da/dN = 10^(-10) * (50 MPa√m)^2.5 = 2.5 * 10^(-5) inches/cycle
where σ is the applied stress, a is the crack length, and π is a constant.
where da/dN is the crack growth rate, C and m are material constants, and ΔK is the stress intensity factor range.
K = σ√(πa)
The team also discovered that the pipeline had been subjected to a series of pressure cycles, with pressures ranging from 500 to 900 psi. These cycles had caused fatigue cracks to form and grow in the weld region.