Issue:
Customer has experienced significant roll body diameter loss and thermal fatigue cracking of continuous caster rolls. This has resulted in reduced campaign life below the goal tonnage because of open gap conditions. Additionally, the severe cracking has reduced the number of allowable skin cuts before full roll repair is required.
Solution:
SMS group has introduced the advanced roll overlay RollGuard™ CS-10. The CS-10 resulted in a 30%-50% reduction in diameter loss compared to the previous overlay. This overlay also reduced thermal fatigue cracking severity, which reduced the required skin cut stock removal by 40%. The success of the advanced roll overlay allowed the customer to not only meet their tonnage goals but increase them. The results also allowed for additional skin cuts between full roll repairs, which further reduced maintenance costs.
Chemical Composition Comparison
| Standard Overlay | CS-10 Overlay | |
| C | .12 | .14 |
| Cr | 12.5 | 12.8 |
| Ni | 2.5 | 2 |
| Mo | 1.3 | 1.3 |
| Residuals | Nb, V | Nb, Ti, N |