| Butt-Weld Pipe | (english) The standard steel pipe used in plumbing. Heated skelp is passed continuously through welding rolls, which form the tube and squeeze the hot edges together to make a solid weld. |
| Butyl Stearate | (english) (BSO)A lubricant applied on electrolytic chromium coated steel |
| By Coil | (english) Selling term which refers to product sold in the form of a coil vs. cut plate. "Bi Coil" is also used in production to refer to coils vs. cut plate |
| By-Pass | (english) Manual control used to by-pass automatic valve if it fails or in an emergency. |
| Bending moment: | (english) A system of internal forces whose resultant is a moment. This term is most commonly used to refer to internal forces in beams. |
| Body force: | (english) An external force acting throughout the mass of a body. Gravity is a body force. An inertial force is a body force. |
| Brittle: | (english) A brittle structure or material exhibits low ductility, meaning that it exhibits very little inelastic deformation before complete failure. |
| Bacteria | (Environmental Engineering) One celled microorganisms which do not have a nuclear membrane. |
| Baghouse filter | (Environmental Engineering) A fabric filter device used to remove particulate air pollutants. |
| Biochemical oxygen demand (BOD) | (Environmental Engineering) The amount of oxygen required to oxidize any organic matter present in a water during a specified period of time, usually 5 days. It is an indirect measure of the amount of organic matter present in a water. |