English

Abstract

The use of tractors is indispensable and essential to the agriculture. However, despite being efficient machines, tractors may fail in their projects, leading to the appearance of vibrations in different parts of their structure. Many studies show that the daily exposure to high levels of vibration, these are a risk factor for the health of the whole human body. In view of that, the purpose of this study was to evaluate the vibration levels in two static tractors, with the following specifications: Tractor (1) without cab, 4×2 model TDA manufactured in 1997, 89 kW of nominal engine power; tractor (2) with cab 4×2 model TDA manufactured in 2014, 65 kW of nominal engine power. The rotations were determined by the manufacturer´s manual of both tractors. The vibrations were measured by the accelerometer, properly calibrated. Data were collected in the Test Center of Machines and Agroforestry tires - belonging to the Faculty of Agricultural Sciences, UNESP Botucatu - SP. The accelerometer was fixed at different points of the tractors, collecting their overall structural vibration. For the conditions that were conducted this study, it can be concluded that the tractor vibrations tend to increase according to the addition of the use of time of the tractors. The engine is a great source of vibration as noted in both tractors, as soon the vibration in steer wheel control system is a concern, due to the fact that is a place where the operator maintain constant contact, however the vibrations levels in tractor with cabin were lower than tractors without cabin.  The cabin is an important equipment in machines protecting the operator from the vibrations, besides the weather roughness, dust and possible objects that could be launched during the operations.    Key words: Vibration, ergonomics, working environment, operator. &nbsp