Reliability Analysis of Combine Harvesters

Öz

The estimation of required total operational width of combine harvesters beforehand, especially for relatively big farms, is so important in terms of both the timely and possible least cost operation. Determination of required total operational width is a little bit complicate due to the difficulties in estimation of lost time resulted from unplanned breakdowns.

In the context of this study, reliability analyses of 14 combine harvesters with same made and model were made based on the breakdown records which contain time between failures. The historical data of time between failures were modeled according to Weibull Distribution with three parameters. A developed software, namely WEPTIBFES v 2.0 was used in parameter estimation. Additionally, the module of Monte-Carlo simulation was added into software to simulate the time between failures.

As a result of the study, totally 2470 data from 14 combine harvesters for last 10 years were evaluated. The estimated time between failures were calculated for given sub-systems of combine harvester. Weibull distribution parameters, the estimation statistics of b that defines the shape of distribution were determined. Additionally, and the result of validation tests were performed according to Kolmogorov-Smirnov test procedure. The lowest and the highest estimated time between failure values for cutting bar/feeding mechanism and components of control system were 82.16 and 234.74 hours respectively, while actual values were 88.2 and 254.2 hours.

Anahtar Kelimeler

• Combine harvester,grain harvesting,reliability

Reliability Analysis of Combine Harvesters

Öz

 

ABSTRACT: The estimation of required total operational width of combine harvesters beforehand, especially for relatively big farms, is so important in terms of both the timely and possible least cost operation. Determination of required total operational width is a little bit complicate due to the difficulties in estimation of lost time resulted from unplanned breakdowns.

In the context of this study, reliability analyses of 14 combine harvesters with same made and model were made based on the breakdown records which contain time between failures. The historical data of time between failures were modeled according to Weibull Distribution with three parameters. A developed software, namely WEPTIBFES v 2.0 was used in parameter estimation. Additionally, the module of Monte-Carlo simulation was added into software to simulate the time between failures.

As a result of the study, totally 2470 data from 14 combine harvesters for last 10 years were evaluated. The estimated time between failures were calculated for given sub-systems of combine harvester. Weibull distribution parameters, the estimation statistics of b that defines the shape of distribution were determined. Additionally, and the result of validation tests were performed according to Kolmogorov-Smirnov test procedure. The lowest and the highest estimated time between failure values for cutting bar/feeding mechanism and components of control system were 82.16 and 234.74 hours respectively, while actual values were 88.2 and 254.2 hours.

Kaynakça

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