What is the problem?
The problem we are facing is the problem of weight variation regarding a specific product. In manufacturing, quality is defined as conformance to specification. However, variation always exists and there is never products that conform exactly to all the production capacity. Usually inspection is done in mass-production facilities to ensure conforming to specifications. Samples of each lot are inspected to ensure conforming to design specifications. SPC uses statistical tools to observe the performance of the production process in order to detect significant variations before they result in the production of a sub-standard article. Any source of variation at any point of time in a process will fall into one of two classes.
1) "Common Causes" – also called non-assignable or normal sources of variation. It refers to a wide range of sources that are present and make a repeatable distribution as time passes.
2) "Special Causes" – also called assignable sources of variation. They are unpredictable sources of variation and has an effect on only some of the process output.
Nearly all of the production processes have variations; most of them are minor and may be ignored. But the major ones should be reduced or eliminated to improve the process. Once the dominant causes are identified, they can easily be treated or removed, so we can call it a stable process. When a process is stable, its variation should remain within a known set of limits. That is, at least, until another assignable source of variation occurs.

Report description: * This report discusses the quality problem of a chosen product which is Granulated Sugar made by Euro Shopper Company. The problem was product variation which was spotted after the measurement of randomly purchased sugar packs. The team worked on studying the problem, understanding it and knowing its causes. In addition to, using some of the quality tools such as Gauge R&R, Statistical process Control and Process Capability calculations in order to solve or eliminate the cause of the problem. The problem in this case was the weight variation of the product.

* Gauge R&R is a method was used to verify the accuracy of the used measurement system. The product used in the Gauge R&R measurement was ice cubes. The group purchased 10 boxes of ice cubes of the same type and weight and started performing the measurements for the ten ice boxes and recording each measurement.

* Statistical process control charts were used to determine the variation problems using x chart and r chart.

Product description: * The product used for the live measurement of this assignment is Granulated Sugar manufactured by the Euro Shopper Company. Each pack of granulated sugar should be 500 grams according to the written information on the pack. However, after performing the measurements, the weight of the packs varied.

Figure 1: Euro Shopper Granulated Sugar

* The product used for the Gauge R&R measurements was Ice Cubes of 500 grams per pack.

Figure 2: Buzlat Ice Cubes

Project Aim:

* The aim of this project is to solve the weight variation problem of the Granulated Sugar packs by made by Euro Shopper Company, through a number of steps. These steps will help determine the cause of variation, then finding a way to reduce or eliminate the variation. Therefore, the process can be improved.

* Another aim of this project is to know how to choose the right measurement system for the assigned topic, and how to ensure the ability of the selected measurement systems to give accurate and precise results to be used in the live measurements.

Project Objectives:

* Selecting the proper measuring system. * Performing Gauge R&R on this measurement system to ensure its ability to give accurate and precise results using ice cube packs. * Performing live measurement of the granulated sugar packs to detect product variation. * The Statistical Process Control was used to visualize the collected data. * Improve the process by knowing the cause of variation and suggest ways of reducing or eliminating it.

Measurement System Selection:

The measurement system used is an electronic scale suitable for measuring solids or liquids. It was accessed at the School of Engineering on campus, it was suitable for our measurement because it was a sensitive measurement system of 2 digits accuracy. This scale was used after performing Gauge R&R on it, to ensure the scale’s accuracy.

Figure 3: Selected Scale

Gauge R&R: * A different product was used during the phase of validating the measurement system. * The team bought 10 packs of ice cubes which had a similar weight of the granulated sugar packs which was 500 grams per pack. * A beaker was used in order to measure the ice cubes accurately and without any losses. * The ice packs were numbered, in order to be measured by each operator in sequence. Then, the ten packages were measured randomly by each operator as shown in the figure below. * The data was recorded in the following table, where measurement 1 is the sequenced measurement, and measurement 2 is the random measurement.

| Claudio | Youssef | Sample | Measurement 1 | Measurement 2 | Measurement 1 | Measurement 2 | 1 | 510.5 | 510.5 | 510.5 | 510.5 | 2 | 591.6 | 591.4 | 591.6 | 591.5 | 3 | 591.2 | 591.2 | 591.2 | 591 | 4 | 517.8 | 517.7 | 517.5 | 517.5 | 5 | 489 | 489.2 | 489.1 | 488.9 | 6 | 491.5 | 491.5 | 491.7 | 491.5 | 7 | 490.4 | 490.4 | 490.4 | 490.4 | 8 | 492.3 | 492.1 | 492.1 | 492.3 | 9 | 490.9 | 490.9 | 490.9 | 490.7 | 10 | 492.7 | 492.7 | 492.7 | 492.5 |

The recorded data was used to perform Gauge R&R to ensure the accuracy and precision of the measurement system.

Figure 4: Gauge R&R measurements

Figure 5: Gauge R&R measurements

* Gauge R&R has three cases:

1. If the R&R% Cpk
So
The process is out of control so it has to be improved.

Cause of variation can be as a result of many reasons. In this case the cause can be due to bad packaging of the machine which allows grains of sugar to fall of the pack. It can also be as a result of bad transportation of the sugar packs which cause the loss of the weight.
Some packs were also over weighted, which is a problem that is caused by the machine or the operator.

Process Improvement and Control:

Actions should be taken to reduce the problem of variation, these actions can include:

* Maintenance of the packaging machine which can cause the loss of sugar granules if the product is not well packaged or not well closed. * Maintenance of the filling machine which can cause over-filling or less filled packs of sugar. * Training of workers and operators on how to avoid weight variation and how to detect it. * Making sure that the transportations of the product happens without damaging the sugar packs to avoid weight loss.

Conclusion: * Gauge R&R is a necessary tool for choosing and validating a measurement system. * Product variation should be measured and translated into SPC tools like control charts in order to reduce it or eliminate it. * Process Capability helps us to determine the nature of the process and whether it is in or out of control. * Actions should be taken in order to reduce or eliminate the special or common causes of variation.