• Plastic caps – Qualification criteria for plastic bottle caps

Plastic caps – Qualification criteria for plastic bottle caps

⑴Specification requirements:
①Internal dimensions (±0.15mm): thread inner diameter, inner plug outer diameter, top wall thickness
②External dimensions (±0.30mm): the outer diameter of the cover, the overall height of the cover
③Other indicators: single weight (±0.10g)

⑵Appearance requirements:

① Cover surface: full molding, complete structure, no material shortage, no obvious damage, burrs and deformation;
②The color of the cover body: it conforms to the allowable limit of the standard sample, and the color is uniform;

28mm flip top cap (3)

③Sealing ring: no damage, deformation, strain;
④Side seal and top seal: no air bubbles or damage;
⑤Thread: Slight strain on the thread at the non-starting point is allowed, not less than the lower limit of the inner diameter of the thread;

⑥Connecting bridges (tangent points): no breakpoints, adhesions or not full;

⑦ Gate (injection cover): no perforation or cracking, no obvious gate residue or depression;
⑧ Pollution: no oil, dirt, rust, impurities;
⑨Printing: The pattern is clear, there are no defects such as missing printing, missing printing, etc., which meets the allowable limit of poor color registration, cross-inking, and pattern color, and the allowable center deviation of partial printing is ±0.3mm.

(3) Printing pattern adhesion performance:
①Hot water immersion method (hot filling cover): no obvious discoloration
② Peracetic acid soaking method (sterile cover): no obvious decolorization
③Tape sticking and peeling method: no obvious discoloration

⑷ Sealing performance:
① 700kPa×1min, boost speed 35kPa/sec, no air leakage or tripping
②LB angle (leakage angle - broken ring angle):
>0, squeeze the bottle body before opening the cap and breaking the ring without water escaping

⑺ Physical properties of anti-theft ring:
①Covering performance: the cover body and anti-theft ring will not be deformed, broken or retracted after the cover is closed;
② Anti-theft performance: After opening, the connecting bridge should be obviously damaged;
③Opening torque (lbf.in): ring breaking torque (lbf.in)
Hot charging cover (pressure): 13~18 5~9
Hot charging cover (Note): 15~18 5~9
Sterile cover: 10~16 8~12
Injection water cap: 6~14 5~9
Compression plastic water cover: 6~14 5~9

Post time: Nov-22-2022