Changes in contour or discontinuities in structure that cause local increases in stress.

The algebraic ratio of two specified stress values in a stress cycle. Two commonly used stress ratios are: (1) the ratio of the alternating stress amplitude to the mean stress. A = Sa/Sm and (2) the ratio of the minimum stress to the maximum stress. R =Sm ...

Heat treatment carried out in steel to reduce internal stresses.

A cracking process that requires the simultaneous action of a corrodent and sustained tensile stress. This excludes corrosion-reduced sections that fail by fast fracture. It also excludes intercrystalline or transcrystalline corrosion, which can disintegr ...

A scaling factor, usually denoted by the symbol K, used in linear-elastic fracture mechanics to describe the intensification of applied stress at the tip of a crack of known size and shape. At the onset of rapid crack propagation in any structure containi ...

In fatigue, the variation in the stress-intensity factor in cycle, that is, Kmax-Kmin.

Also called postweld heat treatment cracking, stress-relief cracking occurs when susceptible alloys are suhjected to thermal stress relief after welding to reduce residual stresses and improve toughness. Stress-relief cracking occurs only in metals that c ...

Old sailing ship term for taking a nap.

A fatigue fracture feature, often observed in electron micrographs, that indicates the position of the crack front after each succeeding cycle of stress. The distance between striations indicates the advance of the crack front across that crystal during o ...

On a square-rigged ship, the act of lowering a spar or yard to the deck.

A longitudinal stiffener for the side of a ship, made of angle bar, bulb angle channel or plates, etc. Depending upon their locations, stringers are known as bilge stringers, side stringers, hole stringers, etc.

Removing cargo from a container (devanning).

The difference between the maximum extended height and the compressed height of an air actuator.

That part of the total stroke which can be utilized repeatedly in actuator applications. It is measured starting at the compressed height and is the difference between the compressed height and the actuator height limit.

Wind with a speed between 22 and 27 knots (25 and 31 mph); Beaufort scale number 6.

Wind with a speed between 41 and 47 knots (47 and 54 mph); Beaufort scale number 9.

A light spar set fore and aft on a boat, serving as a spread for the boat cover.

Metal fitting attached to the hull that supports and aligns the aft portion of the propeller shaft.

A popular term used for a length of wood or steel used in or for wall framing.

Extending a sail using a whisker pole