The Use of Non-Destructive Methods in Technical Assessment of Agricultural Machinery Under Field Conditions

摘要

Agricultural machinery and equipment operate in extremely harsh conditions. Excess dust and operation under variable environmental conditions result in increased wear of the machinery mating parts. Some machines are used only for a limited period of time during the year. For the rest of the year the machines are often stored in severe climate conditions (high humidity and variable temperatures). Malfunctions of agricultural machinery during operation can result in a significant loss for the farms. The authors of this study attempted to ascertain whether the non-destructive inspection methods allow an early detection of possible defects in the areas under observation. The research was carried out on different components of the agricultural machinery, the example of which is the shaft of a crusher (prone to cracking in the rear seat of the rolling bearings), welded joints, high-pressure tubing and metal plumbing fixtures. The study used a Krautkramer USM 35 XS ultrasonic flaw detector with a set of ultrasonic transducers operating on different frequencies (2 to 20MHz). The study was conducted in the NDT laboratory of Poznan University of Technology, the Masz-Rol manufacturing plant and several farms. The investigations have shown that the ultrasonic method allows a detection of fatigue cracks of the crusher shaft, thus enabling an early replacement. The authors have also confirmed the erosion wear, the ability to inspect high-pressure pipe fixtures and various connections such as the welded joints or spot welded bonds. The authors claim that at the production stage of agricultural machinery it is necessary to write instructions as to how to conduct ultrasonic inspections of components prone to malfunctions. These instructions should then be attached to the machine documentation. This would allow a timely detection of latent defects that may contribute to the costly downtime of the machinery or accidents during operation. Due to the design of agricultural machinery, the authors have conducted most of the research using their proprietary procedures.