| 摘要 |
The exhaust pipe comprises an inner pipe, permeable to gas in radial direction, which is provided with a casing (4) and possibly with a noise-suppressing material (3) such as mineral wool inside the casing. The pipe (2) is produced by utilizing prefabricated perforated, generally cylindrical rings of strip material, said rings when considered in axial section having outwardly concave cross section (5), with cross-sectional legs (6, 7) of different lengths. The rings (10) are placed axially beside each other and are flexibly jointed to each other by the longer flange (6) of one ring (10) being upset over the shorter flange on an adjacent ring (10) to form a joint (1) of ball-and-socket type. The pipe (2) can be quickly and rationally manufactured with automatic equipment to the desired length and can be bent to the desired shape without noticeably altering the axial length of the pipe. |
