A Reliability-Centered Maintenance Study for an Individual Section-Forming Machine

This study investigated the breakdown trend in an automated production with an aim to recommend the application of reliability-centered maintenance (RCM) for improved productivity via a new preventive maintenance (PM) program. An individual section-forming machine (ISM)—a glass blowing machine for making glass bottles—was used as the case study for an automated production system. The machine parts and the working mechanisms were analysed with a special focus on methods of processes and procedures. This will enable the ISM maintenance department to run more effectively and achieve its essential goal of ensuring effective machine operation and reduction in machine downtime. In this work, information is provided on the steps and procedures to identify critical components of the ISM using failure modes and effect analysis (FMEA) as a tool to come up with an optimal and efficient maintenance program using the reliability data of the equipment’s functional components. A relationship between the failure rate of the machine components and the maintenance costs was established such that using the recommended PM program demonstrates evidence of an improvement in the machine’s availability, safety, and cost-effectiveness and will result in an increase in the company’s profit margin

Structural Fabrication and Dynamic Simulation of Stress of a Vibrosieve for Efficient Industrial Applications

A reliable and accurate size determination of powder particles or solid particles, in general, depends on the vibrating efficiency of a vibrosieve. Thus, the study employed the inexpensive design concept of vibration mechanics and mass balance to improve the quality production of powder. Stress simulation of a vibrosieve was proposed. The result of the stress simulation using carbon steel materials showed that there is variation in both yield stress and shear stress. For a 7 N load, a yield stress of 2.817– 2.835 N/m2 and a corresponding shear stress of 2.817–2.821 N/m2 were observed. Subsequently, simulation result using alloy steel revealed a yield stress ranging from 6.204 to 6.212 and a corresponding shear stress of 4.549–4.555 N/m2. The variation in the stress depicts the fatigue life of the machine overtime. Thus, the result of increased yield stress showed that the material might likely fail overtime. This will enable designers to carefully select their material and operating stress which will be safe for the machine, thereby increasing machine, reliability and efficiency

Medication use among pregnant women at a secondary health institution: utilisation patterns and predictors of quantity

Background: Despite the lack of adequate studies on the safety of drugs in pregnancy, surprisingly, available evidence shows that pregnant women still take large number of drugs. Objectives: The study aim was to determine drug utilization pattern and predictors of number of medications used by pregnant women. Methods: This was a cross-sectional survey of 369 pregnant women attending a secondary health facility. Data were collected using interviewer-administered questionnaire. Descriptive and inferential statistics using the Chi-Square test were carried out with level of significance set at p<0.05. Results: Three hundred and sixty-nine women were interviewed. Their mean age was 27.7 years (SD\ub1 4.78) and the mean number of pregnancies was 2.46 (SD\ub1 1.34). On average, 2.62 medications were taken, with the lowest being 1 and the highest being 12 different medications during the course of pregnancy. Those who were on more than 2 medications were more likely to be older than 30 years, had lower education and with history of associated medical conditions. All participants were on one form of supplements or the other, nearly half had used antimalarials, 12.8%, 5.8% 2.4% were on antibiotics, anti-hypertensive and anti-retroviral medications respectively. All the medications prescribed were from category A, B, C, N, and none from category D and X. Conclusion: Varieties of medications were used during the course of pregnancy among this population, however, most of these drugs were still within safety profile

Influence of Von Mises Stress on the Deformation behaviour of a Pinion Spur Gear under Cyclic Loading in a Bottling Machine: An Approach for predicting surface Fatigue failure in Gears

Fatigue failure predictions using analytical method have become cumbersome due to the types and mode of load applications on the gear teeth. The study employed a simulation approach to predict the fatigue behaviour of a pinion gear under cyclic loading by the determination of the Von Mises stress which can result to Surface deformation. The simulation was carried out on the gear component with emphasis on the teeth at different interval of 60, 90, 120 and 150 seconds using SolidWorks program. The result showed that increased stress resulted to increased deformation. Thus a minimum and maximum Von Mises stress of 1.303e+001 N/mm2 and 7.370e+001 N/mm2 were observed at 60 seconds against the fracture strength of the chosen material, gray cast iron (276 MPa). Further to this, the equivalent minimum and maximum deformation at 60 and 90 seconds were observed to be 7.192e-004 mm, 2.304e-002 mm at 60 seconds and 1.594e-003 mm,2.365e-002 mm at 90 seconds at the tooth respectively. This implies that deformation increases as stress increased and they are both functions of time. Based on the results of these analysis, Von Mises stress and the cyclic loading played an important role in predicting the deformation behaviour of the pinion gear. Thus, it is worthy of note to say that this concept has reduced the rigorous calculations in analytical method of failure predictions