Recirculating
Shot Peening Method
Recirculating Shot Peening Method
(Former name: Eco-clean Hybrid method)
About
What is circular shot Peening method?
This is an epoch-making method that enables "shot peening", a technology that improves the fatigue strength of steel products by simply adding 1 step when repainting a steel bridge.The basis of this is the circular blast method, which is a blast method that reduces environmental impact.
Recirculating Blasting Method®
Shot peening treatment
Award history
- Japan Society of Civil Engineering Chubu Branch Technical Award (2019)
- Ministry of Education, Culture, Sports, Science and Technology Award (2022)
- Ministry of Land, Infrastructure, Transport and Tourism NETIS registered CB-180024-VE Utilization Promotion Technology
- Japanese Patent No. 6304901/No. 6501718
- JIS G 0951 (Shot for circular shot peening to steel structures)
- US Patent US 11959148 B2
- Korean Patent 10-2025-0019722
Features
*Excerpt from "Effect of Shot Peening on Fatigue Strength of Welded Joints"
(Japan Society of Civil Engineering, Heisei 28 National Conference Paper Presentation Excellent Speaker Award)
By hitting countless special steel balls (peening materials) on the steel surface at high speed and plastic deformation only near the surface, it is possible to give compressive residual stress to the surface layer.This technology improves resistance to fatigue cracks and stress corrosion cracking.In addition, the crystal on the surface is miniaturized to suppress the growth of cracks.
Improved durability
Added compressive residual stress
Improved fatigue durability
Miniaturization
Miniaturization of crystals
Reduce crack growth
Curing
Surface hardening
New cracks become harder to enter
"Recirculating Shot Peening Method" that makes impossible possible
Flow
Erection of Scaffolding and Protective Equipment
Protective equipment is installed around scaffolding to prevent the scattering of abrasive material and dust. Also used effectively with shot peening.
Base adjustment degree 1 type
Due to specific dust-generating work, workers perform the task equipped with airline respiratory gear.
Inspection of welds, etc.
Check for cracks.Repair of the occurrence was examined and shot peening was carried out in the non-occurrence part.
Peening treatment
Due to the injection by compressed air, work efficiency is good and construction in narrow areas is also possible.Proficiency is also unnecessary.
Form management
We have established a management method using a dedicated mold measuring device (coverage checker) to ensure stable quality.
Secondary Blasting (Finishing Blasting)
Apply anticorrosive primer within 4 hours after quality confirmation.
Painting
Primer, intermediate coat, top coat
Completed
Shot peening works on existing steel bridges
As of the end of 2025/1