US 11,724,417 B2
Method for producing concrete pipes
Ulrich Schlüsselbauer, Altenhof am Hausruck (AT)
Appl. No. 15/765,444
Filed by Ulrich Schlüsselbauer, Altenhof am Hausruck (AT)
PCT Filed Oct. 13, 2016, PCT No. PCT/AT2016/050260
§ 371(c)(1), (2) Date Apr. 2, 2018,
PCT Pub. No. WO2017/063010, PCT Pub. Date Apr. 20, 2017.
Claims priority of application No. A 50881/2015 (AT), filed on Oct. 16, 2015.
Prior Publication US 2018/0297234 A1, Oct. 18, 2018
Int. Cl. B28B 21/10 (2006.01); B28B 21/76 (2006.01); B28B 21/90 (2006.01)
CPC B28B 21/765 (2013.01) [B28B 21/10 (2013.01); B28B 21/90 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method for producing a concrete pipe from pourable wet concrete, wherein the concrete pipe has a pipe body with a predetermined cast pipe body volume, said method comprising:
providing a mold with a core and a mantle that is divided lengthwise, said core and said mantle defining a molding space therebetween with a volume greater than the predetermined cast pipe body volume, wherein said core extends above a height of an upper end of the concrete pipe to be formed, and upper and lower mold sleeves that terminate the molding space at a bottom and a top thereof;
pouring pourable wet concrete into the molding space so as to form the pipe body; and
demolding the pipe body after curing of the concrete by opening the mantle;
wherein the pourable wet concrete is poured into the molding space in a predetermined quantity with the upper mold sleeve removed,
wherein the predetermined quantity of the pourable wet concrete has a volume that is greater than the predetermined volume of the pipe body and that is determined as the predetermined volume of the pipe body plus a predefined setting volume that is determined based on setting behavior of the wet concrete; and
the method further comprises
pressing the upper mold sleeve as a closed ring in a shaping manner into an end face of the pipe body after said pouring and before said demolding, and after the volume of the pourable wet concrete has reduced to equal the predetermined volume of the pipe body, wherein none of the pourable wet concrete leaves the mold; and
allowing a setting time to elapse with the upper sleeve remaining removed after the pouring and before the pressing of the upper mold sleeve, wherein the setting time is of sufficient duration such that during the setting time, for at least a period of minutes, air bubbles ascend and leave the pourable wet concrete so as to cause the pourable wet concrete to be reduced in volume after the setting time is elapsed by the predefined setting volume to a volume equal to the predetermined volume of the pipe body between the core and the mantle.