A fitting used to connect a large pipe to a smaller pipe so that one edge of both pipes is aligned.

A heat recovery device used in a boiler to transfer heat in the combustion gases to feed water.

Currents caused by changing magnetic fields produced in armature and field cores of electrical machines that tend to interfere with the production of emf in the armature windings.

The ratio of a machine’s energy output to energy input. It may be expressed as a decimal or a percent. Efficiency equals the work output divided by the work input or the actual mechanical advantage (AMA) divided by the ideal mechanical advantage (IMA).

The powder or crust formed on a substance when moisture is evaporated from it.

The waste product of a process that is discharged to sewer or for further treatment.

The point on a stress-strain diagram where the curve starts to deviate from a straight line and after which the material will not return to its original shape.

The property that allows a material to deform under a load and return to its original shape after the load is removed.

Boilers in which heat is produced by electricity rather than fuel oil or gas. Heat is produced either between two electrodes or by resistance to the flow of electricity through a coiled conductor.

Furnaces in which the air is heated by passing directly over the electric heating elements. Electric energy is converted to heat using open wire resistance heating elements.

Electric heaters consisting of long, slender tubes, similar in appearance to fluorescent lamp fixtures. The tubes fit into fixtures, which can be hung from the ceiling or wall, or mounted flush with the ceiling. A reflector is mounted behind each tube directs the radiant heat into the space to be heated.

A conductor that emits or collects electrons in a cell.

The production of a chemical reaction by passing an electric current through an electrolyte.

A liquid or paste that conducts electricity as a result of the presence of positive or negative ions.

A temporary magnet made of a ferromagnetic core wound with insulated wire through which is passed an electric current. The current flow through the windings causes a magnetic field to build that will attract magnetic material.