Method of manufacturing tubes and device for carrying out the method

A method of manufacturing a tube, said method comprising the steps of:

• providing a tubular mold having an inner wall and a longitudinal axis;
• rotating the mold about its longitudinal axis;
• introducing a liquid binder into the tubular mold, said liquid binder being deposited on the inner wall of the rotating mold;
• introducing a powdered material into the tubular mold simultaneously with the liquid binder, said powder being deposited in the liquid binder on the inner wall of the rotating mold;
• and
• removing excess liquid binder from the mixture of binder and powder to form a green tubular body;
• characterized in that the method further comprises the steps of:
• successively and simultaneously introducing a second amount of liquid binder and powdered material into the tubular mold, said liquid binder and powdered material being deposited on the previously deposited mixture of binder and powder.

A method of manufacturing a tube, said method comprising the steps of:

• providing a tubular mold having an inner wall and a longitudinal axis;
• providing supply means for introducing powdered material into the mold;
• providing supply means for introducing liquid binder into the tubular mold;
• rotating the mold about its longitudinal axis;
• introducing a liquid binder into the tubular mold, said liquid binder being deposited on the inner wall of the rotating mold;
• separately introducing a powdered material into the tubular mold, said powder being deposited on the inner wall of the rotating mold;
• and
• removing excess liquid binder from the mixture of binder and powder to form a green tubular body;
• wherein the method further comprises the steps of:
• successively introducing an additional amount of liquid binder into the tubular mold, said liquid binder being deposited on the previously deposited mixture of binder and powder;
• and
• separately introducing an additional amount of powdered material into the tubular mold by continuously moving said powder supply means relative to the inner surface of the tubular mold, said additional amount of powder being successively deposited on the previously deposited mixture of binder and powder.

A method of manufacturing a tube, said method comprising the steps of:

• providing a tubular mold having an inner wall and a longitudinal axis;
• providing supply means for introducing a powdered material into the mold;
• providing supply means for introducing liquid binder into said tubular mold;
• rotating the mold about its longitudinal axis;
• introducing a liquid binder into the tubular mold, said liquid binder being deposited on the inner wall of the rotating mold;
• introducing a powdered material into the tubular mold after the liquid binder is introduced, said powder being deposited on the liquid binder on the inner wall of the rotating mold;
• and
• removing excess liquid binder from the mixture of binder and powder to form a green tubular body;
• wherein the method further comprises the steps of:
• introducing an additional amount of liquid binder into the tubular mold by continuously moving said liquid supply means relative to the inner surface of the tubular mold, said liquid binder being deposited on the previously deposited mixture of binder and powder;
• and
• introducing an additional amount of powder into the tubular mold after the additional amount of liquid binder is introduced by continuously moving the powder supply means relative to the inner surface of the tubular mold;
• said additional amount of powder being deposited on the liquid binder on the inner wall of the rotating mold.

A method of manufacturing a tube, said method comprising the steps of:

• providing a tubular mold having an inner wall and a longitudinal axis;
• providing supply means for introducing powdered material and a liquid binder, respectively and successively into said tubular mold;
• rotating the mold about its longitudinal axis;
• introducing a liquid binder into the tubular mold, said liquid binder being deposited on the inner wall of the rotating mold;
• introducing a powdered material into the tubular mold simultaneously with the liquid binder, said powder being deposited on the liquid binder on the inner wall of the rotating mold;
• and
• removing excess liquid binder from the mixture of binder and powder to form a green tubular body;
• wherein the method further comprises the steps of:
• introducing an additional amount of liquid binder into the tubular mold, said liquid binder being deposited on the previously deposited mixture of binder and powder;
• and
• introducing an additional amount of powdered material into the tubular mold simultaneously with the second amount of liquid binder by continuously moving said respective supply means relative to the inner surface of the tubular mold, said additional amount of powder being deposited in the liquid binder on the previously deposited mixture of binder and powder.

A method of manufacturing a tube, said method comprising the steps of:

• providing a tubular mold having an inner wall and a longitudinal axis;
• providing supply means for introducing a solid phase material and a liquid material, respectively, into the tubular mold;
• rotating the mold about its longitudinal axis;
• introducing a liquid phase material into the tubular mold, said liquid phase material being deposited on the inner wall of the rotating mold;
• separately introducing a solid phase material into the tubular mold, said solid phase material being deposited on the inner wall of the rotating mold;
• and
• removing excess liquid phase material from the mixture of solid phase material and liquid phase material to form a green tubular body;
• wherein the method further comprises the steps of successively introducing said solid phase material and said liquid phase material into the tubular mold by continuously moving the supply means relative to the inner surface of the mold.