摘要 |
The device is composed of several separate elements consisting of at least one central tubular element connected, on one side, by means of a first ball-and-socket joint and a first compensator to a first connector supplying preheated air and on the opposite side, by means of a second ball-and-socket joint and a second compensator to a second connector. In order to reduce the length of the device, the second joint is oriented in the opposite direction to the said first joint, its center of curvature being located on the axis of the said second connector on the inside of the latter. |