Almost certainly not. Standard SMPSs never have isolated outputs, which is what they would need to be. The outputs are already 'joined' at the zero (ground) and trying to join them in any other way would not be good!
I have an evaluation kit which has to be tested at 15 VDC, 8A to 60 VDC 2A and in between ranges. I need a power supply which can supply 8A/6A/4A at 15 /20/30 V DC ranges. I thought SMPS can deliver the current. So I am trying to get 17 VDc ( 12 + 5 ) by ganging.
Infact the input power can be greater than 120 watts.