Improvement of the Acoustic Characteristics of Pneumatic Mechanisms for Contact Welding Machines


Annotation:

Welding production forms the basis of assembly production in many branches of industry. Welding equipment is the most numerous in the environment of assembly of transport engineering units. This equipment is used both at the initial stage of assembly operations and at the final stage.  The most common machines are single-point and multi-point welding with pneumatic drive. Traditional disadvantage of welding machines using pneumatic drives is the presence of intense acoustic flows at the outlet of the energy carrier, the operating sound level of which significantly exceeds the established sanitary norms and worsens personnel working conditions. Among the sources of aerodynamic flows in contact welding machines, the most relevant noise is during technological release of energy from the pneumatic mechanisms of the welding machines control systems, including the existing fleet of contact welding machines. Standard noise mufflers in the contact welding machines, the acoustic elements of which are made in the form of porous metal bushings or pots, are working efficiently for a short period of time up to 200 hours, both domestic and foreign companies Festo, Camozzi, Pneumax. The reason is that when pulsed, technological release of compressed air containing oil particles, in the presence of external dust sources, the channels of porous sound-absorbing elements are clogged with a suspension of oil with the above specified particles and condensate. This leads to an increase in the hydraulic resistance of the muffler path, an increase in the back pressure in the silencing chamber, and, as a result, to the destruction of the acoustic element, which requires frequent replacement of the muffler.
The results are presented concerning the development of new chamber mufflers for contact welding machines, which efficiently reduce noise, operate without maintenance for more than fifteen years without requiring replacement. They are recommended for various branches of industries operating pneumatic systems for various purposes.

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DOI: 10.24000/0409-2961-2021-2-20-23
Year: 2021
Issue num: February
Keywords : акустические характеристики contact welding machines pneumatic valves compressed air outlet porous sound-absorbing element noise mufflers chamber slot mufflers
Authors:
  • Ivanov Yu.V.
    Ivanov Yu.V.
    Dr. Sci. (Eng.), Assoc. Prof., Head of the Department, ivsot@mail.ru Udmurt State University, Izhevsk, Russia