var
pdf_name, fname : string;
fs:TFormatSettings;
begin
.......................
//I think there is a newer function that generates a random name for files
pdf_name:= 'Some_Name' + '_'+FormatDateTime('ddmmyyyynnss', Now(), fs)+'.pdf';
fname := UniServerModule.LocalCachePath + pdf_name;
with YourTable do
TBlobFile( FieldByName( 'The_Name_Of_The_Blob_Field' ) ).SaveToFile(fname);
UrlFrame.BeginUpdate;
UrlFrame.Url:=fname;
UrlFrame.EndUpdate;
end;
Pay attention to paths !