Einfluss von Strukturkomponenten aus Zementbeton*/Influence of components made of cement concrete

2018 ◽  
Vol 108 (03) ◽  
pp. 191-196
Author(s):  
C. Prof. Brecher ◽  
C. Kiesewetter ◽  
S. Schmidt ◽  
A. Epple
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Dynamic Behavior ◽  
Machine Tools ◽  
Experimental Investigations ◽  
Structural Components ◽  
Cement Concrete ◽  
Alternative Materials

Werkzeugmaschinen werden vorwiegend aus Stahl oder Gusseisen hergestellt. Zur Kostenreduktion und Verbesserung des dynamischen Verhaltens der Maschinen existieren jedoch auch Bestrebungen, alternative Werkstoffe – zum Beispiel Zementbeton – im Werkzeugmaschinenbau einzusetzen. Dieser Fachartikel stellt die Ergebnisse messtechnischer Untersuchungen an einer am WZL konstruierten Miniaturmaschine mit zwei Strukturkomponenten aus Zementbeton vor.   Machine tools are predominantly produced out of steel or cast iron. In order to reduce costs and improve the dynamic behavior of the machines, there are also efforts to utilize alternative materials such as cement concrete in machine tool constructions. Therefore, this article presents the results of experimental investigations of a miniature machine designed at the WZL with two structural components made of cement concrete.

Material Considerations in Optimization of Machine Tool Structure

2001 ◽  
Author(s):  
Emmanuil F. Kushnir ◽  
Mahendra R. Patel ◽  
Terrence M. Sheehan
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Polymer Composites ◽  
Polymer Composite ◽  
Machine Tools ◽  
High Speed ◽  
Impact Resistance ◽  
Vibration Damping ◽  
Structural Components ◽  
Cumulative Impact

Abstract The three most popular choices currently used for the main structural components of machine tools are steel weldments, metal (cast iron) castings and polymer composites. Among the three, polymer composite offers the highest vibration damping and the lowest thermal conductivity. All three approaches have been employed in the design of machine tools to meet the criteria for required rigidity, impact resistance and vibration damping. The final choice is also affected by additional factors including cost footprint (space) requirements and lead times. For most production applications of machine tool structures, (gray cast iron) metal castings remain the primary choice because of cost, ease of sourcing, good damping with relatively high strength, good machinability and well-established and consistently achievable manufacturing and processing requirements. However, fabrications are normally the preferred choice for low volume production of large structures, due mainly to the high up-front molding costs and the difficulties in process control inherent in very large castings. On the other hand, with increasing, emphasis on high speed machining, hard turning, and better and consistent machining accuracies, structural rigidity, thermal stability and vibration damping are becoming major design considerations making polymer composites a leading choice. For this reason, Hardinge Inc., a super precision machine tool builder has traditionally used its proprietary polymer composite (Harcrete®) in its lathe, grinder and machining center bases. Depending on the performance and cost requirements, the base can be all composite or a combination of conventional casting strategically reinforced with composite. With the current market forces and ever increasing competition in the industry, for most machines, value engineering has become a prominent factor. A major consideration is to identify the materials and designs that would provide the best performance of the machine while minimizing the cost. Therefore, new sets of evaluation criteria are necessary to arrive at designs with optimum cumulative impact on various technical, commercial and strategic requirements. This paper proposes such new criteria and examines their suitability based on testing and analyses of structural components in today’s demanding real-world machine tool applications.

scholarly journals Cast Iron And Mineral Cast Applied For Machine Tool Bed - Dynamic Behavior Analysis

2015 ◽  
Vol 60 (2) ◽  
pp. 1023-1029 ◽  
Author(s):  
N. Kępczak ◽  
W. Pawłowski ◽  
Ł. Kaczmarek
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Machine Tools ◽  
Dynamic Properties ◽  
Dynamic Stiffness ◽  
Physical And Mechanical Properties ◽  
Strength Properties ◽  
Structural Elements ◽  
Static Structure ◽  
Static Rigidity

