Piping Related Abbreviations (P)

PBE is an abbreviation of Plain Both Ends.
Plain Both Ends means that both ends of e.g. a pipe nipple are plain.
TOE / POE = Treaded One End / Plain One End
TOE / BOE = Treaded One End / Beveled One End
POE / BOE = Plain One End / Beveled One End
TBE = Treaded Both Ends
BBE = Beveled Both Ends

PED is an abbreviation of Pressure Equipment Directive arises from the European Community's Programme for the elimination of technical barriers to trade and is formulated under the "New Approach to Technical Harmonisation and Standards".
Its purpose is to harmonise national laws of Member States regarding the design, manufacture, testing and conformity assessment of pressure equipment and assemblies of pressure equipment.

PFD is an abbreviation of Process Flow Diagram.
A Process Flow Diagram is a schematic representation of the flow of fluids within the process as they travel between processing units. This diagram shows flow direction, but has no indication of the instruments and devices needed to control the process or to ensure safe operation.

PI is a mathematical constant that is the ratio of any Euclidean circle's circumference to its diameter. PI is approximately equal to 3.14. Many formulae in mathematics, science, and engineering involve PI, which makes it one of the most important mathematical constants. For instance, the area of a circle is equal to PI times the square of the radius of the circle.

PMI is an abbreviation of Positive Material Identification.
Positive Material Identification provides alloy chemistry and grade ID information instantly using a handheld tube-based analyzer without having to transport, alter, or damage the material. PMI is also used to ensure that the parent material in vessels and pipe spools is composed of the correct composition and once the component is welded that the correct filler material was used.

PREN is an abbreviation of Pitting Resistance Equivalent Number.
The Pitting Resistance Equivalent Number is a numerical value calculated based on the mass fraction of certain elements in the metal. It is an important parameter for quantitatively evaluating and characterizing the comprehensive corrosion resistance of stainless steel. It can be used to evaluate the ability of stainless steel to resist pitting corrosion in chloride environments. It is generally considered that a PREN above 32 is resistant to seawater corrosion.

PWHT is an abbreviation of Post Weld Heat Treatment.
Post Weld Heat Treatment is defined as one of heat treatments done after welding/machining to improve the chemical and mechanical properties of weldment or machined surfaces. In concept, PWHT covers many different potential treatments.