Why does the vial freeze-dried to break the bottle? How to solve it?

  The vial bottle is the main form of packaging for sterile powdered medicines, and it is used in large quantities. At the same time, vacuum freeze-drying technology has developed rapidly in China in recent years. After nearly ten years of market competition and optimized combination, more than 10 professional manufacturers of vacuum freeze dryers have been formed. The technical performance of the pharmaceutical vacuum freeze dryer has been basically mature, and the corresponding industry standards have been formulated in China. Judging from the problems in actual production, since the use of domestically produced vials, it has been found that the problem of broken bottles during the freeze-drying process is relatively prominent, and the relevant departments have done a lot of work, starting with the quality of the process, equipment, and vials. Finally solved this long-standing problem.

First, the reasons for equipment manufacturing
At present, there are still many shortcomings in domestic freeze dryers. Individual enterprises are still in the structure of imitation foreign freeze dryers, and they do not have the principle of design and manufacture. Due to the different technical qualities, different design structures and manufacturing processes, there is no uniform standard. Some manufacturers have poor flatness of the shelf, especially for large-area shelves. When the tampon is finished after lyophilization, the pressure distribution is uneven, causing individual bottles to be crushed.
Second, the quality of the vial itself
This is an important factor affecting the rate of freeze-drying. We know that the vials need to be ultrasonically cleaned and autoclaved to remove the heat source before filling. No matter which process, the vials are a test. The intensity of the ultrasonic wave during cleaning and the impact of water vapor have a certain influence on the glass, and the uneven distribution of the temperature of the tunnel oven is prone to sudden heat and quenching, which is a major damage to the poor quality of the vial. Perhaps the appearance of the bottle can not be seen with the naked eye, but it may produce tiny cracks, so that it is not enough to withstand the temperature changes during the subsequent freeze-drying process. The bottlenecks of different degrees in the domestically produced bottles have been severely affected, and even more than 10%, and the bottle breaking rate of the good zulin bottles in China is far from the imported vials.

Third, the impact of freeze-drying process
While investigating the quality of the vials, we focused on the freeze-drying process and analyzed the reasons for the broken bottles. Usually, the glass bottle has a large tolerance to temperature when it is uniformly heated without being broken, such as baking in an oven, or freezing in an environment of tens of degrees Celsius below zero. However, if the temperature of different parts of the same bottle (especially the bottom of the bottle) changes rapidly or suddenly, a relatively large temperature difference is formed, and at this time, various parts of the bottle are subjected to different expansion forces, when the force is applied. Exceeding the bearing capacity of the glass will inevitably lead to damage to the glass.
This situation is very easy to occur during the freeze-drying process. The key to solving the problem of chipping and de-stacking is to reduce the temperature difference between the various parts of the glass bottle. On the freeze-drying process curve, the temperature line interval between the shelf temperature curve and the sample temperature curve is reduced. This can be achieved by vacuum control and temperature control in actual operation.

Fourth, detection means
In terms of entering the factory inspection, many pharmaceutical companies still do not have the relevant testing methods for the vials, and often refer to the technical parameters provided by the packaging plant, and do not combine the actual conditions of the vacuum freeze dryer. It is recommended to consider the necessary inspection of the quality of the vials. In view of the impact of the hot and cold changes on the vials, the thermal shock test of the RCY-02 glass bottle thermal shock tester is required.
For the case of the bottom of the vial, the main reason is that the stress concentration in the bottom part of the bottle should be checked by the YLY-02 polarized stress meter for residual stress. In addition, the uniformity of the wall thickness of the vial will also affect the stability of the product. The thickness of the bottle bottom wall can be tested by the CHY-B wall thickness gauge.