Abstract: The present invention produces a cold gas stream having a constant temperature and pressure. The gas stream is obtained from two initial streams, one being a liquefied gas and the other being a gas at ambient temperature. The liquefied gas stream is combined with the warm gas stream, causing the liquid to vaporize. The two streams are combined in proportions that yield a cold gas mixture having a desired temperature. The resulting cold gas mixture is directed into an insulated container having a volume significantly larger than the volume of the conduits through which the streams flow. The container therefore acts as a buffer to reduce pressure fluctuations in the stream. A temperature equalization coil is located in the interior of the container. The coil has one open end which communicates with the interior region of the container, the other end of the coil being connected to an outlet line.