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Coal hauling activities are an important part of mining operation because they affect production continuity, cycle time efficiency, and operational safety. This study aims to analyze the requirements of road support equipment on the coal hauling road from Sector 4 to the new Coal Processing Plant (CPP) at PT. Asmin Bara Bronang, Central Kalimantan. Based on road geometry, traffic density, California Bearing Ratio (CBR), and Unsurfaced Road Condition Index (URCI). The research method used was applied research with a quantitative approach. Primary data ware collected through field measurements consisting of road geometri observations, traffic density observations, Dynamic Cone Penetrometer (DCP) testing to obtain CBR values, and road surface condition assessment using the URCI method. Secondary data were obtained from the company records. The results showed that the hauling road has a total length of 9.1 km with an average width of 16 m, and grade values ranging from -7.68% to 10.52%, which are still below the maximum standard of 12%. Traffic density reached 184 dump trucks/day, for coal hauling and 62 units/day for construction material transportation, indicating high traffic intensity. CBR values ranged from 7% to 100%, showing variations in subgrade bearing capacity. The URCI value ranged from 72,50 to 91.00, indicating fair to good road conditions. Based on the analysis of road conditions and maintenance area requirements, the recommended support equipment for maintaining the hauling road consists of 1 motor grader unit, 1 compactor unit, 1 bulldozer unit, and 1 water truck unit.

The evaluation of haul road geometry at PT Trubaindo Coal Mining was conducted to ensure that the haul road from the stockroom to the jetty meets applicable technical standards, thereby supporting the smoothness, safety, and efficiency of coal transportation activities. This study aims to analyze the conformity of haul road geometric parameters, including straight road width, curve width, curve radius, cross slope, longitudinal grade, and superelevation, based on the standards of AASHTO 7th Edition and Kepmen 1827 of 2018. The research method employed field measurements using a Terrestrial Laser Scanner (TLS), followed by data processing using Maptek and Surpac software. The obtained data were then compared with the applicable standards to determine the level of conformity of the haul road geometry. Based on field measurements, the average values obtained were 14.99 m for straight road width, 18.45 m for curve width, 0.22 m for cross slope, 6.97% for grade, 223.51 m for curve radius, and 1.40 m for superelevation. Furthermore, based on calculations and analysis referring to AASHTO 7th Edition and Kepmen 1827 of 2018, and considering the largest haulage equipment used (Volvo FMX 480), the ideal haul road geometry values were determined as follows: 13 m for straight road width, 17 m for curve width, 124 m for curve radius, 0.26 m for cross slope, 1 m for superelevation, and 6% for grade based on PT Trubaindo Coal Mining standards.

This study is motivated by the discrepancy between production targets and actual field performance caused by dynamic operational conditions, such as equipment productivity and effective working time. The objective of this research is to redesign the production target and develop a more realistic mine sequence using a rolling plan approach at Pit Hill16. The method includes analyzing the productivity of loading and hauling equipment based on cycle time data, calculating effective working time, and determining production targets using the rolling plan method. Furthermore, mine sequence design is developed based on the adjusted production targets. The results indicate that the productivity of loading equipment is 241.98 BCM/hour for the EC480DL excavator and 123.27 BCM/hour for the EC210DL excavator, while hauling equipment productivity is 40.24 BCM/hour. The April production target based on the rolling plan is 275,913 BCM, which can be achieved through mine sequence design with a volume of 277,839 BCM, resulting in a difference of +1,926 BCM, still within acceptable planning tolerance. Therefore, the rolling plan approach is proven to produce a more adaptive and realistic mining plan under actual field conditions.

This study was conducted at PT. Asmin Bara Bronang, Sepan Uring Village, Kapuas Tengah District, Kapuas Regency, Central Kalimantan Province, with the aim of analyzing the productivity and influencing factors of the PC 300 excavator in coal getting activities to support the achievement of production targets. The objective of this research is to analyze the actual productivity and the factors affecting it in Sector 7 coal getting operations. The research method used field observation with a quantitative descriptive analysis approach. The results show that the productivity of the PC 300 excavator ranges from 127.12 to 224.29 tons/hour, with an average of 173.98 tons/hour. In several conditions, the productivity is still below the company’s target of 180 tons/hour. The analysis indicates that productivity is influenced by material conditions, particularly the Hardgrove Grindability Index (HGI) value of 47, which reflects relatively harder material with coarser particle size, and a moisture content of 22.71%, causing the material to be sticky and cohesive, thereby affecting the bucket filling process. In addition, operational factors such as bottom loading patterns, limited number of tailgate dump trucks, and suboptimal selection of dump truck types also contribute to productivity performance.  Based on the findings, it can be concluded that the productivity of the PC 300 excavator has not consistently met the company’s target. Therefore, improvement efforts are required, including the implementation of top loading methods, increasing the number of tailgate dump trucks, optimizing the selection of hauling equipment, and controlling material conditions that affect the digging process.    

