Question about BRepOffsetAPI_MakePipeShell . Is it can make the path wire is in the center of the profile

I am use BRepOffsetAPI_MakePipeShell to sweep.

The white ones are what I sweeped.The red line is input path wire.

I find the red line is not in the middle of the bottom of the result.How can i do

Much Thaks!

BRepOffsetAPI_MakePipeShell pipeMaker2(pathWire);
    pipeMaker2.Add(aTransdWire, Standard_True, Standard_True);
    pipeMaker2.SetMode(Standard_True);
    pipeMaker2.SetTransitionMode(BRepBuilderAPI_RightCorner);
    pipeMaker2.Build();