Other kinds of welding. Some kinds of welding do not use an electric arc. They might use a flame, electricity without an arc, an energy beam, or physical force. The most common type of welding that does not use an arc is called gas welding.
TDW - Total Diamond Weight. A term usually used when there is more than one diamond in a particular piece of jewelry. The combined weight of all of the (diamond) stones.
Quick Answer. In the U.S. military, the abbreviation TDY stands for temporary duty. Temporary duty refers to the situation when a soldier or other employee is assigned to serve at a location that is not his permanent station. Generally, TDY assignments are shorter than six months in duration.