The implementation of corporate zakat in Indonesia remains relatively low despite its significant potential to support national economic development. This study aims to analyze the strategic role of corporate zakat as an instrument for reducing tax burdens and its contribution to economic equality. This research employs a literature review approach by examining relevant academic sources. The findings indicate that corporate zakat of 2.5% is obligatory for business entities that meet the nisab and haul requirements. Based on Law No. 23 of 2011 and Law No. 36 of 2008, zakat distributed through authorized institutions such as BAZNAS or LAZ can be deducted from taxable income. Corporate zakat not only fulfills religious obligations but also plays a vital role in wealth redistribution through social assistance and productive capital for mustahik. Therefore, optimizing corporate zakat can serve as a strategic instrument to promote sustainable economic justice in Indonesia. Effective policies and outreach from the government are also needed so that companies are more encouraged to pay zakat in a timely and transparent manner.

Problems in the transmission box of the Drilling Machine 438-02-814-0925 type (0.75 HP, 230/400V, 1425 rpm, produced in 1988) are the degradation of mechanical components for the pulley, V-belt, and rolling bearing. The purpose of maintenance and repair planning is to obtain maintenance costs, maintenance schedules in the period 2026, and the ratio of maintenance costs to profits. The maintenance and repair planning method includes collecting previous maintenance data; application of the inspection-replace-repair-overhaul (IRRO) method; evaluation of the working conditions of components, especially on the pulley, V-belt, spindle pulley (driven pulley), and rolling bearing; prediction of component service life; prediction of repairman costs; prediction of supporting equipment that will be used in maintenance; prediction of spare part replacement time or reinstallation of components after repair; estimation of maintenance and repair costs in 2026; and calculation of the ratio of maintenance costs to profits. The results of maintenance and repair planning obtained maintenance costs in 2026 amounting to Rp 4,627,000 with an estimated Drilling Machine rental rate of Rp 75,000/hour which has the opportunity to be rented for 400 hours/year, and a maintenance cost to profit ratio of 15.42% which implies that the Drilling Machine still has the opportunity to generate profits and is suitable for use in the coming years.

Mining operations rely heavily on the performance and reliability of heavy equipment used in the production process. One of the most important hauling units in open-pit mining is the dump truck, which functions to transport overburden and coal from the mining front to disposal areas. Due to high operational intensity, dump trucks require effective maintenance management to ensure equipment reliability and reduce unexpected downtime. However, maintenance activities are often carried out based only on routine service schedules without analytical planning based on historical data. This study aims to analyze the implementation of forecasting methods in maintenance management to improve the effectiveness of dump truck maintenance planning in mining operations. The research was conducted during field work practice at PT Putra Perkasa Abadi Jobsite BIB, Tanah Bumbu, South Kalimantan. The data used were historical maintenance records of dump truck units obtained from the maintenance department. The research method used a quantitative approach with time series forecasting analysis to identify maintenance patterns and estimate future maintenance needs. The results show that forecasting-based maintenance planning can help companies predict maintenance requirements more accurately and prepare maintenance resources more efficiently. Furthermore, the implementation of forecasting methods can reduce unexpected equipment failures and support operational efficiency in mining activities.

The decline in the performance of the die casting machine in 1998 after a long period of producing copper terminals showed dimensional defects and instability in product quality, especially in nozzle clogging, reduced copper flow, crust buildup on the gooseneck, plunger movement obstruction, and hydraulic pressure leaks. The purpose of planning the replacement and repair of die-casting machine components is to obtain replacement and repair costs, replacement and repair schedules for the period 2026, and the ratio of maintenance costs to profits. The replacement and repair planning method includes collecting previous maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component conditions, predicting component service life, predicting labor costs, predicting supporting equipment to be used in maintenance, predicting the time to replace spare parts or reinstall repaired components, estimating replacement and repair costs for the period 2026, and calculating the ratio of replacement and repair costs to profits. The planning results obtained replacement and repair costs for the 2026 period are 75.770.000,- IDR with an estimated die casting machine rental rate of  1,500,000 IDR/hour which has the potential to be rented for 1,200 hours/year, and the ratio of maintenance costs to profits is 10,02 % which implies that the die casting machine with a capacity of 40 units/hour is still suitable for use and has the prospect of generating profits for the next few years.

