As the market becomes more competitive with more companies fighting for market share and increasing customer expectations, furniture manufacturers have to continue to find new ways to cut costs and increase profit margins. Total Autonomous Maintenance can decrease downtime and improve overall production efficiency. By Sara Miranda and Isabel Lopes, IAENG.

The competition between companies has been intensifying over the years. In this global economic crisis environment, this factor plays an even more crucial role in the performance of companies.

A few years ago, the concept of competitiveness was almost non-existent. However, over time the existence of new companies made the market more complex, causing consumers to be more demanding in all aspects.

The existence of a large number of competitors in the same area requires business to adopt new tools and methodologies that allow remaining competitive and sustainable in the market. The application of effective methodologies is essential so that they achieve success. To achieve the expected competitiveness, and the best possible results, companies tend to adopt methodologies for continuous improvement. Studies indicate that the application of continuous improvement methodologies combined with a good human resource management can significantly increase the performance of an industry.

One of the methodology that has been recognised as a strategic weapon to increase the productive performance of companies is Total Productive Maintenance, which has been applied successfully in many companies.

Maintenance was initially seen by many companies as a necessary evil that should only be performed when absolutely necessary. However, with the growth of markets, increasing competitiveness, and the development of new production paradigms, the maintenance concept has evolved.

Following this evolution, came the concept of Total Productive Maintenance (TPM). This methodology originated in Japan and isconsidered an evolution of the concept to preventive maintenance that emerged in the US. TPM is a methodology that aims to increase the availability of existing equipment, and thus reduce the need or more capital investments, allowing companies a break in their budgets.

TPM is supported by eight pillars that define it, namely: autonomous maintenance, planned maintenance, targeted improvements, education and training, quality maintenance, new equipment management, administrative TPM, and the last pillar health, safety and hygiene.

Among the various TPM pillars, there is one that is the cornerstone of this methodology, the autonomous maintenance. This pillar stands out in that it includes a series of systematic work to be performed frequently.

In autonomous maintenance, the operator must be involved in the maintenance of equipment and is responsible for taking care of it, performing minor repairs and suggesting improvements that reduce failures and/or its consequences. To endow operators with knowledge about their equipment is a way to maximise their efficiency. Good management and effective maintenance policy can influence the productivity and profitability of a production process, and maintenance can now be seen as a profit generating function and not as a cost centre.

Productive Maintenance

TPM is defined as the productive maintenance performed by all employees who perform activities in small groups, and can be seen as the performance of service integrating the entire company. This means that the TPM is a maintenance methodology developed with the participation of everyone from employees, service technicians, including supervisors.

TPM is supported by a set of pillars that define and enable their implementation. Autonomous maintenance is considered one of the most important pillars in TPM philosophy. The autonomous maintenance consists in performing small maintenance activities that are performed by the employees responsible for each machine, there by distinguishing TPM of any other type of philosophy.

In autonomous maintenance, it is intended to develop a set of skills in employees so that they easily dominate their equipment, sensing its first signs of wear, misfits,leakage or even parts loose, being able to easily suggestimprovements needed to eliminate these losses.The implementation of the first pillar, autonomousmaintenance, also called first level maintenance, providesthe basic foundation for the implementation of the otherpillars.

The main goal of autonomous maintenance is to reducethe number of equipment failures, and for that purposeemployees should eliminate the anomalies of the machines.These anomalies are seen as minor flaws, abnormaloperation of the equipment or even small errors that may appear on their machines.

Maintenance Management

In the company under study, several tasks of preventive maintenance are monthly planned. This planning is of utmost importance so that in the short time planned for maintenance operations, all procedures necessary for the proper operation of the equipment should be completed since the plant works 24 hours a day.

Due to the large number of equipment, this planning is hard and should take into account especially the most critical equipment needs. In the company under study, essentially three types ofmaintenance, preventive maintenance, corrective andautonomous maintenance are held.In the factory the main way of information registrationabout maintenance and failures is a software application thatsupports maintenance management.

In this software, allinterventions of preventive and corrective maintenancewhich are held in the company are registered. However, asconcerns autonomous maintenance, the record is onlymanual and the monitoring of the implementation of thistype of interventions is lacking.

Although there is no much reference to TPM within thecompany, it is noticeable that some of its pillars are implicitin its maintenance philosophy. However, it cannot beconsidered that TPM is successfully and entirelyimplemented.The autonomous maintenance is one of the pillars that isimplemented in the company. However, not all stages ofimplementation of autonomous maintenance wereperformed or successfully completed.

The project took place in some selected lines to moveforward with the pilot project. The lines chosen for the pilotproject were two line of the edge band area, one line of thefoil area, two lines of the cutting area.The choice of two lines of the edge band area is due tothe fact that in these lines many damages and unscheduleddowntimes are happened due to lack of cleanliness.

Inaddition, a large amount of dirt is accumulated at the end ofthe third shift, since maintenance only takes place after threeshifts. For these lines, the time and the number of operatorsrequired for performing autonomous maintenance taskswere not set, the standards were outdated with respect to thereal needs, and there was a discrepancy of tasks performedby different work teams.

