Glossary of Terms
Blow Molding: A manufacturing process by which hollow plastic parts are formed. In general, there are three main types of blow molding. Extrusion blow molding, injection blow molding, and injection stretch blow molding
Bolt Ring: A closing device which requires a bolt and nut to secure the cover to the body of an open-head drum
Bottom: The bottom of a tight-head drum or pail
Bung: A threaded closure used on the head or body of a drum or tank
Bung Adapter for Coarse (Buttress) Threaded Drums: A buttress-threaded device that accepts an NPS threaded bung or other accessory
Buttress Thread: A design of thread profile (cross-section) which takes the form of a right triangle or slight modification of that form. It is usually positioned so that the right angle is at the bottom of the thread cross-section and adjacent to the neck of the bottle or flange finish. The horizontal leg of the right triangle is the bearing surface for a matching cap thread. Commonly referred to as coarse thread, and used on large bottles and plastic drums and pails
Capacity: The amount of space inside a container provided for a given amount of product
Chime: The top or bottom edge of the drum formed when the body and head of the drum are joined
Closure: A term used to describe a metal or molded cap, bung, or plug which effects a primary seal when properly applied to a container
Density: Weight per unit of volume of a substance, expressed in grams per cubic centimeter, pounds per cubic foot, etc.
D.O.T.: Department of Transportation. A governmental body regulating the shipment of materials on public rights-of-way
Factory Module (FM): Nationally recognized independent testing laboratory. Evaluates the ability of equipment to meet safety requirements under intended use
Flange: A permanently installed threaded drum component which receives a male threaded bung
Fluorination: The process of bonding fluorine gas to plastic. Inhibits the attack of certain kinds of products, and prevents plastic container paneling and distortion, reduces chemical permeation, odor emission, or flavor loss
Gauge: A standard measure of the thickness of steel sheet. The higher the number, the thinner the steel
Head: The top of a tight-head drum or pail
Head Space: The space between the level of the contents in the container and the underside of the head. It is intended to furnish space for expansion of product due to heat or other action after packing
Lever Lock Ring: Closing device for securing the cover to the body of an open-head drum. Relies on a lever-activated mechanism to bring the ends of the ring together
Lining: A coating, used in the interior of steel drums or pails, which protects the product from contact with the metal of the container. For more info, see here
NPS: National Pipe Straight threads used in steel drums. Most steel drums have both a 2″ and a 3/4″ NPS opening
NPT: National Pipe Thread is a U.S. standar for tapered threads used on threaded pipes and fittings
Open-Head: A drum or pail with removable cover
Plug: A threaded closure used on the head or body of a drum or tank. Also known as a Bung
Rolling Hoop: Reinforcement rings in the form of hooped expansions in the body of the drum. They strengthen the shell of the container
Silk Screen Printing: A printing method, that uses a pattern of an insoluble material, in outline on a finely woven fabric (the silk screen), so that when the ink is drawn across it, it is able to pass through the screen to the print medium in the desired areas only
Tight-Head: A type of drum or pail on which the cover does not come off. Access into the drum is accomplished through a threaded plug
Torque: Force in a circular motion as applied to a closure on a container, either to attach or remove the closure. See Foot-Pound
UN Specification: United Nations international standards for the transport of dangerous goods, adopted by the U.S. Department of Transportation (Title 49 of the Code of Federal Regulations)
Viscosity: The flow characteristic of a fluid. High viscosity fluids are thicker and flow more slowly