The problem with a 4-stroke gasoline engine-driven electric generator is a decrease in tool performance due to wear on important components for the stator, cooling fan, air filter, oil filter, and gasket. The purpose of component replacement planning is to obtain replacement costs, maintenance schedules in 2027, and the ratio of maintenance costs to profits. The component replacement planning method includes collecting maintenance data from previous years, applying the inspection-replace-repair-overhaul (IRRO) method, assessing component conditions, predicting component lifespan, predicting labor costs, predicting supporting equipment to be used in maintenance, predicting spare part replacement times, predicting maintenance costs in 2027, and calculating the ratio of maintenance costs to profits. The results of the replacement planning obtained maintenance costs in 2027 amounting to IDR 570,007,- with an estimated electric generator rental rate of IDR 30,000,-/hour which has the potential to be rented for 128 hours/year, a profit of IDR 3,840,000,- was obtained, and the ratio of maintenance costs to profits was 14.84% which implies that a 2.5 kW electric generator that uses gasoline-pertalite fuel of around 1.5 liters/hour at maximum power is still suitable for use in the next few years and has the potential to generate profits.

The problem with a passenger car with a capacity of 15 people lies in its unscheduled maintenance and having broken down on the road. The purpose of component replacement planning is to obtain component replacement costs, maintenance and repair schedules for the 2026 period, and the maintenance cost-to-profit ratio. The planning method includes collecting previous maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component conditions, estimating component lifespan, estimating labor costs, estimating supporting equipment to be used in maintenance, estimating the time to replace spare parts or reinstall repaired components, estimating maintenance and repair costs for the 2026 period, and calculating the maintenance cost-to-profit ratio. The results of component replacement planning obtained costs for the 2026 period are IDR 11,780,000 with an estimated passenger car rental rate of IDR 800,000/24 ​​hours (day) which has the potential to be rented for 4,320 hours/year, and the ratio of maintenance costs to profits is 10.33% which implies that passenger cars with a capacity of 15 people are still prospective to generate profits and are suitable for use for the next few years.  

Unexpected downtime of a 2 kg/hour coffee grinder is crucial in cafe operations, thus less guaranteeing the availability of the grinder. The purpose of component replacement and repair planning is to obtain a prediction of the maintenance and repair schedule and costs in the 2026 period. The component replacement planning method includes collecting previous maintenance and repair data, applying the inspection-replace-repair-overhaul (IRRO) method, assessing component conditions, predicting component life, predicting technician costs, predicting supporting work equipment and supporting materials to be used in maintenance, predicting the time to replace spare parts or reinstall components after repair, estimating maintenance and repair costs for the 2026 period, and calculating the ratio of maintenance costs to profits. The results of component replacement and repair planning obtained maintenance costs for the 2026 period are IDR 2,350,000, - with an estimated coffee grinder rental rate of IDR 25,000/hour which has the potential to be rented for 1440 hours/year, and the ratio of maintenance costs to profits is 6.5% which implies that the coffee grinder with a capacity of 2 kg / hour is still suitable for use for the next few years and still has the opportunity to make a profit.

Overburden removal at Pit B did not meet the production targets for June and July 2025, which were set at 570,698.8 BCM and 400,986.56 BCM, respectively, while the actual production achieved was 507,071.66 BCM and 312,128.23 BCM. This study aims to determine the theoretical productivity of loading and hauling equipment and to identify the factors that hinder the achievement of production targets. The primary data used in this study include the cycle time of loading equipment, the cycle time of hauling equipment, bucket fill factor, and delay time. The secondary data required consist of swell factor, number of passes, bucket capacity, and available working time. The productivity of the loading equipment was 332.58 BCM/hour, while the hauling equipment achieved a productivity of 53.16 BCM/hour, with a match factor of 0.74. This indicates that the loading equipment experienced waiting time during loading operations due to the hauling equipment not operating optimally or at full capacity. The factors inhibiting the achievement of production targets include a narrow, waterlogged, and uneven working face; hard overburden material; a road grade of 16%, which exceeds the standard maximum of 12%; a curve road width of 15 m, which is less than the ideal minimum width of 19.95 m; undulating haul roads; narrow haul road width; and dusty road conditions.

