African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6786

Full Length Research Paper

Construction of control charts in production process of soybean oils

Suzana Leitão Russo*, Tanara Elisa Kreibich, Maria Emilia Camargo, Gabriel Francisco da Silva and Simone de Cássia Silva      
Department of Statistics, Federal University of Sergipe-Av Marechal Rondom s/n, Bairro Roza Elze, CEP 49000-000 São Cristóvão, SE. Brazil.  
Email: [email protected]

  •  Accepted: 22 June 2012
  •  Published: 07 August 2012


When dealing with a production line, we usually think that all products are exactly alike, but if you look a little more closely, we will realize that they are not as equal as well, and if these differences are large, it will be easily noticed. The whole process, however well designed and controlled as it is, has a variability component that cannot be eliminated. It is the natural variability of the process, which is the result of a series of small perturbations (random causes) against which virtually nothing can be done. However, disturbances may occur more (special causes), which has the effect of moving the distribution of the random variable X and/or enhance their dispersion. In this study, the aim was to apply the techniques of statistical quality control, constructing the control charts in order to verify whether or not the process is under control. The techniques of control charts were applied to the variables of the process of production of soybean oil at one Industry, where one hundred samples were collected, with the following variables: acidity of oil soybean, protein and humidity content of soybean meal.


Key words: Soybean, statistical process control,  control charts.