Open AccessIncrease of the efficiency in hot gas welding by optimization of the gas flow
Author(s) -
Johannes Schmid,
Dennis F. Weißer,
Dennis Mayer,
Lothar Kroll,
Matthias H. Deckert
Publication year - 2022
Publication title -
technologies for lightweight structures
Language(s) - English
Resource type - Journals
ISSN - 2512-4587
DOI - 10.21935/tls.v5i1.154
Subject(s) - nozzle , welding , materials science , flow (mathematics) , composite material , mechanical engineering , mechanics , engineering , physics
The standard hot gas welding process uses a nozzle system consisting of multiple round tubes. With the top nozzle system, the weld seam is encapsulated to minimize heat loss and allow better control of the hot gas flow. This significantly reduces the required heating time of the polymer. Temperature measurements and welding tests with plates of various thicknesses and burst pressure specimens are performed to verify the improvements of the top nozzle. For polyamides with different base polymers and different glass fiber contents, an average reduction in heating time of up to 50 % is possible on average. The achieved weld strengths or burst pressures for the tested materials are comparable or higher with the top nozzle system. The top nozzle makes the process more economical due to a short cycle time and lower gas consumption. It can be added to existing hot gas tools. In addition, a larger process window, shorter heating time and higher achievable temperatures with the top nozzle lead to a higher acceptance of hot gas welding in industries. New weld able materials in turn open up new application areas and markets.