Overburden stripping operations in the coal mining industry require optimal performance of loading and hauling equipment to achieve production efficiency. This study aims to evaluate the performance of loading and hauling equipment using the Match Factor method in overburden stripping operations at PT Bumi Artlantis Raya. The results indicate that the equipment combination achieved a Match Factor of 0.85, reflecting moderate compatibility with a potential efficiency improvement of 15%. The actual productivity of Excavator 4002 reached 137.02 bcm/hour (91.35% of the 150 bcm/hour target), while Excavator 4004 exceeded the target with a productivity of 195.73 bcm/hour (130.49% of the target). In contrast, dump truck productivity remained relatively low (Mercedes dump truck: 35.58 bcm/hour; Hino dump truck: 35.40 bcm/hour), primarily due to waiting time during loading and disposal activities. Statistical analysis reveals a strong negative correlation between cycle time and productivity (R² = 0.9929). The optimal cycle time to achieve a Match Factor of 0.80 is 969 seconds, corresponding to an optimal hauling distance of 5.38–6.725 km. Although mechanical availability and physical availability were high (94–100%), the use of availability and effective utilization were relatively low due to an imbalance between loading and hauling equipment. This study concludes that improving equipment coordination, increasing bucket fill factor, enhancing haul road conditions, and implementing preventive maintenance are essential to achieving more optimal operational efficiency in overburden stripping activities.

The problem faced is the decline in the performance of a 650 liter/minute centrifugal pump due to wear on components, especially the impeller, rolling bearings, and mechanical seals in supplying process water and clean water in industrial production systems. The planning objective is to obtain a maintenance schedule for a 650 liter/minute centrifugal pump for the operational period of 2026 and the ratio between maintenance costs and profits generated by the machine. The maintenance planning method includes collecting maintenance data from previous maintenance periods, reviewing centrifugal pump specifications, applying the inspection, replace, repair, and overhaul (IRRO) approach, estimating the age and price of components that are expected to be damaged, estimating the cost and duration of dismantling and installing components that have been repaired in accordance with the provisions of the requirements for usable components or replacement parts, scheduling maintenance and repairs, estimating maintenance and repair costs for the 2026 period, and determining the ratio of maintenance costs to profits. The planning results are in the form of a maintenance schedule for the 2026 period worth IDR 4,290,000,-, a maintenance cost to profit ratio of 7.44% and the implications indicate that the machine is still suitable for use and prospective for operations in the next few years.  

The problem with the coconut grater machine is that the machine has decreased performance after being used for several years, especially in the mechanical components (electric motor, V belt, Pulley, grater knife, hopper) and its electricity. The purpose of maintenance and repair planning is to obtain costs, maintenance and repair schedules for the period 2026, and the ratio of maintenance costs to profit. The maintenance and repair planning method includes collecting previous maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component conditions, predicting component lifespan, predicting labor costs, predicting supporting equipment that will be used in maintenance, predicting the time to replace spare parts or reinstall repaired components, estimating maintenance and repair costs for the 2026 period, and calculating the maintenance cost to profit ratio. The results of maintenance and repair planning obtained maintenance costs for the 2026 period were IDR 957,000 with an estimated coconut grater machine rental rate of IDR 10,000/hour which has the potential to be rented for 900 hours/year, and the maintenance cost to profit ratio was 10.6% which implies that the coconut grater machine with a capacity of 15 kg/hour is still prospective and feasible to use for the next few years.

Coal quality must be controlled from the pit area to the ROM stockpile to ensure compliance with market specifications. However, hauling and stockpiling processes often lead to changes in coal characteristics. This study aims to analyze variations in proximate parameters between coal from Pit B1 and ROM Stockpile Km4 at PT Trisensa Mineral Utama and to identify factors contributing to these changes. The methodology includes field sampling at both locations, sample preparation based on ASTM standards, and laboratory testing of inherent moisture, residual moisture, ash content, volatile matter, and fixed carbon. The results indicate that coal undergoes quality changes after being stored in the stockpile, marked by a decrease in inherent moisture of 2.54% (from 17.64% to 15.10%), a decrease in residual moisture of 1.42% (from 17.17% to 15.75%), a slight reduction in ash content of 0.16%, a decline in volatile matter of 0.28%, and a reduction in fixed carbon of 0.18%. These changes are influenced by field conditions, material contamination during mining, rainfall, coal porosity, and handling activities at the stockpile. The findings highlight the need for improved sampling management, better surface water control, and stricter material handling procedures to minimize coal quality degradation.