An analysis of collected data hasalso shown that only about 55 percent of autonomousmaintenance tasks planned was actually performed in a line and about 24 percent in the other line, being only carried out dailytasks, weekly or monthly tasks were not performed.

The line of the foil area in its turn is considered one of themost problematic lines of business where it is oftennecessary forced stoppage to perform cleaning. In this line,there was no schedule or set time to perform maintenance,not even an adequate number of operators to performmaintenance.

The analysis of the records of maintenance hasshown that only 61 percent of planned maintenance tasks wereperformed. In addition, there was also a significantdifference in the tasks carried out by different teams.The first line of the cutting area, despite being a lineconsidered new in the company, is already very degradeddue to lack of cleaning and maintenance. In this line,autonomous maintenance is often not performed, registeringonly about six percent of planned tasks performed, and no standardsare available to facilitate its implementation.

Finally, in the second line of the cutting area, therealisation of first level maintenance is also not frequent andstandards are similarly not available.The selection of these lines has enabled a comprehensiveproject, testing the impact of autonomous maintenance inlines with different state of maintenance development.

Autonomous Maintenance

The first line of the edge band area showed a percentageof performed first level maintenance tasks of approximately 79 percent compared to 55 percent previously registered. In this sense, there is a very positive increase in carrying out first levelmaintenance tasks.

Concerning the realisation of tasks ofdifferent frequencies, significant improvements werenoticed since previously weekly and monthly tasks were notperformed. As regards the implementation of first levelmaintenance tasks for each team there is now uniformity.The second line of the edge band area also showedsignificant improvements in performing first levelmaintenance tasks.

The implementation of the pilot projectin this line led to a transition of about 24 percent of tasksperformed for about 67 percent at the end of the review period. Inthe second line of the edge band area, improvements werealso noticeable in the realization of weekly and monthlymaintenance, since these were not performed previously.

The realisation of tasks by the two teams operating in thesecond line of the edge band area was initially very similar,and at the end of the pilot project it remains also verysimilar thus fulfilling one of the main desirable goals.

Analysing the values concerning the completion of firstlevel maintenance tasks, in the line of the foil area about 73 percent were held at the end of the pilot project. Thissum is higher than the previous value of about 61 percent of theperformed tasks. The number of tasks performed was alsouniformly distributed among the three teams.

The first lineof the cutting area was the one with more interesting resultsfrom the standpoint of first level maintenance, once themethodology of first level maintenance was defined in full.In this sense, the percentage of tasks performed increasedfrom about six percent to 70 percent.

Finally, analysing the pilot project implementation resultsin the second line of the cutting area, where previously therewere no records, it appears that about 73 percent of firstlevel maintenance tasks were completed. Regarding thedistribution of tasks between teams, it appears that theworkload is balanced.

Analysis Of Stoppages

In order to examine the improvements that the pilotproject provided, it is important to make a comparison of thestoppages of the lines between the beginning and the end ofthe pilot project.Therefore, making an initial analysis of the stoppages of thefirst line of the edge band area, there is an overall reductionin every line stoppages, with the exception of stoppages forfirst level maintenance realisation, which means that tasksstarted to be carried out more frequently.

Therefore, it appearsthat the increase in time spent for performing first levelmaintenance positively influence all other stoppages,compensating the line stoppages and preventing damage ofthe equipment.In the second line of the edge band area, there has been adecrease of the main stoppages except stoppages for setup.

In the line of the foil area, generally there is also adecrease of stoppages related to failures of specificequipment. At the same time, there is an increase in thenumber of hours spent on first level maintenance, whichshows that the realisation of first level maintenance taskshas an influence in reducing stoppages due to equipmentdamage.

The training given to operators encouraged them toperform first level maintenance tasks and rose motivation.All trainings made, theoretical and practical training, ortraining in the new standards, allowed the employeesbecoming capable of performing the tasks efficiently.

It canbe said that the employees received all the necessaryinformation to become autonomous in the realisation andperception of all aspects related to first level maintenance.At the same time that these trainings allowed an evolutionin competency of each individual operator, also allowed abetter unity of the group and sense of responsibility for theimplementation of improvements in the areas.

All trainings enabled operators to perceive the importanceof the aspects related to the first level maintenance and alsothe implications and improvements that carrying out thesetasks can influence other improvements in their areas.

In short, these trainings contributed to increase versatilityof operators and to motivate them to carry out first levelmaintenance.In order to understand how employees feel about the pilotproject a questionnaire was carried out with a series ofquestions or statements to which operators answeredwhether they agreed or not, and could still give theiropinions and suggestions for improvement.

Thequestionnaire analysis allowed perceiving that the newinstructions were in accordance with the needs and thestipulated time was adequate in the view point of theoperators.The most added value of the questionnaire was theopinion of operators about some improvements that couldbe made in equipment to facilitate first level maintenanceand even to increase equipment yield.

Later, some of these suggestions have been analysed andsome of them were implemented not with considerablecosts, and other, those requiring more costs, had to beexamined more closely by the maintainer.In general, it can be concluded that in view of operatorsthe pilot project brought improvements in the realization of the first level maintenance, therefore fulfilling some of theexpected goals.