You have to perform the following steps:
1. Make an Output Relate (using the Operations Tab of the H2OMAP SWMM Browser) which will be the same as the Pipe Summary Table in the Output Report Manager
2. Run the model to make the Output Relate and then update the Relate (Figure 1)
3. Using Windows Explorer navigate to the HSDB folder of your H2MAP SWMM project
4. Continue to the Relate Subfolder and open up the Relate DBD file in Excel (Figure 2)
5. You cannot SAVE this file but you can save is as a new Excel File
Figure 1. Output Relate in H2OMAP SWMM to use the Pipe Summary Table
Figure 2. How to Use the Output Relate in Excel