Paint defect, often caused by air bubbles, which pits the painted surface, most commonly when paint is sprayed. The trapped air bubbles break, leaving a small hole in the paint surface. Slowly evaporating solvents can also cause this problem. Multiple coats of paint help to prevent it.
Pinion
Small diameter gear that is engaged with a larger gear to be used, for example, in transmissions.
Pinnacle
Projecting or ornamental cap on the high point of a roof.
Pinnate leaf
A series of leaflets arranged on either side of a central stalk.
Pinned file teeth
Material particle clogged file teeth.
Pintle
(1) Pin or bolt upon which another part turns. (2) Vertical peg used as a hinge pin on a gate. (3) Wood post base of cast iron or metal.
Pipe
A cylindrical hollow tube, used to convey water, gas, oil, water, etc, which come in varying materials, thicknesses and lengths. Natural gas and steam pipes up to 750 degrees F are made of carbon steel. Chrome-molybdenum low alloy steel is often used for temperatures above 750 degrees F. Water pipe is most often made of polyvinyl chloride. Some stainless steels, for example grave 311 H stainless, are also used for high temperatures while other stainless steels are used when pipe systems must be kept clean.
Pipe boot
A prefabricated flashing piece used to flash around circular pipe penetrations. Also known as a Roof Jack. Click here for an example.
Pipe bushing
Short pipe which has threading on the inside and outside diameter, along with wrench flats, for turning, at one end. Bushings can be used to change pipe sizes when other fittings cannot be used.
