A process for the degradation of residual stresses in pipe - blanks from concrete and apparatus for carrying out the method

摘要

Apparatus for forming a concrete pipe comprises a pipe form, a rotatable material distributor, a non-rotatable core and vibrators attached to the core for vibrating material in the pipe form, the distributor and the core being selectively engageable and disengageable, and independently movable relative to the pipe form into and out of the pipe form. The vibrators are spaced axially along the interior wall of the core and each is selectively actuable. The core is moved by means of an hydraulic cylinder having a piston therein, the piston rod having a support platform for the core the reon.