Machine Production Cost Research Articles

Investigating equipment productivity in feeder road maintenance in Uganda

Rural roads form the largest part of Uganda’s road network (approximately 50.2%) and is therefore a critical part of economic growth in an agriculturally dependent country like Uganda. With Uganda’s rural population standing at approximately 76% of the total population and agriculture still employing approximately 72% of Uganda’s population, this underscores the need to fix loopholes in road maintenance strategies in Uganda with emphasis on rural roads. This study sought to conduct a detailed cost analysis with a view to determining whether productivity is at an optimum for specific road maintenance equipment in Uganda, with emphasis on mechanized agricultural plantation access road maintenance works. Two descriptive research methods were used: observations and case study approach. Control parameters affecting machine production were identified as machine repair costs, maintenance costs, machine depreciation costs, worker’s salaries, machine insurance costs, and machine fuel costs. Machine downtime was mainly affected by delays in procuring spares. The total hourly machine production costs were calculated to be 699,602 Ugx (185.84USD). This cost calculation can be improved upon in subsequent studies. The study recommends the need for an effective centralised electronic database where all feeder road maintenance data is collected, analysed, and recorded.

Speed Adjustment on Variable Frequency Induction Motor Using PLC for Automatic Polishing Machine

PT. ROFENTI KARSA TAMA is a ceramic industry that produces products in the form of ceramics from natural stone which are addressed in Winong GEMPOL Village - MALANG. To produce a perfect ceramic process requires absolutely reliable electrical and mechanical equipment. In an automatic system a frequency converter is used as a speed regulator, because in a manual system using a grinder, the capacity is only 0.57Kw (kilowatts), and the production effect is not good. Therefore, the purpose of this study is to design an automatic polishing machine using a PLC-based converter. Based on the PLC, the capacity is 5 or 5 Kw (kilowatts). This system can increase ceramic output and improve quality. In this case, assuming that the operator usually uses an automatic system to complete the work of the three operators, the polishing machine production costs can be reduced. Through system improvement, production quality can be improved, manual polishing operators can only produce 480 pieces per day, while the automatic system can produce 1,536 pieces. One day, the polishing operator will save production costs of Rp 2.7 million per month.

The Impact of Felling Method, Bunch Size, Slope Degree and Skidding Area on Productivity and Costs of Skidding in a Eucalyptus Plantation

Grapple skidder is a machine designed for the extraction of tree bunches after felling. Several factors influence its technical performance and costs such as terrain slope, operator experience time, machine type, and the size of tree bunches for each operating cycle, among others. Thus, it becomes necessary to weigh the variables that most influence the productivity and costs of the grapple skidder. So, the main objective was evaluated according to the influence of bunch size using two feller bunchers with distinct technical characteristics, two slope classes and two skidding areas on the productivity and machine production cost in a Eucalyptus plantation. For the analysis of the productivity, the study of time and method was applied and the scheduled machine cost per hour was based on the Food and Agriculture Organization of the United Nations methods. When analyzing the results, it was found that the operational elements moving without load (MWoL) and moving with load (MWL) were the ones that spend the most time in the operational cycle of the grapple skidder. Among the cost components, monetary expenditure on fuel and operator labor were the most influential in the scheduled machine cost per hour. In conclusion, the tree bunches and slope class influenced the productivity and, consequently, the cost of the skidding operation.

Design and Construction of Densification Machine for Vegetables in Rural Settlements

This research work was carried out to improve the storage space and effective handling of dried vegetables specifically tomatoes, onion and okra, for consumers and marketers. The machine basically consists of an upper compression plate, machine mould, piston, lower compression plate and a 3-tons hydraulic jack. The machine performance was evaluated based on Output Capacity and Machine Compression Efficiency. The results showed that the machine output capacity and efficiency were 0.291 kg/h and 96.3%, respectively. The machine production cost stood at N35,000.00 only. The machine is therefore recommended to farmers.

A Benders decomposition approach to the weighted number of tardy jobs scheduling problem on unrelated parallel machines with production costs

This paper addresses the problem of scheduling on-time jobs on unrelated parallel machines with machine production costs. The objective is to maximise the net profit which is the sum of the weights of on-time jobs and the cost of using the machines. This scheduling problem is very important and frequent in industrial settings. It is herein solved using an exact approach that applies Benders decomposition to obtain tight upper and lower bounds and uses the bounds within a branch and bound. The computational investigation shows the efficacy of the approach in solving large instances. Most importantly, the proposed approach provides a new venue for solving large-scale scheduling problems.

A Multi-Actuator Displacement-Controlled System with Pump Switching–

Displacement-controlled (DC) actuation has been under investigation by the authors’ group since its conception in 1998 as a highly efficient alternative to its valve controlled counterpart. The major advantages of DC actuation include the complete elimination of losses due to resistive control and the recuperation of energy due to overriding loads. One obstacle for the introduction of DC actuation to the market is the increased machine production costs due to the one-pump-peractuator requirement. To overcome this impediment, the authors’ research group propose the idea of pump switching. The idea consists on utilizing a distributing manifold comprising a set of on/off valves utilized to direct flow either from/to a hydraulic unit to/from a particular actuator. Then, the concept allows for the reduction of machine installed pump power for multi-actuator machines, thereby minimizing parasitic losses and production costs. In this paper, the challenges and implications, as well as the control strategies developed to realize this technology are outlined for a multi-actuator system. Furthermore, an extension of work previously proposed by the author’s research group is made by presenting a validation of the proposed control strategies on an excavator prototype. Measurement results show that the pump switching concept is attainable while maintaining the same basic DC concept and relatively simple actuator-level control algorithms.

Comparing Productivity and Costs of Three Subgrading Machines

Production rates and costs of three forest road construction machines (Ford County 1164 tractor, D4D and D6D Caterpillar bulldozers) were analysed and compared. Results showed that differences in production rates were attributed mainly by the type and the size of the machine, driver's working experience and the nature of the terrain side slope. Compared to other subgrade productivity studies, machine production rates found in this study were considered to be reasonably high. The mean production rates for the D6D, D4D and the County tractor were 129.0 m3/h, 41.0 mVh and 28.1 mVh respectively. High productive time, easily workable soils and few obstacles encountered during earthworks operation were the major factors which contributed to high machine production rates. Cost analysis showed that the higher the machine production rate the lower the subgrading cost and vice versa. The mean production costs for the D6D, D4D and the County were estimated to be US$ 0.49/m3, US$0.79/m3 and US$0.76 /m3 respectively. The estimated machine production costs were more or less the same as those estimated elsewhere. Although low machine production cost is usually the criterion used in choosing the machine to be used for road construction works, this paper recommends that other factors be considered.