Abstract Cast iron and mineral cast are the materials most often used in the machine structural elements design (bodies, housings, machine tools beds etc.). The materials significantly differ in physical and mechanical properties. The ability to suppress vibration is one of the most important factors determining the dynamic properties of the machine and has a significant impact on the machining capabilities of a machine tool. Recent research and development trends show that there is a clear tendency to move away from the traditional iron casting to the mineral casting, due to better dynamic properties of the latter. However mineral cast as a structural material for the whole machine tools bed turns out to be insufficient due to its poor mechanical strength properties. The best solution should benefit from the advantages of the cast iron and mineral cast materials while minimizing their drawbacks. The paper presents numerical modal analysis of two lathe beds: the first one made of gray cast iron and the second one made of hybrid connection of cast iron and mineral cast. The analysis was conducted in order to determine the dynamic properties of two bodies of similar shapes made in the traditional (cast iron) and innovative hybrid (cast iron and mineral cast) technology. In addition, an analysis of the static structure rigidity of the two beds was performed. During the simulation studies it was found a significant increase in dynamic stiffness and static rigidity of the machine tool body made of hybrid connection of cast iron and mineral cast. The results of numerical simulations have confirmed the desirability of using hybrid construction because the dynamic properties of such a body are more advantageous in comparison with the conventional body made of cast iron.

scholarly journals Stiffness and Damping of Epoxy Granite

2020 ◽  
Vol 9 (3) ◽  
pp. 1105-1108
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Machine Tools ◽  
Weight Ratio ◽  
High Strength ◽  
Cutting Conditions ◽  
Polymer Concrete ◽  
Machine Tool Structures ◽  
Conventional Machine ◽  
Stiffness And Damping

The productivity and accuracy of machine tools now became most significant as the cutting conditions changes continuously. Therefore to withstand against these cutting conditions the machine tool structural material must have higher stiffness and damping. This review deals with various research works to study the stiffness and damping of epoxy granite or polymer concrete. It is reported that the epoxy granite shows improved damping and high strength to weight ratio than that of conventional machine tool structures of steel and cast iron.

Efficient Dynamic Parameter Identification Framework for Machine Tools

2020 ◽  
Vol 142 (8) ◽  
Author(s):  
Thomas Semm ◽  
Markus Sellemond ◽  
Christian Rebelein ◽  
Michael F. Zaeh
Keyword(s):  
Machine Tool ◽  
Parameter Identification ◽  
Dynamic Behavior ◽  
Machine Tools ◽  
Dynamic Models ◽  
Dynamic Parameter ◽  
Multibody Model ◽  
Physical Prototype ◽  
The Individual ◽  
Dynamic Parameter Identification

Abstract Modeling the dynamic behavior of a machine tool accurately is a difficult but crucial task when optimizing a machine tool’s design. An accurate representation of the real behavior is essential to ensure the transferability of simulations from a virtual prototype to a physical prototype. Due to the complexity of modern machine tools, a large number of parameters have an influence on the dynamic behavior. The parameterization of the used dynamic models is still challenging, especially if intricate local models are used for the individual effects. This paper presents an efficient framework for parameterizing a dynamic model of a machine tool containing linear local damping and stiffness parameters. For parameter identification, measurements of single components on simple test rigs as well as measurements of the whole machine tool were carried out. Different numerical optimization algorithms as well as objective functions were compared and applied to a three-axis machine tool structure for parameter fitting. By using a parametric reduced-order flexible multibody model for the fitting, high accuracy can be combined with high computational efficiency. The use of the presented approach allows an efficient parameter estimation and lays the groundwork for an influence analysis and the targeted optimization of a machine tool.

scholarly journals The welded CNC machine tool frame

2018 ◽  
Vol 157 ◽  
pp. 01003 ◽  
Author(s):  
Piotr Boral ◽  
Tadeusz Nieszporek ◽  
Rafał Gołębski
Keyword(s):  
Cast Iron ◽  
Machine Tool ◽  
Machine Tools ◽  
Cnc Machine Tools ◽  
Polymer Concrete ◽  
Cnc Machine ◽  
Welded Steel ◽  
University Of Technology ◽  
Conventional Machine ◽  
Solid Works

Machine tools are built based on cast-iron bodies. Cast iron well dumps down vibrations and is dimensionally stable. Therefore, many conventional machine tools are modernized and modified into CNC machine tools based on the seasoned old bodies of those machine tools. Nevertheless, CNC machine tools are also manufactured based on polymer concrete, which vibration damping ability is even better. On the other hand, attempts made in the past by leading machine tool manufacturers to use welded frames in CNC machine tools failed. The revival of interest in welded frames was spurred by economic considerations, as steel systems are much thinner compared to cast-iron ones. They are able to carry the same loads. The construction of CNC machine tools with a welded steel frame undertaken at the Institute of Mechanical Technologies (ITM) of the Czestochowa University of Technology is an attempt to solve this constructional problem. The machine tool frame was designed with use of CAD solid works system. The ultimate success of using the welded frame is determined not only by the frame itself, but also generally the design of the machine tool and its operation parameters. The welded frame was used for a high-accuracy three-axis milling machine. In this respect, it is equal of professional machine tools manufactured by reputed companies. It can be either a production machine tool or a test stand.

