Statistical Quality Control and Process Capability Analysis for Variability Reduction of the Tomato Paste Filling Process

摘要

In this research some techniques for process statistical control were applied, such as frequency histograms, Paretodiagrams, process capability analysis and control charts. The purpose of this investigation was to reduce the variabilityof the canned tomato paste flling process coming from a tomato processing food industry that has problems with the netweight of their processed product. The results of the process capability analysis showed that 35.52% of the observationswere out of the specifcations during the months in study, which generates a real capability of the process (Cpk) of 0.124,and it indicates that the process does not have enough ability to fulfll the required specifcations by the frm. The processpotential capability (Cp) is 0.676. Given that Cpk < Cp, then it is concluded that the process is not centered, indicatingthat the measurement of the flling process is away from the center of the specifcations. The process fts 0.371 sigmabetween the process mean and the nearest specifcation limit. It was estimated that 40.42% of the cans produced duringFebruary did not meet the specifcations required, and neither did a 16.84% during March. In consequence of this, it wasnecessary to identify the potential causes of the can excess fllings. Afterwards, it was proposed an orthogonal array L9to adequate the process to the company flling specifcations. The optimum operating conditions achieved a 5.28 sigmaprocess quality. In addition, it was noted that the process had only 77.49 parts per million (ppm) out of specifcation. Thissituation places the tomato paste flling process as a world class quality process.