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Continuous improvement equals productivity, efficiency

One way to stimulate productivity and efficiency in quarrying operations is to have real control and understanding of the production versus the plan. Operations can analyse trends to justify process changes and understand the best working practices for every activity from quarry to plant to final product. This process of reconciliation allows management to make the right decisions at the right time.
By adopting a Plan > Do > Check > Act > Plan cycle (see Figure 1), operations will naturally increase performance as they foster a cycle of continuous improvement. The cycle starts with the planning data, known as the ?Plan? stage. This planning data could be the grade/quality that was planned in the geological model, or the number of tonnes that were planned to be hauled during a shift. This plan is then executed during the ?Do? phase. 
Data is recorded during the activity, for example, on the plod sheet in the trucks. This actual data can then be compared against the planning data to establish the variance, known as the ?Check? stage, which is discussed below. Once any variance is established, acting on the discrepancy will ensure it does not happen again. This approach allows continuous improvement to be adopted and reduction in variance over time.
Many in the industry often struggle at the end of every month to compile and validate production data when reconciling. Often the figures between quarry production and the plant production do not match and one or both departments are required to make adjustments. Typically, this involves multiple spreadsheets with little data validation and disparate data share. 
The fact spreadsheets are used so widely throughout the industry often results in lack of data integrity or security, human errors and a slow end of month process and bottlenecks. There is a large amount of time spent preparing data in which, ultimately, there is little confidence. Also, the management of the discrepancies between claimed and actual is difficult. Operations must then understand the causes of the differences.
DRIVING EFFICIENCY
Technology exists to provide managers at the quarry and corporate levels with better visibility of the operations. Technology systems give operations the tools they need to drive productivity and efficiency. The Dassault Syst?mes GEOVIA brand?s reconciliation adviser for Europe George Long says there are four simple steps to follow when looking to have better control in the short term. These are as follows: 
Step 1 ? Consolidate your data
To have visibility of the actual production versus plan, all data needs to be in one place. Data should be captured either manually or automatically through interfaces with existing third party systems such as geological databases or automatic data capture from machinery through fleet management systems or SCADA systems. Budget and forecast information should be uploaded and kept up to date as appropriate.
Step 2 ? Validate the data
Ensure the quality of the information entered. Reject erroneous data and have a workflow sign-off of the previous raw data. When poor quality data is accepted, it will affect all subsequent downstream processes and analytics that utilise it.
Step 3 ? Report regularly
Daily production, stockpile balances, monthly production, equipment performance, costings, employee activities and other key measures should all be reported on a regular basis. Reports should be generated and distributed automatically, enabling employees to analyse and react to the findings faster.
Step 4 ? Capture more data
By capturing more data, and more details about your operation, you will have more intelligence with which to make decisions to improve productivity and efficiencies. The more you know, the better control you have. 
RECONCILIATION ? WHERE NEXT?
The definition of reconciliation can vary considerably from country to country, site to site and role to role. The process can be used for material balance across the operation, distributing discrepancies in tonnages and grades/qualities back to certain movements or activities in the operation. Other operations use the term ?reconciliation? for their production accounting. However, it is most commonly used to compare planned and actual data. When it comes to reconciliation, there are two important questions to ask: why is the process undertaken? And what is done with the results? 
Traditional reconciliation involves a retrospective analysis of the operation?s performance. This analysis often leads the quarry to impose certain corrective factors, which are taken forward to improve future plans. The typical reconciliation procedure for a mining operation is a month-end process, which validates and approves the production figures for the month against what was planned during that period. The quarry and the plant usually follow a similar procedure and the quarry reports are compared to the plant results. The main purpose is to achieve consistency between the quarry and the plant, to validate assumptions, to check factors such as truck factors and call factors and to assign ?credits? to certain parts of the value chain where necessary. 
These factors are usually established over a long period of time and are often refined over the life of the quarry. The performance of the quarry is indicated by these factors and, in an ideal situation, the planned values would equal actual values. However, the number of variables across the process chain makes this unreasonable. 
The actual process of reconciliation involves redistributing the discrepancy between the planned and the actual across the mining value chain. It is up to the individual operation how this material balance is managed. The mining value chain and discrepancies can be split into individual business units or reconciliation envelopes and distributed across the entire chain. Inputs and outputs from these reconciliation envelopes can be measured and any discrepancies can be manually or automatically distributed across the attributes within that envelope. Reconciliation can be undertaken at any level in a quarry operation including quarry production and plant production at the finest level of detail.
VARIANCE ANALYSIS
The analysis of the variance data is the most important stage of the reconciliation process. By understanding the reason behind the discrepancy, changes can be made to operational processes to reduce the variance next time. As previously discussed, many operations simply calculate the variance and use factors to establish equilibrium in the planned and actual data. 
Simply knowing this variance is not conducive to improvement. The important point is to understand where, why and how this variance occurred and then make adjustments to the figures and to the operations to ensure these discrepancies do not continue. The understanding of the cause of the variance is the key to improving the operational efficiency and reducing the variance next time. 
This kind of analysis of data is invaluable to quarrying operations. 
The industry must analyse the trends to understand the cause of the greatest variance. For example, the operator may notice that a certain piece of equipment consistently has a variance of -20 per cent. Once the operator notices this pattern they begin to look at the different parameters associated with that piece of equipment. The operator orders a change in the load factor used for the machinery, as this parameter was last updated three years ago when the equipment was originally purchased. Immediately, there is an improvement in the variance between the planned and the actual associated with that piece of equipment. 
Closer analyses of variances are a key part of the continuous improvement culture in a quarry operation, something that drives productivity and efficiency in an operation. Technology can aid in gaining control of operations, whether it be operational reporting at quarry level or corporate visibility from head office. ?
Source: GEOVIA
This article originally appeared in the September 2013 issue of Quarry Management (UK) and reappears in Quarry with kind permission.

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