Bottle closure supplier said that Anti-theft bottle caps generally use polyolefin as the main raw material, which is processed by injection molding, hot pressing and other processes.
Bottle closure supplier said that in order to ensure that the sealing of the product is up to the standard, it is necessary to carry out certain testing on the bottle cap.
Bottle closure supplier:How to test the tightness of anti-theft bottle caps?
The following is a detailed introduction to the lids made by Jinding in Lianyungang City.
1. Standard test methods
Bottle closure supplier said that The national standard GB/T 17876-1999 specifically stipulates the detection problems of this anti-theft bottle cap, such as the cap opening torque, thermal stability, drop resistance, leakage and sealing performance.
Among them, the evaluation of sealing performance and bottle cap opening and tightening torque is an effective way to solve the sealing performance of anti-theft bottle caps.
Bottle closure supplier said that According to the different uses of bottle caps, there are different regulations for the measurement methods of non-air caps and air caps.
If there is no air cap, cut off the anti-theft ring (strip) from the bottle cap, use it to seal with a rated torque of not less than 1.2NM, test it with a seal tester, pressurize it to 200kPa, keep the pressure underwater for 1 minute, and observe whether there is leakage Air or trip.
The air cap is pressurized to 690kPa, keep the pressure underwater for 1 minute, observe whether there is air leakage, then increase the pressure to 1207kPa, keep the pressure for 1 minute, and observe whether the cap is tripped.
2. Detection application
Bottle closure supplier said that Mainly use Labthink’s “LSSD-01 Leakage and Sealing Strength Tester” as an example to introduce.
The instrument can be professionally used for quantitative determination of leakage and sealing performance of various standard anti-theft bottle caps (with and without gas caps) with a thread diameter of 28mm and 38mm.
Bottle closure supplier said that Tripping strength and indicators such as sealing, compression resistance and burst resistance of the entire bottle body are evaluated and analyzed.
Bottle closure supplier said that Equipped with a special “anti-theft bottle cap sealing performance test device”, the anti-theft bottle cap is linked and packaged with a connecting unit, placed in a transparent observation tank, and the test is started after setting test conditions such as test pressure or leakage, and the instrument automatically performs the test.
Test data such as pressure and leakage can be displayed directly on the LCD screen. At the same time, it can also be judged by transparent observation of the air bubbles in the tank.
3. Summary
The sealing performance of the anti-theft bottle cap is the main factor affecting the packaging leakage and product deterioration. By reasonably controlling the sealing performance, it can ensure its good opening performance and avoid leakage.
What are the reasons for the shrinkage of anti-theft bottle caps?
Bottle closure supplier said that Due to the volume shrinkage of the anti-theft bottle cap, the surface raw materials at the wall thickness are pulled in.
After cooling, there are depression marks on the surface of the finished product, which mostly occur at the wall thickness.
What are the reasons for the shrinkage of the anti-theft bottle cap?
1. Process factors
(1) The holding pressure is not enough to overcome the strong resistance in the flow channel in the pressure holding stage, so that the pressure in the membrane is insufficient and effective feeding cannot be performed.
(2) The injection speed and pressure holding speed are too slow, so that the fluidity of the melt is not enough, and the speed is relatively slow.
Bottle closure supplier said that The melt that enters the cavity first cools down faster, and it is too late to use the holding pressure for feeding.
At this time, a higher temperature can be used. Injection pressure or raise the plastic.
(3) The holding time is too short, so that the melt flows back before the gate solidifies, resulting in insufficient product feeding.
(4) Bottle closure supplier said that The back pressure of the storage material is not enough, and the screw retreat speed is fast, so that the melt is not compact, and the shrinkage space of the product is large.
(5)Bottle closure supplier said that The mold temperature and hot runner temperature are too high, and the cooling time is prolonged.
When the cooling is not enough, the shrinkage of the product is large.
2. Mold factor
(1) Poor air trapping and exhausting of the mold, resulting in residual air in the cavity, less molten material for feeding, and large shrinkage of the product, the mold should be maintained and an exhaust slot should be added.
(2) Bottle closure supplier said that The demoulding is not smooth, resulting in the product being pulled down and dents appearing.
The mold should be maintained, polished or thimble should be added.
