PROCESS CONTROL: Is a general term used to encompass the actions and documentation, as required by official
directives or logic, that are necessary for a NDI method to be effective in detecting conditions of interest (e.g., cracks,
foreign objects, corrosion, alignment of parts, thickness of parts/coating and pressure/vacuum leaks).
PROCESSING DEFECTS: Defects occurring in the material during any of the processing stages from molten metal to
the finished product.
PROCESSING, FILM (RT): A series of operations, such as developing, fixing, and washing, associated with the
conversion of a latent image into a stable visible image.
PROCESSING UNIT (RT): A series of tanks forming a single unit for holding chemical solutions used during
PROCESS INSPECTION: To establish correct manufacturing procedure by inspection methods, and then by periodic
inspection to insure that the process continues to operate correctly.
PRODS (MT): Hand held electrodes attached to cables to transmit the magnetizing current from the source to the part
PROGRESSIVE AGING: Aging by increasing the temperature in steps or continuously during the aging cycle.
PROGRESSIVE FORMING: Sequential forming at consecutive stations either with a single die or with separate dies.
PROJECTOR (RT): See exposure device.
PROOF LOAD: A predetermined load, generally some multiple of the service load, to which a specimen or structure is
submitted before acceptance for use.
The stress that will cause a specified small permanent set in a material.
A specified stress to be applied to a member or structure to indicate its ability to withstand service loads.
PROPAGATION: Advancement of a wave through a medium.
PROPORTIONAL LIMIT: The maximum stress at which strain remains directly proportional to stress.
PROTECTIVE APRON (RT): Apron made of attenuating materials, used to reduce radiation exposure.
PROTECTIVE MATERIAL (RT): Shielding material used for the purpose of radiation protection.
PROTON: An elementary particle with a single positive electrical charge and a mass approximately 1847 times that of
the electron. The atomic number of an atom is equal to the number of protons in its nucleus.
PSIGG: Pounds per square inch; gauged air pressure gauged by a regulator.
PT: Symbol for the liquid penetrant method of nondestructive testing/inspection.
PUBLIC DOSE: The dose received by a member of the public from exposure to radiation.
PULL CRACKS: In a casting, cracks that are caused by residual stresses produced during cooling, and that result from
the shape of the object.