Scatter graph content

The scatter graph is capable of showing both recut and measured crude data. Recut data is obtained by mathematically recutting the crude description with is used to store the assay data in Assay. Measured data is actual data recorded by the laboratory and entered into Assay during assay workup. This data is used to create the crude description, but is then not normally used to output property data.

For example during analysis a crude may be distilled to obtain a kerosene fraction which is recovered between 200 - 260°C. The density of this fraction is then measured and recorded as 0.7956 g/cc. This data is entered, along with all the other measurements during assay workup.

When the crude description is generated a density property profile is created using this kerosene density measurement, along with all of the other stream's densities, and the other crude properties entered. This density profile is represented by a smooth property profile curve.

If this density property profile is recut between 200 - 260°C then the density may be calculated to be 0.7989 g/cc. Normally when properties are output from Assay this recut value is returned as the density of the kerosene stream.

Occasionally it may be required that the actual original laboratory measurement (0.7956 g/cc) is returned as the density of the kerosene stream. In Assay this is referred to as the measured value and must be explicitly requested.

Icons on the graph toolbar are used to change whether measured or recut property values are displayed on the scatter graph:

• : View the generated values obtained by recutting the assay property profiles

• : View the measured values for the property obtained in the analytical laboratory

It is also possible to switch between measured value and generated value modes using the context menu of the property profile graph.

When the displayed data is changed from recut data to measured data the progress indicator is displayed as the original assays are checked to see if they have any matching measurements. The progress indicator automatically closes when the assays have been checked and the matching data is displayed on the graph.