PREDICTABILITY IN THE PRODUCTIVE PROCESS OF THINNING AND CLEARCUTTING MECHANIZED OPERATIONS IN Pinus taeda L.

Abstract

Some organizations in the Brazilian forestry sector, especially in the activities carried out in forest stands, do not follow the development pace of other industries and the adoption rate of management and quality methodologies and tools. This study aimed to evaluate the predictability of timber harvesting process based on critical points identified in the selective thinning and clear cut operations. Interviews and Pareto chart were used, for the identification and evaluation of the critical points, respectively, and for the evaluation of the process, it was used the Statistical Process Control (SPC) by attributes and variables in the main failures. In the interviews conducted with workers, seven critical points were identified. The evaluation with Pareto chart showed that 80% of the failures identified during harvest are attributed to the damage to the remaining trees, sorting (measures of length and diameter of the product) and stump height. Among the possible causes of the critical points are problems with employees’ training, regular maintenance of machinery and operations planning. In the evaluation with the CEP, the control charts indicated that the sorting and stump height, although within the limits specified by the company, was considered unstable and unpredictable

Quality Function Deployment (Qfd) Applied to the Variables That Influence Quality Costs in Mechanized Forest Harvest Operations

“…This study sought to continue the work carried out in 2016 and later published by Garcia et al (2020), who identified the critical success factors that occur in harvesting operations through three stages: process mapping, identifying and evaluating critical points, and process evaluation. Subsequently, the methodology described by Jacovine et al (1999) was adopted, aiming to determine the variables that influence quality costs in the following categories: prevention, evaluation, and internal and external flaws.…”

“…The elaboration of the quality house sought to evaluate the demands of the customers in order to reduce costs and improve the relationship with external customers (wood processing industry, represented in this research by the company's commercial department) and internal customers (forestry sector, responsible for preparing the area for a new cycle). This set configures the "desired quality", based on the critical success factors pointed out by Garcia et al (2020) (assortments, stump height, trees left in the area) for the two interventions evaluated and damage to the remaining trees in the fourth thinning. Later, customer demands were split into variables that influence quality costs (technical characteristics).…”

“…Variables that influence the quality costs Relative weight of the process % Therefore, the critical factors raised by Garcia et al (2020) were: assortments, stump height, trees left in the area for the two interventions evaluated, and damage to the remaining trees in the fourth thinning. The "pretracing" for both interventions was added by the responsible team (Table 2).…”