Passenger all-steel tire and turn up process in building process thereof

A turn-up process in a two-stage building process of the passenger all-steel tire, that is, a second turn-up process, wherein, comprising the following steps:

• finger-type sheets turn-down:
• forming a laminating assembly (101) after semi-finished products are laminated together on a laminating drum, and extending finger-type sheets (103) out to cover two ends of the laminating assembly (101);
• the semi-finished products comprise a ply of the all-steel carcass (41);
• beads sleeving:
• propelling bead propelling devices (104) to the laminating assembly (101) along the finger-type sheets (103) from two sides of the laminating drum, and sleeving the two beads (6) on an outer side of the laminating assembly (101) and positioning the beads (6) to predetermined positions by the bead propelling devices (104), pausing 2.5 to 3 s after the beads (6) are sleeved, and then returning the finger-type sheets (103) and the bead propelling devices (104) to original positions;
• after the beads sleeving, dividing the laminating assembly (101) into three portions by the two beads (6), that is, a first portion (1011) of the laminating assembly (101) located between the two beads (6) as well as a second portion (1012) and a third portion (1013) of the laminating assembly (101) respectively located on two sides of the two beads (6);
• and
• turn-up:
• inflating and expanding turn-up bladders (105) which are located at the two beads (6) on the two sides of the laminating drum to support the second portion (1012) and the third portion (1013) by the inflated turn-up bladders (105), wherein an inflation pressure of the turn-up bladders (105) is 0.4 to 0.5 Bar;
• propelling turn-up bladder squeezing devices (106) to the turn-up bladders (105) from two sides respectively to squeeze the turn-up bladders (105), so that the second portion (1012) and the third portion (1013) are turned up and laminated on the first portion (1011) to complete the turn-up;
• pausing 5 to 6 s after the turn-up, and then pressing turn-up positions of the laminating assembly (101) by a press roller under a high pressure of 0.2 to 0.25 Bar.