cmd.CommandText = "proc_report1";
                    cmd.Parameters.AddWithValue("@rep_year", param.rep_year);
                    ....

                    DataTable dt_table = new DataTable();

                    SqlDataAdapter da = new SqlDataAdapter(cmd);
                    da.Fill(dt_table);


                    ReportDataSource rep_ds_table = new ReportDataSource("dsTable", (DataTable)dt_table);

                    ReportViewer1.LocalReport.ReportPath = "Reports\\ReportHDay1.rdlc";
                    
                    ReportViewer1.LocalReport.DataSources.Clear();
                    ReportViewer1.LocalReport.DataSources.Add(rep_ds_table);
                    
                    ReportViewer1.LocalReport.Refresh();

 ReportViewer1.LocalReport.ComponentByName("Chart1").ComponentByName("Series1").DataValue = "[sum(field1)]";

        objXmlDocument = new XmlDocument();

        objXmlDocument.Load("http://localhost:4550/Reports/Report2.rdlc");
        mgr = new XmlNamespaceManager(objXmlDocument.NameTable);

        string uri = "http://schemas.microsoft.com/sqlserver/reporting/2008/01/reportdefinition";

        mgr.AddNamespace("df", uri);

        // правка
        XmlNode n = objXmlDocument.SelectSingleNode(
                "/df:Report/df:Body/df:ReportItems/df:Chart[@Name='Chart1']/df:ChartTitles/df:ChartTitle[@Name='Default']/df:Caption"
                , mgr);
        if (n != null) n.InnerText = "ЗАГОЛОВОК ОТЧЕТА";
       
        // подсовывание отчета
        byte[] rdlBytes = Encoding.UTF8.GetBytes(objXmlDocument.OuterXml);
        MemoryStream stream = new MemoryStream(rdlBytes);
        ReportViewer1.LocalReport.ReportPath = string.Empty;
        ReportViewer1.LocalReport.LoadReportDefinition(stream);