Method for producing concrete pipes

A method for producing a concrete pipe from pourable wet concrete, said method comprising:

• providing a mold with a core surrounded by a mantle, said mantle being divided lengthwise thereof, said core and mantle defining a molding space therebetween with a volume greater than a predetermined cast pipe body volume of a cast pipe body of the concrete pipe, and said mantle having upper and lower mold sleeves that define top and bottom terminal ends of the molding space, the upper mold sleeve forming a closed ring, and said core extending above a height of an upper end of the concrete pipe to be formed;
• pouring a predetermined quantity of pourable wet concrete into the molding space with the upper mold sleeve removed so as to form the cast pipe body of the concrete pipe between the core and the mantle, the predetermined quantity of wet concrete having a predetermined volume that is determined as the predetermined cast pipe body volume of the cast pipe body plus a predefined setting volume determined based on setting behavior of the wet concrete;
• allowing passage of a setting time after said pouring of the predetermined quantity of the pourable wet concrete into the molding space with the upper mold sleeve removed during which air leaves the pourable wet concrete, the setting time being of sufficient duration such that during the passage of the setting time, for at least a period of minutes, air bubbles ascend in the pourable wet concrete and escape therefrom so that the predetermined quantity of pourable wet concrete is reduced in volume by the predefined setting volume so as to have a reduced volume equal to the predetermined cast pipe body volume;
• after the allowing of the passage of the setting time, when the volume of the pourable wet concrete has reduced to the predetermined volume of the cast pipe body, pressing the upper mold sleeve into an upper portion of the pourable wet concrete so as to shape an end face of the cast pipe body wherein none of the pourable wet concrete leaves the mold;
• and
• demolding the cast pipe body after curing of the concrete by opening the mantle.

A method for producing a concrete pipe from pourable wet concrete, wherein the concrete pipe has with a cast pipe body having a predetermined cast pipe body volume, said method comprising:

• pouring a predetermined quantity of pourable wet concrete into a vertical mold with a vertical core surrounded by a mantle, said core and mantle defining a molding space therebetween configured to receive the predetermined quantity of pourable wet concrete therein;
• said mantle being divided lengthwise thereof and having upper and lower mold sleeves that define top and bottom terminal ends of the molding space, the upper mold sleeve comprising a closed ring that is removed during said pouring of the pourable wet concrete;
• the predetermined quantity of wet concrete being in an amount that has a predetermined volume determined as the predefined cast pipe body volume of the cast pipe body plus a predefined setting volume of the pourable wet concrete that is based on setting behavior of the pourable wet concrete;
• after said pouring of the entire predetermined quantity of the pourable wet concrete into the molding space, allowing passage of a setting time with the upper mold sleeve removed during which, for at least a period of minutes, air ascends as air bubbles in the pourable wet concrete and leaves the pourable wet concrete, the setting time being of sufficient duration that, during the setting time, the predetermined quantity of pourable wet concrete reduces in volume by the predefined setting volume to a reduced volume equal to the predetermined cast pipe body volume;
• after said allowing of the passage of the setting time wherein the volume of the pourable wet concrete has reduced to the predetermined volume of the pipe body, applying the upper mold sleeve into an upper surface of the pourable wet concrete so as to shape the end face of the cast pipe body, wherein none of the pourable wet concrete leaves the mold;
• and
• opening the mantle;
• and
• demolding the cast pipe body after curing of the wet concrete.