METHOD FOR MANUFACTURING A SOUND-ABSORBING DEVICE FOR A TURBOJET ENGINE Russian patent published in 2023 - IPC F02C7/24 

FIELD: aircraft engine building.

SUBSTANCE: sound-absorbing devices for turbojet engines. The method includes manufacturing autonomous sound-absorbing sections, fastening them around the circumference to each other with flanges on annular frames and/or overlays between adjacent sections. During the manufacture of sections, a prepreg of the rim or out-of-rim wall of the section blank is placed in the cavity of the body of the assembly device with adjoining to the bottom and ends of the cavity of the body of the assembly device with the formation of transverse flanges from the ends of the prepreg, the blank of the sound-absorbing filler section in the form of tubular elements with elastic mandrels inside, and on the last and part of the transverse flanges - the other wall of the section blank, on which the cover of the assembly device is installed. They are clamped along the transverse flanges between the cover and the body of the assembly tool. Then the resulting assembly is installed in the oven, heated and after curing, cooled, removed from the oven, and the resulting section blank is removed from the assembly fixture. At the same time, at least one of the elements of the sound-absorbing section blank, the prepreg of which differs in the chemical composition of the constituent components and/or the curing temperature from the chemical composition of the components and/or the curing temperature of the prepreg used to manufacture another or other elements of the section, is made separately by laying the prepreg into the cavity of the body of the device with subsequent curing, and its connection with another or other elements of the sound-absorbing section in the cavity of the body of the assembly device is carried out through an adhesive laid on the contact surfaces of the pre-cured element and another or other elements of the sound-absorbing section mating with it.

EFFECT: manufacturing a reliable and high-quality design of a PCM device with different physical and chemical and physical and mechanical characteristics and thermophysical properties, and reduction of the cost of production.

2 cl, 5 dwg