Pittsburgh-Des Moines Steel Co.

The Pittsburgh-Des Moines Steel Company (originally the Des Moines Bridge and Iron Company), and often referred to as Pitt-Des Moines Steel or PDM was an American steel fabrication company. It operated from 1892 until approximately 2002 when its assets were sold to other companies, including CB&I (formerly Chicago Bridge & Iron Company).

Source: Wikipedia — Pittsburgh-Des Moines Steel Co. (CC BY-SA 4.0)