Ma-estro Srl has recently realised an innovative automated system with production control and maintenance management for the Calcestruzzi spa aggregates processing plant, which is part of the Italcementi Group.

The production unit is in the vicinity of Cagliari in the splendid Sardinia region. It is mainly used in several ready-mix concrete plants, both for use within the Group and for other important customers.

All study, design and management phases have been followed by Mr. Raffaele Piludu, as Technical Manager of the Calcestruzzi spa crushing plants for central and southern Italy.

Mr. Piludu immediately had clear objectives in mind that the system had to guarantee and after careful evaluation Ma-estro Srl l was chosen. This company had presented a complete project, supplying a real management program along with automated plant control.

The plant is made up from a primary washing and selection of natural sands line and another line for crushing, washing and selection of gravels with production of crushed sand. The system manages both production lines, which it displays on two monitors and all of the graphics have been customised to make the system intuitive and user-friendly.

Ma-estro Srl has put its Quarry Control system to work and has allowed to manage the entire plant with the minimum indispensable staff present.

This was an objective to be reached, not only to save money but also to increase safety on site.

"With Quarry Control the need to operate directly on site is drastically reduced; all material controls and dosing are managed automatically".

Regarding software:

Quarry Control is a very flexible system that allows to dialogue with the various modules made available, especially on this plant, if connected:

1. Quarry Production Control is the system used to control production, processing times and energy consumption.
2. Quarry Maintenance Control, used to control routine and extraordinary maintenance and quality controls.
3. Quarry Control Pro used to optimise production, automate the plant start/stop sequences and check all working machines.

Regarding hardware:

Weighing systems for production control
Energy meters for energy consumption and analysis of the electric line
Sonar technology level sensors
Hydrocyclone pressure control
Control of current absorption of all machines
Rotation sensors on all belts
Jamming sensors on channel with high probability of jamming
Washing water level sensors
Control via inverter for all feeders

Description of Quarry Control Pro System

Quarry Control Pro is the software that automates the production process; the system detects the load of the machines present on the plant and determines the correct amount of material that the plant must produce to reach maximum efficiency. The system is usually calibrated on the plant where it is installed. In fact, in this sector it is rare that the problems of one plant are the same as those on another.

Thanks to the experience gained through the years, Ma-estro Srl can adapt all of its solutions to the plant and to the operator using the same. As well as the automatic regulation of the aggregates flow rate, the system monitors all belts and all possible jamming points, which could lead to plant downtimes and pollution of the material produced. This allows the Calcestruzzi SpA plant to work in tranquillity and also without the presence of an operator. In terms of efficiency, the system offers its maximum performance in the presence of a wide array of material, adapting itself to all situations in real time, both in the presence of coarse and sandy material. This allows the plant always to be calibrated specifically on the basis of the features of the natural material. All operating parameters are protected by password and can all be modified by the plant administrator. Calcestruzzi SpA has also adhered to the yearly tele-assistance service program, for rapid interventions when necessary or updating of software.

Quarry Maintenance control allows to monitor all expiry of maintenance and quality control interventions, guaranteeing traceability of all routine and extraordinary interventions carried out on the plant. The system is used on the plant via very simple touch screen graphics, which are user-friendly even for operators that have never used a computer system, and in the office where the data is accessed via web pages for remote control from any position. Quarry Maintenance control also manages all those controls that any quality system requires; the operator views all controls and can make note of any non-conformities. The system records all this information in a powerful database, which can be consulted remotely via web or locally on the plant display.

Maintenance management can be extended to the entire company fleet.

Quarry Maintenance Control allows to record all the technical information regarding the individual machines and all of the various interventions that the operators must perform in order to carry out maintenance.

All expired maintenance interventions or other activities are displayed on the video, sent by e-mail or displayed on web pages. The system automatically generates all interventions to be carried out, with the necessary instructions and printing the intervention sheets. The member of staff assigned to maintenance clearly understands the jobs to be performed immediately, without the possibility of error.

Once the maintenance interventions carried out have been entered, the data is available from any PC connected to internet, via the user-friendly touch screen display. Quarry Maintenance Control is not only useful for monitoring all interventions performed on the individual machines, but also for recording the times and names of the persons performing the individual interventions, thus resulting in maximum traceability of the operations carried out and relative statistics.

Quarry Production control, the plant at Cagliari has been fitted with 3 Pfreundt (a German company that collaborates with Ma-estro srl for many years) conveyor belt weighing systems and three energy meters for consumption analysis and status of the mains electricity network. These communicate all data to the system, which automatically records all production information in tonnes and all energy consumption, calculating the incidence of electricity consumption per tonne produced. Quarry Production Control records all information on the database and allows to export the data in different formats. Moreover, the remote control allows real time monitoring of production or research on historical data. The energy values recorded are divided on the basis of plant use; for example if the plant runs empty without material, energy consumption will be divided into non-productive consumption, thus allowing the plant administrator to determine all energy wasted by the plant day by day. Quarry Production Control automatically processes all data at the end of the day and generates an e-mail that is sent to one or more receivers; the Administrators or staff assigned to controls will automatically receive a very simple and effective report that is used to easily understand production trends. It can be clearly read even by persons that do not understand the production cycle. The system also automatically sends any production anomalies via e-mail, for example a large energy consumption/production ratio, a very low power factor, excessive energy consumption for crushing and much more information regarding anomalies. These warnings sent automatically via mail allow to save precious time when consulting data.

Quarry Control Pro, Quarry Maintenance Control and Quarry Production Control have been inserted into a unique graphical interface, whose complete version can be consulted via web and also on the plant in a simplified version via touch screen monitor; it is also suitable for use by staff without computer skills. It must be remembered that Ma-estro was established due to the personal requirement of management of a quarry in Trentino, therefore the systems offered bear in mind the difficulties of using complicated and sophisticated systems, supplying systems only tested in the mining sector and simple and reliable solutions. The philosophy of Ma-estro Srl is the simplicity and user-friendliness of all systems for all members of staff, even those who have never used computer or automated systems before.

Ma-estro Srl operates in Italy but also abroad. Thanks to modern systems, today it is possible to offer real time services and after-sales assistance also to geographically distant companies!

Interview with Raffaele Piludu, Calcestruzzi Spa Manager:

The production of a crushing and selection plant is often greatly affected by the "man-plant engineer" factor, who is inclined to calibrate the infeed flow rate on average or even low values with respect to the effective potential of the plant, in order to prevent undesired jamming or overloading.

As well as the classic operating safety devices and controls, thanks to continuous control of the weighing system, the automation adopted allows to guarantee an average hourly production that is pre-established and studied regarding the effective maximum capacity of the machines present in the plant, relieving the plant engineer of many "responsibilities" and allowing us to understand the real limits of the machinery.

Amongst other things, this system has allowed us to establish, with numbers available, the incidence of energy that can easily double its unit incidence value in the event of low process feeding with respect to the real capacities of the assembly, with obvious worsening of average production costs (Kw/ton).

The reports supplied by the system, and which I receive by e-mail every evening, are of paramount importance for keeping production and efficiency of the entire site under control as we have a daily production report and can thoroughly examine any problems causing plant downtimes in real time.

Out plant engineer Massimiliano Broccia is also enthusiastic about the advantages offered by the automation and control system, which allows him a free hand on site and otherwise unthinkable peace of mind.

Massimiliano is also enthusiastic about the reports, which give him the possibility to quantify the work daily, sharing this information with other colleagues that move around the site.

This awareness creates a very positive spirit of competition. In fact, this pushes the team towards improvement, like a game, always looking to produce that extra tonne!!

Raffaele Piludu