The ChartSheetCollection object stores all chart sheets in the specified workbook. Use the IWorkbook.ChartSheets property to access this object. The ChartSheetCollection.Item property enables you to get an individual chart sheet by its name or index in the collection.
To create a new chart sheet, use the ChartSheetCollection.Add or ChartSheetCollection.Insert method. To move an existing chart to a chart sheet, use the chart's ChartObject.MoveToNewChartSheet method.