer is observed in two different cutting speeds. Wear is evaluated by electron microscope images. In the end, there is an economic evaluation of both VBD in different cutting speeds for serial production.
|
|
|
Optimizing of die geometry for wet drawing of a steel wire with process fluid
Bršťák, Ondřej ; Zmrzlý, Martin (referee) ; Píška, Miroslav (advisor)
The subject of this diploma thesis was both the analysis of the wire drawing process and the design of a new drawing die. All tests were performed at real production line. The primary aim of the analysis was the change in the current lubricating medium. Based on the performed analysis the test was developed to determine the exact values of the friction coefficient of the new lubricant. In the following part of the thesis the wire manufacturing process was described with a focus on the performance of the drawing die. For that matter material tests were performed and a material model was developed and then used for further calculations. Based on the results the geometry of the drawing die was changed and hence the drawing process was optimized with the focus on both increasing the lifetime of the drawing die and maintaining the complexity of the production. First drafts of new drawing dies were created and cost savings were calculated. In the last section the next modifications were proposed to increase the lifetime of the drawing dies.
|
|
|
Wear of cutting tools at CNC production of the disc-shaped parts
Malý, Michal ; Polzer, Aleš (referee) ; Píška, Miroslav (advisor)
This diploma thesis evaluates two competitive cutting inserts for machining of disk-shaped blanks. The first part summarizes theoretical knowledge of turning, wear of cutting inserts and cost analysis of the cutting process. In the second part, the wear of two inserts from a different manufacturer is observed in two different cutting speeds. Wear is evaluated by electron microscope images. In the end, there is an economic evaluation of both VBD in different cutting speeds for serial production.
|
|
|
Contact between end coils of cylindrical helical compression springs
Nekoksa, Pavel ; Grulich, Tomáš (referee) ; Kašpárek, Jaroslav (advisor)
This diploma thesis deals with hot-formed helical compression springs. The first part of the thesis describes related problems and determines market potential. Following theoretical part describes the influence of contact line on behaviour of springs and compares it with normative regulations. Methods suitable for determination of helix shape are covered in the next part. The last part focuses on practical measurement, in which the change of helix shape during manufacture was observed. The main output of this diplomat thesis is suggestion of measures that should contribute to both optimization of manufacture and verification of FEM model.
|
|
|
An innovation of the CNC production of the disc-shaped parts
Křupka, Marek ; Humár, Anton (referee) ; Píška, Miroslav (advisor)
The optimal choice of cutting conditions, as well cutting tool, has a significant effect on the quality of machined part and is an essential parameter to reduce the cost of production. This thesis describes CNC turning process of disc springs made of 51CrV4 material, especially using new cutting tools and the use of higher cutting speeds. A comparison of four manufacturers of cutting tools in terms of surface quality, tool path and the machined material volume will be introduced. It was experimentally verified that our proposed facility has achieved the best result.
|
|
| |
|
|
On the analysis of spring steel machinability after a heat treatment
Vašíček, František ; Humár, Anton (referee) ; Píška, Miroslav (advisor)
This thesis deals with the machinability spring steel after heat treatment. Brief research is devoted to the machinability of steel with a focus on spring steel, various influences acting on the material and selected types of heat treatment. On the example of deteriorated workability of Disc spring are described methods of material analysis, performace and influences on machinability. By assessment of the results of the analysis were identified possible causes of deterioration of machinability from view of heat treatment – soft annealing. The final part discusses possible corrective actions in the annealing process and proposes a non-destructive method for controlling material structures.
|
guest ::
