Theory and experimental research on spiral bevel gear by double-side milling method

In this paper, a double-side milling method on spiral bevel gear is proposed. First, according to the tooth taper processed by double-side milling method, the influence of dedendum angle on the tooth taper was researched. Taking cut parameters into comprehensive consideration, the geometric parameters were designed through the inclination of root line and modified mean point in which machine setting parameters calculated was selected. Only the modified mean point met the meshing equation, and the error of pressure angle would increase as far away from the modified mean point in tooth line. The error would lead to bias in contact. A helical correction motion was introduced and the influence of helical motion coefficient on tooth surface topology was studied. Based on the meshing performance, a suitable coefficient was calculated. Finally, an example was illustrated. The experimental results were consistent with the theoretical analysis. The validity of the proposed method is verified.

Integrated Scheduling Problem on a Single Bounded Batch Machine with an Unavailability Constraint

We consider a scheduling problem where a set of jobs are first processed on a machine with an unavailability interval and, then, delivered to the customer directly. We focus on an integrated schedule of production and distribution such that the sum of the maximum delivery time and total delivery cost is optimized. We study two classes of processing machines in the production part. In the first class, the serial-batch machine, the processing time of a batch is the sum of the processing times of its jobs. In the second class, the parallel-batch machine, the processing time of a batch is the maximum processing time of the jobs contained in the batch. The machine has a fixed capacity, and the jobs are processed in batches under the condition that the total size of the jobs in a batch cannot exceed the machine capacity. Two patterns of job’s processing, i.e., resumable and non-resumable, are considered if it is interrupted by the unavailability interval on the machine. In the distribution part, there are sufficient vehicles with a fixed capacity to deliver the completed jobs. The total size of the completed jobs in one delivery cannot exceed the vehicle capacity. We show that these four problems are NP-hard in the strong sense in which the jobs have the same processing times and arbitrary sizes, and we propose an approximation algorithm for solving these four problems. Moreover, we show that the performance ratio of the algorithm is 2 for the serial-batch machine setting, and the error bound is 71/99 for the parallel-batch machine setting. We also evaluate the performance of the approximation algorithm by the computational results.

Adaptive data-driven modular control approach to computer aided process planning for manufacturing spiral bevel and hypoid gears

Machine setting modification has been an increasingly important access to the accurate flank manufacturing geometric accuracy control for spiral bevel and hypoid gears. More recently, machine setting driven integration of the theoretical design and the actual gear manufacturing is gaining more and more attention. In this paper, the traditional machine setting modification is extended to the case when higher-order component of the prescribed ease-off flank topography is investigated in form of high-order polynomial expression. Moreover, the actual gear manufacturing and general measurement are integrated into an adaptive data-driven high-order machine setting modification. In particular, this modification method is used to perform adaptive modular control for computer aided process planning (CAPP). Here, a data-driven operation and optimization is developed for adaptive high-order modification. It mainly includes: (i) Polynomial fitting and its optimization by using overall interpolation based on energy method, (ii) Data-driven ease-off flank parametrization based on the fastest descent Newton iteration method, (iii) adaptive control strategy by considering the sensitivity analysis, and (iv) Levenberg-Marquardt (L-M) based approximation for high-order machine setting modification. Given numerical test can verify the proposed method.

THE EFFECT OF EXCESSIVE SETTING TIME, LONG DAMAGE OF THE MACHINE, TIME OF PACKAGING PACKAGES STOPPED TO PRODUCTION OPERATIONAL COSTS: STUDY IN LINE 8A PT XYZ FARMA Tbk

This study aims to determine the effect of excess machine setting time, machine breakdown time, time for packaging lines to stop, on production operating costs and which factors are most dominant in influencing production operating costs. This research uses a quantitative descriptive method approach. The place of research is at PT. XYZ Farma on line 8A. The research sample consisted of 22 data records from a population of 450 data records. Data collection techniques are observation techniques, event recording and documentation. The results showed the influence of excessive setting time, machine damage time, packaging line time stalled against operational costs of production. This is demonstrated by using AMOS, the value of C.R (Critical Ratio) exceeds the critical value ± 1,717. The value of C.R for each variable is the excessive machine setting time, the length of time the machine is damaged, and the time of the packaging line has stalled towards the operational cost of production is 2,850; 10, 913; 5,330. Based on AMOS Standardized Regression Weight Output statistical calculations show that the duration of damage to the machine provides the greatest contribution in increasing the operational costs of production. This is indicated by the estimated coefficient value of the largest engine damage time which is 82.1%. So it can be concluded that the influence of excess engine setting time, machine breakdown time and time of the packaging line has stalled to the operational costs of production with the variable length of engine damage giving the greatest contribution.

