sentences:  Several material strengths—termed "Grades" and ranging from to minimum yield strength—are available for most combinations of OD and wall thickness to meet various design needs.Finally, the API publications provide performance minimums for longitudinal strength ("joint strength") as well as resistance to internal (bursting) and external (collapsing) pressure differentials.A typical piece of casing might be described as 9-5/8" 53.5# P-110 LT&C Rg 3