"Press-Twist caps" (PT caps) are closures for glass jars or bottles made of printed or varnished tinplate with very high barrier properties. The closure is pressed onto the thread of the glass container. At the first opening, the lugs on the glass produce the thread in the sealing compound of the PT cap. This results in a 100% secure tamper evidence.
Applications are mainly glasses with baby food and other pasteurized filling goods.
Manufacturing of Press-Twist Caps
Press-twist caps made of tinplate for glass closures are manufactured on a fully automatic production line comprising the following individual machines:
portal press with sheet feeder (KAPPA IV)
for punching raw caps with a multi-die tool directly from the tinplate sheet
The safety button is molded directly in the press for large-diameter caps.
cap forming machine (GAMMA III)
for the final processing of the drawn cups to twist-off closures in the following operations:
- pre-hemming the upper end of the cap (optional)
- pre-curling the upper end of the cap
lining and moulding machine (ALPHA I)
for injecting a sealing compound into the cap and gradual moulding of the sealing compound by means of a contoured moulding stamp
for drying the sealing compound (reduction of residual moisture)
for automatic or semi-automatic packaging of the caps in cartons