Dr. O'Donnell and Dr. Porowski were co-inventors of the Mechanical Stress Improvement Process (MSIP). In considering the stress corrosion cracking problem in the heat affected zone of field welds in BWR primary pumping, they developed a reliable mechanical stress improvement process which applies compressive stresses and is easy to control and verify. MSIP was developed with supporting finite element analysis and tests which show that it provides compressive stress fields in both the axial and circumferential directions at the inner surface of weldments. The Process was developed for pipe-to-pipe, pipe-to-discontinuity (such as valve body) and pipe-to-vessel nozzle configurations. MSIP has been performed at 40 nuclear power plants worldwide:
| Utility | Plant | Year | Pipe & Fittings | Nozzles & SE's | Total | Notes |
| CeCo | Dresden 3 | 1986 | 50 | 2 | 52 | |
| CeCo | LaSalle 2 | 1987 | 25 | 29 | 54 | |
| CeCo | Quad Cities 1 | 1987 | 36 | 2 | 38 | |
| CP&L | Brunswick 2 | 1988 | 0 | 15 | 15 | 1 |
| CeCo | Quad Cities 2 | 1988 | 43 | 4 | 47 | |
| Nuclenor | Santa Maria de Garona | 1988 | 24 | 0 | 24 | |
| OKG Aktiebolag | Oskarshamn | 1988 | 1 | 0 | 1 | 1 |
| CP&L | Brunswick 1 | 1988 | 0 | 10 | 10 | |
| CeCo | LaSalle 1 | 1988 | 15 | 15 | 30 | |
| CeCo | LaSalle 2 | 1988 | 8 | 0 | 8 | |
| CeCo | Dresden 2 | 1988 | 82 | 22 | 104 | |
| PeCo | Limerick 2 | 1989 | 2 | 16 | 18 | |
| Northeast | Millstone 1 | 1989 | 0 | 22 | 22 | |
| Detroit Edison | Fermi 2 | 1989 | 6 | 21 | 27 | |
| CeCo | Quad Cities 1 | 1989 | 28 | 12 | 40 | |
| CP&L | Brunswick 2 | 1989/1990 | 16 | 20 | 36 | 2 |
| CeCo | Quad Cities 2 | 1990 | 30 | 14 | 44 | 2 |
| Teollisouden Voima Oy | TVO | 1990 | 5 | 0 | 5 | |
| Niagara Mohawk | Nine Mile Pt 2 | 1990 | 0 | 1 | 1 | |
| Taiwan Power | Kuosheng 2 | 1990 | 2 | 0 | 2 | 1 |
| CP&L | Brunswick 1 | 1990/1991 | 10 | 24 | 34 | 2 |
| Northeast | Millstone 1 | 1991 | 34 | 9 | 43 | |
| Iberdrola | Cofrentes | 1991 | 0 | 42 | 42 | |
| Boston Edison | Pilgrim 1 | 1991 | 16 | 0 | 16 | 2 |
| PeCo | Peachbottom 3 | 1991 | 10 | 0 | 10 | |
| PeCo | Limerick 1 | 1992 | 0 | 7 | 7 | |
| Cleveland Elec. | Perry 1 | 1992 | 0 | 27 | 27 | 1 |
| TVA | Browns Ferry 3 | 1992 | 71 | 29 | 100 | 2 |
| GPU | Oyster Creek | 1992 | 70 | 0 | 70 | 2 |
| Georgia Power | Hatch 1 | 1993 | 18 | 11 | 29 | |
| TVA | Browns Ferry 2 | 1993 | 12 | 0 | 12 | 2 |
| PP&L | Susquehanna 2 | 1993 | 8 | 6 | 14 | |
| PeCo | Limerick 1 | 1994 | 4 | 14 | 18 | |
| Georgia Power | Hatch 2 | 1994 | 0 | 18 | 18 | |
| PP&L | Susquehanna 2 | 1994 | 7 | 5 | 12 | |
| GSU | River Bend | 1994 | 0 | 28 | 28 | |
| WPPS | WNP-2 | 1994 | 6 | 38 | 44 | |
| GPU | Oyster Creek | 1994 | 39 | 16 | 55 | |
| 678 | 479 | 1157 |
(1) Some weldments with pre-existing cracks
(2) Weldments for replacement piping made of SCC immune materials
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