Bending Strength Ratio BSR In Drilling String BHA
Bending Strength Ratio Definition

In General, Bending Strength ratio BSR is a ratio of the relative stiffness of the box to the pin for a given connection. The predominant consideration, especially in selecting larger Bottom Hole Assembly BHA connections is (BSR).  In Drill String Design If we select a connection with either a pin or box that is out of balance with the other member, we tend to increase the stress level and accelerate fatigue in the weaker member.
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