Maintenance strategy selection with pythagorean fuzzy AHP and pythagorean fuzzy WASPAS methods: A case study in a newspaper printing plant.

Businesses seek to gain a competitive advantage by lowering their production costs through optimizing their production operations. Studies show that the resources allocated to maintenance operations make up a large portion of production costs and that a third of the allocated resources is wasted as a result of improper decision-making and practices. When the advancements in technology, the increasing awareness regarding occupational health and safety and expectations such as quality products being produced at a high volume are considered, a proper maintenance strategy presents itself as a critical decision-making issue. The goal of this study is to choose the best maintenance strategy for a newspaper printing plant. Maintenance strategy selection is a fuzzy process that does not allow absolute judgments and one that consists of multi-criteria. Because of this, the study utilizes Pythagorean Fuzzy AHP to calculate the weight of the criteria and Pythagorean Fuzzy WASPAS to evaluate alternatives based on the criteria. For this study, the established criteria are safety, cost, feasibility and added-value as the main criteria with fourteen sub-criteria along with five potential alternatives for a maintenance strategy which are reactive maintenance, periodic maintenance, condition-based maintenance, predictive maintenance and reliability-centered maintenance. For evaluation, based on the structure of the criteria, decision-making groups were established that consist of maintenance, production, accounting and quality assurance departments. Based on the results of this study, it was determined that the best maintenance strategy for a newspaper printing plant is periodic maintenance. From the alternatives, predictive maintenance came at a close second while condition-based, reliability-centered and reactive approaches were third, fourth and fifth respectively. A sensitivity analysis with multiple parameters was conducted in order to test the validity of the study results and it was observed that, based on the results from the scenarios tested, that the level of validity is high. Keywords: Maintenance Strategy Selection, Multi-Criteria Decision Making, Newspaper Printing Plant, Pythagorean Fuzzy AHP, Pythagorean Fuzzy WASPAS