Stress corrosion cracking is defined as the delayed failure of alloys by cracking when exposed to certain environments in the presence of static tensile stress. The importance of a conjoint action of corrosion and stress is reflected in the definition; an alternate application of stress and corrosive environment will not produce stress corrosion cracking. The stress level at which the failure occurs is well below the stress required for a mechanical failure in the absence of corrosion. The minimum stress below, which stress corrosion cracking occurs, is called the threshold stress.
Failures of structures often involve environmentally assisted cracking. Stress corrosion cracking (SCC) is one of the most common environmentally assisted failure modes encountered. It typically occurs due to improper materials selection or heat treatment, design issues, and unforeseen environmental conditions, such as inadequate maintenance, thermal transient conditions, or lack of consideration of residual stresses.
Stress joints are steel or titanium constructed. Its features include the following- integral tieback connector body or forged flange on bottom; and machined or welded riser connector on top. It can be built based on required specification that includes the joint length, wall thickness and tapered length.