The 2012 Edition of B31.3 placed an upper limit on Sc and Sh used in the expansion stress range allowable stress. These values cannot exceed 138 MPa (20ksi).
Sc and Sh are typically based on a fraction of yield or tensile strength. Since higher strength steels have not shown a similar increase in fatigue strength, the Code's fatigue check removes that overage.
Maximum expansion stress range using (1a), then, is 1.5(138)= 207 MPa