| 摘要 |
In a process for partial filling and sealing portable plastic containers for liquefiable or solidifiable fuel gases, the container and the gas are held at a temp. such that the gas under atmos. press. has a very low vapour press. so that the container can be filled with air without perceptible vapourisation for a few seconds, the stopper is pressed firmly against its seat while it is welded by an ultrasonic source of 20-40 kHz, the plastic material of the container and the stopper being one with a low thermal conductivity of about 0.17 k cal/m3/hr/degree C. such as a polycarbonate of Bisphenol A. It is convenient to solidify the gas so that it can be supplied to the container in the form of a tablet of appropriate size. The use of solid gas and sealing the containers ultrasonically enables lighter containers to be made at high output rates. |
