What should be done when the bourdon tube experiences increased pressure?

When the bourdon tube experiences increased pressure, it tends to straighten. This phenomenon occurs due to the characteristics of the bourdon tube design, which consists of a coiled shape. When pressure is applied internally, the force causes the tube to try to expand, which results in a straightening effect.

This response to pressure is a fundamental principle of how bourdon tubes operate in pressure measurement devices. The internal pressure forces a change in the shape of the tube, and as it straightens out, this motion is typically transmitted through a mechanical linkage to a needle on a gauge, indicating the level of pressure.

In contrast to the other options, a bourdon tube does not become flat or bend more under increased pressure, and while it could theoretically break under extreme pressure beyond its design limits, this is not a characteristic action of the tube in normal operating conditions. The tendency to straighten under pressure is essential for the functionality of pressure measurement systems using bourdon tubes.