Transition Pieces / Ductwork

Ductwork assemblies may include fabricated elbows, tees, and straight sections of ductwork, in carbon steel or stainless steel, and in diameters of 42″ or larger. Transition pieces are normally used to join ductwork of dissimilar cross-sections and sizes. Media passing through the transition piece can be air, liquid, gasses, dust, dirt, chemicals, etc..

Ductwork encompasses a number of control devices (such as longitudinal duct, elbows, dampers, concentric reducers, eccentric reducers, expansion joints and support systems) that either deliver or carry air, exhaust gases, vapors, fumes, smoke, and/or particulate matter in a number of ventilation applications. Within this realm, U.S. Bellows and Sweco, offer custom-designed expansion joints and fabricated ductwork assemblies. These assemblies, which can encompass fabricated elbows, tees, and straight ductwork sections, are available in carbon steel or stainless steel, with diameters of 42″ or larger. The flexibility of these duct sections is enhanced with the inclusion of fabric or metallic expansion joints, catering to both rectangular and round configurations. U.S. Bellows and PT&P extend their expertise to specialized pipe supports, spring hangers designed for large-diameter ductwork, and comprehensive pipe stress analysis through CAESAR II software.

Key Features of U.S. Bellows and Sweco Ductwork and Transition Pieces:

  • Material Composition: Primarily crafted from stainless steel or carbon steel.
  • Expansion Joint Options: Inclusive of fabric or metallic expansion joints.
  • Configurations: Available in both round and rectangular shapes.

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The air within process ductwork may operate under ambient conditions or reach temperatures of up to 900 °F (482 °C). These ducts exhibit a wide range in size, spanning from 2 ft diameter to 20 ft diameter or rectangular configurations measuring up to 20 ft by 40 ft. Notably, larger process ducts may accumulate dust, weighing 2 to 4 tons per linear foot based on the slope.

In the realm of structural process ductwork, considerations extend to industries such as cement, lime, and lead. Rectangular ductwork falls under the purview of the ASCE’s guidelines for “The Structural Design of Air & Gas Ducts for Process Power Stations and Industrial Applications.”

The longevity and effectiveness of ductwork rely significantly on the materials used in its construction. In challenging industrial settings, galvanized steel, renowned for its durability, is applied, whereas aluminum, prized for its lightweight properties, provides an apt solution for commercial environments. US Bellows underscores its dedication to excellence by highlighting the synergy of precision engineering and top-tier materials, resulting in the production of durable and resilient ductwork.

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