The Link and Match between the Competency of Vocational High Schools Graduates and the Industry on CAD/ CAM and CNC

This study describes (1) the work process analysis of the production stage in the industry, (2) the required competency and skills of CAD/ CAM and CNC in the industry, (3) the implementation of the basic competency of CAD/ CAM and CNC in vocational high schools, (4) the link and match between the competency of vocational high schools graduates and the industry on CAD/ CAM and CNC. The descriptive-qualitative method was employed by involving 8 people from Mega Andalan Kalasan Ltd (MAK) and 5 people from vocational high schools. The data were collected through observation and interviews which were further analyzed descriptively. The findings indicate (1) the work process analysis map the competencies that must be owned by the workforce including CAD drafter, CAM programmer, and CNC operators in which each workforce involved 4 work process sequences, (2) the competency of CAD/ CAM and CNC described the knowledge and psychomotor activities. In detail, the activity of the CNC machine setting produced knowledge competence and the skills of 36.5% and 26.7% respectively. The operating CNC machine produced the knowledge competence and skills of 25.4% and 23.3% respectively. The 3D drawing and 2D CAD systems produced the knowledge competence and skills of 19% and 23.3% respectively, CAM Programming generated the knowledge competence and skills of 19% and 26.7% respectively, (3) the implementation of basic competencies can be categorized as good, (4) there are two competencies fulfilled the link and match between the vocational high schools' competencies and industry, namely manufacturing drawing competency with CAD as well as mechanical competency with CNC and CAM.

Focused Intensive Care Ultrasound

This book is written for clinicians who are new to ultrasound and those who want to progress further from the basics to more advanced-level scanning. Consequently, it covers a broad range of subjects, and its text is divided into five sections. Section 1 is imaging-based. Chapters in Section 1, such as physics, machine setting, and sonoanatomy, provide the foundation that underpins the rest of the book. Section 2 is structure-based. Chapters in Section 2 cover cardiac, lung, abdominal, and vascular anatomy and enable the reader to start scanning in these areas. Section 3 is problem-based. Chapters in Section 3 cover the major differential diagnoses and algorithmic approaches to ultrasound assessment of the most common clinical presentations, including shock, dyspnoea, trauma, cardiac arrest, sepsis, acute respiratory distress syndrome, and many more. Section 4 is procedure-based. Chapters in Section 4, such as thoracocentesis, lumbar puncture, and percutaneous tracheostomy, cover the technical and non-technical aspects of invasive procedures performed in critically ill patients. Section 5 is governance-based and covers how to deliver a safe and effective service.

Development of Methods to Improve the Mechanical Performance of Coated Grid-Like Non-Crimp Fabrics for Construction Applications

This paper presents investigations aiming to improve the impregnation of a coating agent and thus increase the mechanical performance of geogrids, especially grid-like non-crimp fabrics (NCF) consisting of carbon fiber heavy tows (CFHT). The squeezing process is industry standard, but the relationship between the machine setting parameters (squeezing pressure and hardness of squeeze roll surface) and the impact on the tensile strength of grid-like NCF is still unexplored. The setting parameters evaluated lead to an increase in tensile strength of up to 10% compared to grid-like NCF coated without the squeezing process. Additionally the first insights into the coating process supported by ultrasonic vibrations based on CFHT single yarns are provided. It is shown that the tensile strength of treated CFHT can be increased by up to 12%, in comparison to CFHT coated without ultrasonic vibrations.

Development of a gear drive designer software

The paper deals with the programming and introducing the function of a new program for designing gear drives. The main goal of the program is to provide the exact machine setting parameters for producing a given gear drive. The software is a multi purpose tool for fast industrial calculations and pre-analysis.