Water Jet Peening developed by our partner-Hitachi


Modifies residual stress state from tensile to compressive


The industry has recognized that some of the materials used in both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs) are susceptible to stress corrosion cracking caused by environmental conditions.

Our solutions address this concern by reducing residual tensile stress near metal surfaces and are effective in mitigating Intergranular Stress Corrosion Cracking (IGSCC) and fatigue failure.   

IGSCC can occur when a harsh environment is combined with stress and susceptible material. Removing any of these factors, can stop the conditions that can promote IGSCC.

The industry considers peening (Laser and/or Water Jet) as an effective option for removing the conditions for IGSCC. This surface treatment technology changes the metal surface from a tensile stress condition to a compressive stress condition. 

Water Jet Peening & Laser Peening

Water Jet Peening (WJP) and Laser Peening (LP) are surface mitigation approaches that protect plant assets, reduce operating costs, and can potentially offer inspection relief for certain plant equipment. WJP was developed by our partner, Hitachi, and LP was developed by MIC, a Curtiss Wright company.

WJP and LP employ established Surface Stress Improvement (SSI) technology by modifying the residual stress state from tensile to compressive, thereby mitigating primary water stress corrosion and cracking. Both technologies are recognized by EPRI as proven surface mitigation techniques.

WJP has been successfully applied in 23 of 24 Japanese PWRs and 18 BWRs in Japan since 1999. In addition, WJP is being applied to new ABWR units during fabrication and construction. The Laser Peening process is well established in applications for aerospace and power industry components since 2002, and is readily adaptable for nuclear power plant applications.


Water Jet Peening

  • Established Surface Stress Improvement (SSI) technology, successfully used in Japanese BWRs and PWRs since 1999
  • Developed by Hitachi
  • Authorized by JSME (Japan Society of Mechanical Engineers)


Laser Peening

  • Well-established in applications such as steam turbines and aviation equipment since 2002 
  • Developed by Curtiss Wright Surface Technologies.


Water Jet Peening Benefits

  • Robust and flexible parameters
  • Non-complicated system/equipment
  • Developed by GEH’s global nuclear partner, Hitachi
  • Certified as residual stress improvement method by Japan Power Engineering and Inspection Corporation (JAPEIC).
  • Does not introduce any foreign materials
  • Maneuverable through congestive environments and restrictive spaces with ease
  • No adverse effect on UT inspectability after application
  • Reduced application time and widened application range 


Laser Peening Benefits

  • Highly precise, spot by spot placement
  • Transportable laser peening system and beam delivery technology can operate inside reactor containment building
  • Developed by MIC, a Curtiss Wright company and recognized as an acceptable peening method by EPRI.
  • Does not introduce any foreign materials
  • No adverse effect on UT inspectability after application
  • Offers the deepest compressive stress layer of any technology being offered