MEEHANITE GA

Alloy Digest ◽  
1954 ◽  
Vol 3 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Shear Strength ◽  
Cast Iron ◽  
Physical Properties ◽  
Machine Tools ◽  
High Strength ◽  
Heat Treating ◽  
Damping Capacity ◽  
Iron And Steel ◽  
Lubricating Properties

Abstract MEEHANITE GA is a high strength iron casting having high damping capacity, self-lubricating properties, and good machinability. It combines the good properties of both cast iron and steel. Applications include machine tools, gears, shafts, and housings. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive and shear strength as well as fracture toughness and fatigue. It also includes information on heat treating and machining. Filing Code: CI-5. Producer or source: Meehanite Metal Corporation.

scholarly journals Recurrent neural networks with long term temporal dependencies in machine tool wear diagnosis and prognosis

2021 ◽  
Vol 3 (4) ◽  
Author(s):  
Jianlei Zhang ◽  
Yukun Zeng ◽  
Binil Starly
Keyword(s):  
Neural Network ◽  
Tool Wear ◽  
Machine Tool ◽  
Recurrent Neural Network ◽  
Machine Tools ◽  
Prediction Performance ◽  
Sequential Data ◽  
Diagnosis And Prognosis ◽  
Proposed Model

AbstractData-driven approaches for machine tool wear diagnosis and prognosis are gaining attention in the past few years. The goal of our study is to advance the adaptability, flexibility, prediction performance, and prediction horizon for online monitoring and prediction. This paper proposes the use of a recent deep learning method, based on Gated Recurrent Neural Network architecture, including Long Short Term Memory (LSTM), which try to captures long-term dependencies than regular Recurrent Neural Network method for modeling sequential data, and also the mechanism to realize the online diagnosis and prognosis and remaining useful life (RUL) prediction with indirect measurement collected during the manufacturing process. Existing models are usually tool-specific and can hardly be generalized to other scenarios such as for different tools or operating environments. Different from current methods, the proposed model requires no prior knowledge about the system and thus can be generalized to different scenarios and machine tools. With inherent memory units, the proposed model can also capture long-term dependencies while learning from sequential data such as those collected by condition monitoring sensors, which means it can be accommodated to machine tools with varying life and increase the prediction performance. To prove the validity of the proposed approach, we conducted multiple experiments on a milling machine cutting tool and applied the model for online diagnosis and RUL prediction. Without loss of generality, we incorporate a system transition function and system observation function into the neural net and trained it with signal data from a minimally intrusive vibration sensor. The experiment results showed that our LSTM-based model achieved the best overall accuracy among other methods, with a minimal Mean Square Error (MSE) for tool wear prediction and RUL prediction respectively.

Application of Ubiquitous Sensor Network in Collection and Analysis of CNC Machine Tool Processing Status Information

2010 ◽  
Vol 455 ◽  
pp. 621-624
Author(s):  
X. Li ◽  
Y.Y. Yu
Keyword(s):  
Machine Tool ◽  
Sensor Network ◽  
Machine Tools ◽  
Thermal Error ◽  
Development Trend ◽  
Cnc Machine Tools ◽  
Cnc Machine Tool ◽  
Cnc Machine ◽  
Status Information ◽  
The Development Trend

Because of the practical requirement of real-time collection and analysis of CNC machine tool processing status information, we discuss the necessity and feasibility of applying ubiquitous sensor network(USN) in CNC machine tools by analyzing the characteristics of ubiquitous sensor network and the development trend of CNC machine tools, and application of machine tool thermal error compensation based on USN is presented.

Efficiency Improvement of Metal Lathing by Using of an Evaluation Technique of Assembly Machine Tools Quality

2016 ◽  
Vol 684 ◽  
pp. 421-428 ◽  
Author(s):  
D.S. Vasilega ◽  
M.S. Ostapenko
Keyword(s):  
Machine Tool ◽  
Machine Tools ◽  
Quality Evaluation ◽  
Composite Index ◽  
Production Operation ◽  
Evaluation Technique ◽  
Efficiency Improvement ◽  
Index Of Quality

They defined conditions of use, calculated a composite index of quality for different tools, chose a machine tool according to its quality evaluation, calculated efficiency of processing by tools with different parameters for a certain production operation.

Sign in / Sign up

Export Citation Format

Share Document