Process for application of free-flowing material on the inner surface of a tube blank and device for performing the process

A device for application of a free-flowing material to the inner surface of a tube blank with a continuous, at least approximately cylindrical hollow space, comprising:

• feeding means for a continuous carrier gas flow laden with the material;
• a passage element (1) providing a passage space (2) for the laden carrier gas flow having an inlet end and an outlet end;
• said feeding means including a feed pipe (7) for the laden carrier gas flow having an outlet mouthpiece (16) directed to the inlet end of the passage space (2);
• guide vanes (3) placed in the passage space (2) between the inlet and outlet ends thereof and forming a swirl producing device for the laden carrier gas stream;
• the outlet end of the passage space (2) being adapted to axially direct to the hollow space of the tube blank the laden gas flow provided with its swirl;
• several jets (4) situated near the outlet end of the passage space (2) distributed evenly on its periphery, each being suitably fastened on one of the guide vanes (3);
• means (13) for feeding to the jets (4) a continuous gas stream which is not laden with the material;
• and the jet or jets (4) being skewed in relation to the axis (6) of the passage space (2) of the passage element (1) for producing at least one gas flow flowing helically at the inner surface of the hollow space of the tube blank and having the same direction of rotation as the swirl of the laden gas flow.