Search

In the milling process, the material removal rate is limited by the rated power of spindle motor, the stiffness which affect chatter and deformation of the machine and tool, and the geometry of the tool. This limit depends on the combination of the workpiece, machine, tool holder, and tool. In this paper, a new model to predict the limit of the material removal rate for each combination is made by machine learning techniques and the accumulated data of cutting tests. The model shows how to choose the optimal tool and cutting conditions to maximize the material removal rate.

Some studies have shown that prophylactic lateral neck dissection (pLND) may be beneficial for patients with papillary thyroid carcinoma (PTC); however, none of the Western guidelines currently recommends this procedure. Since 2007, the decision to perform pLND at our institution has been made on a case-by-case basis with different risk factors in mind. In this study, we investigated the significance and indications of pLND in patients with PTC.

We recently reported that lowering serum thyroid stimulating hormone (TSH) levels with levothyroxine (LT4) may be associated with decreased tumor growth during active surveillance (AS) of papillary thyroid microcarcinoma (PTMC). Most clinicians might believe that low serum TSH levels following LT4 therapy indicate subclinical thyrotoxicosis. This study aimed to evaluate the effects of TSH-lowering therapy using small doses of LT4 on serum thyroid hormone levels in euthyroid patients with PTMC. We retrospectively analyzed data from 28 patients with low-risk PTMC who had undergone measurement of both FT4 and FT3 consecutively and received LT4 to achieve serum TSH levels of <0.5 μIU/mL and >0.05 μIU/mL between January 2012 and May 2018 at Kuma Hospital. There were 24 females and 4 males (aged 55±12 years [mean ± standard deviation {SD}]). We compared their serum FT4 and FT3 levels at diagnosis with those following TSH-lowering therapy with LT4. Following LT4 therapy, the patients’ serum FT4 levels were significantly increased (P< 0.001). Serum FT3 levels, however, remained unchanged (P= 0.10). The proportions of patients whose FT3 levels increased by more than 1SD, remained unchanged, and decreased by more than 1SD were 11%, 57%, and 32%, respectively. Our study indicated that mild TSH-lowering doses of LT4 for euthyroid patients with PTMC increased serum FT4 levels but did not increase serum FT3 levels in most cases, suggesting that a mild TSH-lowering therapy for euthyroid patients may not necessarily cause thyrotoxicosis.

Quality management of machine tools is the key to reducing downtime of customers’ machines and the manufacturers’ service cost. This paper introduces DMG MORI's systematic workflow from designing, procurement, manufacturing, and acceptance inspections to the delivery of machines, which contributes to improvement of machine quality. Two quality management systems, one for before shipment and the other for after shipment, are described in this paper. Various workflow systems, data analysis, remote monitoring, continuous Kaizen approaches are integrated in the systems. However, defects of machines cannot be completely eliminated, so proactive maintenance and strong service networks are vital for business success. Especially, proactive maintenance is favorably accepted in the industry as a solution to minimize machine downtime and the repairing cost. This paper introduces various sensing technologies to improve the functions of proactive maintenance.

Machine tools are usually used over a long period of more than 10 years, so providing appropriate services are significantly important. Machine tool manufacturers, who develop their businesses worldwide, locate their service bases and parts centers across the world to improve their service quality and provide prompt services to customers. Moreover, if necessary maintenance work is identified before machine tools break down, machine tool manufacturers can make plans to provide systematic services, and users can prevent machine stoppage. This paper describes the development of the sensing interface and the technology to analyze the operating status of machines to implement preventive maintenance.

Additive manufacturing (AM) is increasingly being pursued as a practical approach for component manufacturing. Current AM technologies present certain challenges that are solvable with novel additive/subtractive hybrid machine platforms. Production of work pieces with consistent and viable material properties remains elusive. This work reports on a primary study to define combinations of additive process parameters and nozzle selection that result in quality work pieces. Specifically, AM work pieces of X2CrNiMo17-12-2 and Inconel 625 where characterized principally by porosity followed by tensile strength, hardness, and microstructure to determine optimal process parameters. A Taguchi analysis suggested desired work piece quality is achievable on a hybrid machine platform by adjusting AM process parameters

The modern manufacturing shop floor contains a variety of different types of machining equipment, each supporting different proprietary interfaces and communication protocols. This diversity has made it extremely challenging for shop managers to monitor and maintain their machines. Fortunately, the emerging MTConnect standard makes it possible for a monitoring system to accurately and consistently collect data from any MTConnect compatible machine, regardless of its brand or origin. This paper introduces a web-based machine monitoring system that provides data collection, analysis, and machine event notification for MTConnect compatible machines. This solution provides shop managers with the information needed to improve process efficiency on the shop floor, and increase overall equipment effectiveness (OEE).

The application of advanced materials is continuously increasing in many fields of industry, primarily in the medical and aerospace. The utilization of traditional machining methods is commonly considered very challenging for advanced materials, such as ceramics, metallic super alloys, and fiber-reinforced materials. The machining of these advanced materials, by means of ultrasonic assistance has been already introduced in the past. In this paper, the flexible integration of state-of-the-art ultrasonic systems in machining centers is presented. Results of the latest machining test examples of advanced materials using ultrasonic-assisted machining are discussed.

Quick and correct service is most important for machine tool users. In order to maintain efficiency of machine tools at customers’ sites, remote maintenance and monitoring system, worldwide spare parts supply system, integration of service parts, education system for service engineers, long-term environmental load reduction are necessary. This paper presents current and future activities of machine tool manufacturers for improving the service system.

Machine tools, which are used in factories for long hours and many years, have a great influence on power consumption of the factories. Therefore, reducing machine tool power consumption is one of the important subjects for today’s machine tool manufacturers. In this paper, we will report on our ongoing efforts to improve energy efficiency of machine tools.

The superiority of machining process integration of integrated machines has drawn more and more attention these days. This paper aims at machining examples of complex-shaped workpieces on the integrated mill turn center. First, it reports complex-shaped applications on the 5-axis mill turn machine tool, and measurement and corrective machining using a non-contact sensor. Then, it introduces the examples of ultrasonic machining of semiconductor, optical materials, and dental materials. Lastly, surface texturing by laser machining.

Reduction of energy consumption has played a significant role in industry. This paper describes a study on reducing energy consumption by machining process improvements. Methods of reducing energy consumption in a manufacturing line consisting of multiple machines are verified. First, to consolidate the processes, a series of horizontal machining centers are replaced with a 5- axis machining center. The energy consumption can be reduced by approximately 8%. The cycle time also becomes shorter by approximately 20%. Since transfer equipment is not needed in the process, reduction of energy consumption by eliminating the equipment can also be expected. Second, energy consumption in the machine tool is classified in detail. As a result, it is found that coolant related equipment consumed approximately 54% of the overall energy. Thus, the efforts are focused on the equipment. Coolant consumption of each pump is investigated. Based on the result, the coolant pumps can be concentrated in a single unit. In addition, energy consumption of the through-spindle coolant system is reduced and coolant pressure is optimized. Herewith energy consumption can be reduced by approximately 26%. Finally, the inverter frequency is optimized. As a result, the overall energy consumption in the manufacturing line is reduced by approximately 42%.

An open servo control system for an intelligent CNC machine tool system has been proposed and developed. The developed system is equipped with real-time access window, through which user custom application software can monitor or modify any parameters and variables of servo system in a real time manner as a parallel session while the standard servo control is being performed. The developed system has been implemented in a CNC vertical machining center for feasibility study by integrating the software model reference adaptive control as custom application. The experimental results have successfully demonstrated the effectiveness of the open servo system.