What type of thrust control is best on vertical bends?

• A. Thrust anchors
• B. Expansion joints
• C. Anchored pipes
• D. Flexible couplings

Answer: (A)

Vertical bends create axial thrust as flow changes direction, so the system must resist that push or pull at the bend. Thrust anchors are designed specifically to lock the pipe in place and take up the axial forces generated by changes in direction or by valve closures and thermal expansion. They prevent movement, protecting joints and supports from the full thrust load.

Expansion joints, while useful for absorbing movement due to temperature changes, are meant to accommodate displacement rather than stop thrust from developing. Relying on them to restrain thrust at a vertical bend can allow motion, stress, and potential leaks. Flexible couplings provide some flexibility to handle minor misalignment and vibration, but they’re not built to resist strong axial thrust and thus don’t offer reliable thrust control at bends. Generic anchored piping lacks the targeted restraint that a proper thrust anchor provides, especially at a critical change in direction.

So, the best way to control thrust at vertical bends is to use thrust anchors to restrain the axial forces and keep the bend stable under operating and transient conditions.