Asset utilization, productivity, fuel consumption per unit of production, operator skills, and site supervisor efficiency are critical for any mining and construction business. But for any owner or CEO of a company, it is not possible to visit the project site frequently and watch how the operations are going on. For quite a long time it was the responsibility of people involved in the execution of the job at site and the project owner/CEO would depend on the feedback and reports given by the site supervisor on asset utilization, performance, fuel consumption etc. But due to various reasons there would be some gap between the ground reality and the information provided. This would lead to some unintentional errors, which would diminish the equipment’s life, and thereby, productivity.
Remote monitoring of asset operations and fleet management
A competitive business environment and government regulations on emission norms have been playing a critical role in continuous upgradation of technology in construction equipment. Remote monitoring of asset operations and fleet management is one such technology which has been of great help for customers in managing their fleet efficiently. People sitting in their office or even travelling can have access to their machines deployed at sites and see their location, their utilization, their fuel consumption, operator behaviour and performance, and the site supervisor’s execution abilities.
The present generation construction and mining machines are equipped with a device which can capture important data from the machines and transmit it to the owner’s mobile phone or computer through mobile or satellite services. This technology by several manufacturers goes by various names such as Product Link and Vision Link (Cat), Care Track (Volvo), Komtrax (Komatsu) and ConSite (Hitachi). It gives data on fuel consumption, asset utilization, idle running, travelling time of crawler machines, mode of operation (excavators), schedule maintenance adherence, and more. Data can be traced for any specified time and period and the status known at the time of access.
Fuel Consumption: Data on fuel consumption can be viewed for an individual machine, a set of machines, or a fleet of machines. The data provides information details with a clear breakup of working hours, idle run time, and overall performance. With this, machine owners can go through the fuel consumption per unit of production of every machine and know the efficiency of the machine operator. In case of considerable difference in fuel consumption, they can investigate possible causes like leakages, fuel system problem, errors in records, fuel theft etc., and the necessary remedial action can be taken. Expenses incurred in fuel consumption is 50 - 60% of the total operating cost, hence, any saving will have a great impact on the overall operating cost.
Idling time: This data gives the percentage of idle run of engine over the total number of work hours. Excessive idling can cause injector dribbling, fuel mixing with lube oil (loss of viscosity), early wear of bearings, release of harmful emissions, wastage of fuel, and even early repairs of the engine. Every litre of diesel burned will release approximately 2.7 kg of CO2 into the atmosphere. Long idling of engine leads to inadequate burning of fuel leading to harmful emissions.
Travelling hours: A hydraulic excavator is designed mainly for material excavation and loading jobs. The crawling mechanism in the machine is used for moving it as the work progresses, or to move it for short distances at the site. An excavator cannot be used like a payloader by shifting it frequently since its undercarriage and final drives are designed for limited and slow speed travel. Excessive or high-speed travelling will lead to early wear and tear of the undercarriage parts and of the final drive gears, leading to increase in operating cost and more downtimes of the machines.
Nowadays, some quarry owners are using custom-made heavy-duty axles fitted with tires for shifting excavators within the same quarry to protect the undercarriage components. The recommended travel hours of a hydraulic excavator are <16%, but it has been noticed that in some jobsites, the crawling hours are as high as 35% of the total run hours. Data obtained through reports helps in identifying the time and the operator responsible and based on this information the owner can take corrective action to reduce the travelling time of his machines.
Mode of operation: Excavators are now provided with multiple modes of operation to facilitate the operator to select the most appropriate mode based on the working conditions at the project site. Mode selection is done through a switch in the operator’s cabin to keep the engine’s RPM at a specified range. But many operators operate the machine at a high RPM under a misconception that a higher RPM will give higher production. This is incorrect since the engine’s torque is also critical during excavating and loading. The torque curve of a diesel engine rises to a certain RPM but starts declining after crossing it. This needs to be explained to the operator so that they can select the most appropriate mode of operation, and thereby also save 6 to 8% of fuel without compromising on the machine’s productivity.
Asset utilization: This is information provided about the available hours and actual run hours of individual machine and total fleet plus the time when the machine was off or on. This report helps in finding reasons behind the machine’s poor utilization, frequent breakdowns, long downtime, excess machine (s) at site, etc. Based on the information, the owner can look for solutions like spare parts planning, trimming the fleet size, discussing the issues with the manufacturer, taking decisions on scrapping the machine, and so on.
Scheduled maintenance: Some machines have the option to monitoring whether the project team is doing the maintenance, such as oil and filter change, as per the specified interval or is the team delaying it. Scheduled maintenance is critical for the desired life of the machines, since any delay in maintenance will lead to premature wear of the assemblies, resulting in machine downtime and expensive repairs.
Asset location: Location can be seen live at any point of time and the owner can also opt for geo fencing. This is mainly useful for fleet deployed on rent. One can see if the machine is working in its designated area or is out of the area.
Operation data can be seen with clear time and date in all the incidents and cannot be hidden by the operators or site supervisors. This data helps in identifying gaps in operator and maintenance team such that the owner can initiate training of the team for efficient operating and maintenance practices.
Case studies of improved operating practices due to remote monitoring
Fuel savings in excavators by running in appropriate mode: In a quarry where 15 excavators of 1.6 Cu. Mtr were deployed, the operators used to run the machines in H mode i.,e high RPM mode for >60% of the time, keeping the idle run @22%. The actual suggested mode is G which is 200 RPM less than H mode. Operators and supervisors were under the assumption that with G mode they will not get the required productivity. After giving classroom and field training and monitoring the mode of operation versus productivity, they realised that G mode is appropriate, and the H mode is to be used only in exceptional conditions. It was noticed that the machine was operated in G mode to the extent of 65%, H mode 10%, Idle 20% and the resultant reduction in fuel consumption was approx. 2 litres per hour in all the 15 excavators. This amounted to `67 lakhs per year (15 machines x 3000 hrs per year x 2 ltr x `75/- per ltr). Imagine the saving if the fleet is large and the size of the machine is bigger.
Excessive crawling of excavators: Based on data, when enquired about the reasons behind excess travel (which was 25 to 35%), the operators said that the machines are being used for shifting some material in the quarry, plus there was unplanned blasting, frequent changes of working face etc. This was controlled with some discipline, team coordination, and pre-planning of the work.
Excessive idle run of machines: Operators revealed silly reasons like usage of trucks and excavators for lighting purpose, long waiting at loading machines, starter motor issues, battery issues, etc. – all of which are avoidable. In a quarry, an 8.5 Cu mtr front end loader’s idle run was brought down from 43% to 20% over a period of two months through regular monitoring and counselling. In same sites, the idle run in dump trucks was brought down by 8% over one month.
It is worthwhile for customers to use this remote monitoring facility by paying a nominal subscription fee. At the same time, the service providers must also explain the benefits and train the field team in optimum use of the monitoring technology. In fact, the real value addition that the service provider brings is by making the customer understand all the features in the machine and how to use them for better productivity and reduced cost of operation. The payback will be customer loyalty.