Frequent damage to the grinding disc components and the transmission system of the 15 kg/hour rice flour grinder is a problem faced. The purpose of scheduling component maintenance and repairs is to obtain predictions of maintenance and repair schedules and costs for the period 2026. The component maintenance and repair scheduling method includes examining previous period maintenance and repair data, applying the inspection-replace-repair-overhaul (IRRO) method, assessing component conditions, estimating component life, estimating technician costs, estimating supporting work equipment and supporting materials to be used in maintenance, estimating the time for replacing spare parts or reinstalling components after repair, estimating maintenance and repair costs in 2026, and calculating the maintenance cost to profit ratio. The results of component maintenance and repair scheduling show that the maintenance cost in 2026 is Rp 1,370,000,- with an estimated annual profit potential of Rp 21,600,000, and the maintenance cost to profit ratio is 6.3%, which implies that the 15 kg/hour rice flour grinder is still quite prospective and feasible to use for the next few years.

Progressive wear on drive belt components, brake lining thickness, double lining bowl and other components of continuously variable transmission (CVT) on 160 cm3 automatic motorcycles are the problems faced. The purpose of component replacement planning is to obtain maintenance costs in 2026 and maintenance to profit ratio. The component replacement planning method includes collecting previous maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component conditions, predicting component lifespan, predicting labor costs, predicting supporting equipment and supporting materials to be used in maintenance, predicting spare part replacement time, predicting maintenance costs in 2026, and calculating the maintenance cost to profit ratio. The results of component replacement planning obtained maintenance costs in 2026 are IDR 8.151.667,- with an estimated rental rate for Automatic Motorcycles of IDR 12,500/hour which has the potential to be rented for 3960 hours/year, and the ratio of maintenance costs to profits is 16.4% which implies that the 160 cm3 Automatic Motorcycle which was first used in 2021 is still prospective to generate profits and is suitable for use in the coming years.

The problem with the sugarcane press machine is a decrease in performance in sugarcane pressing because it has been used since 2020 with an initial price of IDR 3,000,000, which is predicted to be IDR 5,500,000 in 2025 which occurs in the main components of the roler mill, V-belt, and bearings. The purpose of scheduling replacements and repairs is to obtain a schedule, estimated maintenance costs, and the ratio of replacement and repair costs to the profit of renting a sugarcane press for the period 2026. The scheduling method includes collecting data on the use of the sugarcane press machine, a list of replacements for 5 components for roler mills, V-belts, bearings, gasoline motor tanks, and engine frames from 34 components, component prices, estimated labor costs, equipment costs, supporting material costs, application of the inspection, replace, repair, and overhaul (IRRO) method, scheduling replacements and repairs, and calculating the ratio of replacement costs to profits. The results of the replacement and repair scheduling are in the form of maintenance costs of IDR 958,000, with a rate of IDR 10,000/hour for 588 hours/year, resulting in a profit of IDR 5,880,000, and a ratio of maintenance and repair costs to profit of 0.16%.

Problems in the meatball dough grinder are low production, increasing maintenance costs and disappointed meatball dough customers who receive orders late due to problems with the electric motor, Pulley, V belt, cutting knife. The purpose of the replacement scheduling is to obtain costs, maintenance-repair schedules in the period 2026, and the ratio of maintenance costs to profits. The replacement scheduling method includes collecting previous period maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component working conditions, predicting component life, predicting repairman costs, predicting supporting equipment that will be used in maintenance, predicting the time to replace spare parts or reinstall components after repair, estimating maintenance and repair costs in 2026, and calculating the ratio of maintenance costs to profits. The results of the replacement scheduling show that the maintenance costs in 2026 are IDR 2,530,000 with an estimated rental rate for the meatball dough grinder of IDR 10,000/kg which has the potential to be rented for 1300 hours/year, and the ratio of maintenance costs to profits is 4.9% which implies that the meatball dough grinder with a capacity of 5 kg/hour still has the potential to sell well and is suitable for use in the coming years.