VOID-FORMING CORES OF KNOCK-DOWN FORMS FOR EMBEDDED BOLT CHANNELS IN REINFORCED-CONCRETE SLEEPERS Russian patent published in 1995 - IPC

FIELD: manufacture of reinforced-concrete products. SUBSTANCE: void-forming cores of knock-down forms for embedded bolt channels in tail supports have a housing bearing against an embedded washer with a centering recess trapezoidal in cross-section and provided with a window, with a tail having a square cross-section passed through the window. The tail is embraced by a remote member located between the tray and embedded washer. The embedded washer centering recess has inclined working surfaces that are engageable with equidistant surfaces of the housing curvilinear in cross-section, positioned at an angle of 4 to 15 deg relative to the vertical plane. The length of the diagonals of the embedded washer window and tail cross-section makes up respectively 0.80 to 0.99 of the length of the larger axis of the housing curvilinear section and diagonal of the remote member cross-section, whose height is lower than that of the tail by 1.02 to 1.18 time. The housing that is curvilinear in cross-section has vertical angular thrust slots located at an angle of 80 to 110 deg relative to one another. EFFECT: improved design. 7 dwg