This paper describes the generation of procedures for the stages of operation and preventive maintenance of the machine with greater criticality of a production line of donuts. The generation and application of this procedure in the factory, seeks to reduce machine downtime and ensure increased operational reliability of this, because the current strategy is corrective maintenance to perform preventive maintenance activities are changed. In addition to this procedure aims to bring discipline to the operators to perform maintenance activities such as cleaning, inspection, lubrication and adjustment. To develop the project in the first place relevant information using questionnaires and conducting interviews with each machine operators on the line, obtaining information about the failures of each was collected. An analysis of criticality of the three machines that make the production line, achieving determined in this way what they needed further attention for its high criticality was performed. Subsequently the technical operation and maintenance procedures were developed, which together with proactive maintenance activities proposed seeks to reduce the number of machine downtime and increase the MTBF. Finally, a training plan is implemented operators in all areas of knowledge of the company, thereby leading to high levels of competence, good skills and strong technical knowledge to form.