Destructive Testing:

Destructive testing is undertaken in order to understand a specimen’s performance or material behaviour, these procedures are carried out to the test specimen’s failure. Destructive testing procedures can either follow specific standards or can be tailored to reproduce set service conditions.

 

Non Destructive Testing:

Non-destructive testing (NDT) is a testing and analysis technique used by industry to evaluate the properties of a material, component, structure or system for characteristic differences or welding defects and discontinuities without causing damage to the original part. NDT also known as non-destructive examination (NDE), non-destructive inspection (NDI) and non-destructive evaluation.

 

Quality Assurance (QA)

Quality assurance (QA) is any systematic process of determining whether a product or service meets specified requirements.

 

Quality Control (QC)

Quality control (QC) is a procedure or set of procedures intended to ensure that a manufactured product or performed service adheres to a defined set of quality criteria or meets the requirements of the client or customer. QC is similar to, but not identical with, quality assurance (QA). While QA refers to the confirmation that specified requirements have been met by a product or service, QC refers to the actual inspection of these elements.

 

Indication:

The response or evidence from a non-destructive examination.

 

Flaw:

An imperfection or discontinuity that may be detectable by nondestructive testing and is not necessarily rejectable.

 

Defect:

One or more flaws whose aggregate size, shape, orientation, location, or properties do not meet specified acceptance criteria and are rejectable.

 

Discontinuity:

A lack of continuity or cohesion; an intentional or unintentional interruption in the physical structure or configuration of a material or component.

 

Interpretation:

The determination of whether indications are relevant, nonrelevant, or false.

 

Evaluation:

Determination of whether a relevant indication is cause to accept or to reject a material or component.

 

Relevant Indication:

An NDT indication that is caused by a condition or type of discontinuity that requires evaluation.

As per ASME B&PV Code Section VIII Div. 1,

A Relevant Indication is one having a length greater than 1.5 mm.

 

Non Relevant Indication:

An NDT indication that is caused by a condition or type of discontinuity that is not rejectable. False indications are non-relevant.

As per ASME B&PV Code Section VIII Div. 1,

A Relevant Indication is one having a length less than 1.5 mm.

 

False Indication:

An NDT indication that is interpreted to be caused by a condition other than a discontinuity or imperfection.

 

Linear Indication:

A Linear Indication is one having a length greater than three times the width.

 

Rounded Indication:

A Rounded Indication is one of circular or elliptical shape with the length equal to or less than three times the width.