If liquid nitrogen is not sealed well, it will volatilize at room temperature very quickly. In particular, during the freezing treatment of cotton swabs, the lid of the container cannot be properly closed due to the need for rapid freezing after liquid nitrogen is drawn. Causes the evaporation and waste of liquid nitrogen. To this end, we have improved the extraction funnel for the liquid nitrogen tank and are now described as follows:
1. Production method: take a piece of foam and make it about 3 cm tall, which is slightly smaller than the neck of the liquid nitrogen barrel. We call it the built-in cover, and the built-in cover is fixed on the neck of the taking funnel. When the funnel is placed in the bucket, the built-in cover just covers the liquid nitrogen bucket. In this way, after the liquid is taken, the built-in cover naturally covers the liquid nitrogen mouth.
2. Advantages: It is not necessary to cover the lid of the liquid nitrogen container during the cryotherapy process. It saves time and prevents evaporation of liquid nitrogen. Save costs and avoid waste. It is easy to operate and simple to produce.