As part of our new Tissue/Paper retail course offerings, we’re excited to announce that a series of new courses focused on the Yankee Dryer are now available. The new courses are listed below.
The Yankee dryer is a large, steam-heated, pressure vessel that is used in the production of tissue grades. Two critical operations occur at the Yankee – the sheet is dried to its final moisture target, and it is creped to add bulk, stretch, and softness to the sheet. The design and construction of Yankee dryers has evolved over time to optimize these two operations and also provide a safe work environment for the people who work around them. This course describes the major external and internal components of a Yankee dryer installed on a tissue machine, and the purpose or function of each component.
The Yankee dryer is a large, steam-heated, pressure vessel that is used in the production of tissue grades. After the tissue sheet is dried by the Yankee dryer and Yankee hoods to its final moisture target, it is creped and removed from the Yankee by the creping doctor. The “dry creping” process is responsible for the bulk, stretch, and softness that are desirable in tissue grades. This course describes what happens to the sheet during dry creping, factors that influence dry creping results, the design and operation of the creping blade, and blade angles and sheet angles associated with the creping blade.
This course describes the steam distribution and condensate removal equipment found in a Yankee dryer. It discusses how the steam pressure inside the dryer is controlled, how thermocompressors operate, and two common methods used to control the flows of steam and condensate through a Yankee dryer.
This course discusses the purpose of the Yankee dryer coating, and describes how the coating affects the drying and creping processes on the Yankee dryer. It also covers the history of Yankee coating, Yankee coating theory, the purpose and delivery of the coating ingredients (adhesives, release agents, and modifiers), and the set up of the Yankee sprayboom and glue box.
This course covers some general safety guidelines for working on or around a Yankee dryer. It describes the importance and purpose of following approved warm up and cool down procedures, doctor blade safety guidelines, steam pressure limits and relief valves, shell thickness considerations, and the influence of thermal spray coatings. It ends with discussions on the importance of regular maintenance, inspections, repairs and alterations, and detailed record keeping.
This course describes the equipment and processes responsible for supplying dry, heated air to, and removing humid exhaust air, from the Yankee hoods on a typical, modern Yankee dryer. Using a two-hood setup as a basis, it describes the equipment used to supply, recirculate, and exhaust the air in the hood air system. Gas burner operations, cross-machine moisture profiling, heat recovery equipment, and hood balancing are also covered.