Inspection of Rubber Parts of Milking Equipment by Non-Destructive Testing Method

Abstract

The presented study deals with determining the wear of the inner surface of teat cup liners during exploitation based on roughness. The course of wear of the teat cup liner was assessed by an innovative non-destructive method. For this purpose, a measuring stool was made, by which it is possible to measure roughness without disassembling the teat cup liner from the teat cup shell. The wear of the liners was monitored using a roughness meter at randomly selected six stands in a herringbone parlour. In the first measurement in the winter period, the teat cup liners that had been stored on the farm for three years were used. In the second summer measurement, the liners were purchased before their use. When comparing the Ra and Rz parameters from the first and second measurements in both cases, there are statistically significant differences in the measured values in favour of the second measurement (P = 0.000 <0.05). The average roughness values Ra, Rz in the first measurement were 0.721 μm and 3.282 μm and in the second measurement 0.484 μm and 2.43 μm. There is a zero degree of connection between the roughness of the teat cup liners and the time of use, i.e. there is very little or no correlation. From our observations, it follows that the deteriorated quality parameters of the roughness of the liners in the first measurement were caused by using inappropriately stored liners. The new method for checking the condition of liners has proven itself in practice. The method is fast, less laborious, and results are available in a shorter time for further evaluation and drawing conclusions for the company manager.

Keywords

• teat cup liner
• roughness
• exchange period of rubber parts