Which statement about rotating mechanical seals is false?

The statement regarding the mating ring turning with the shaft is false because, in a rotating mechanical seal, the sealing ring (also known as the primary ring) is the component that rotates with the shaft, while the mating ring (or secondary ring) is stationary.

The design of mechanical seals typically involves a rotating sealing ring, which creates a seal against a corresponding stationary ring. The stationary ring is generally held in place, not turning with the shaft. This arrangement allows for effective sealing while accommodating shaft movement.

Understanding the roles of the sealing and mating rings is crucial for the proper operation of mechanical seals. The sealing ring's rotation allows it to maintain contact with the stationary mating ring, preventing the leakage of fluids. Meanwhile, the spring that provides the necessary force on the sealing surfaces is also typically attached to the stationary components, not the rotating assembly. Thus, the mechanics of rotation and stationary positions in the design illustrate why the statement about the mating ring turning with the shaft is incorrect.