OPEN RACK TYPE VAPORIZER

PURPOSE: To reduce excessive freeze-up generated below a heat exchanger panel by idly fitting a tubular cap provided with a small hole on the top into an inner tube of a stuff in-tube which constitutes the heat exchanger panel by way of a specified clearance. CONSTITUTION: LNG, which is supplied to each stuffing tube 10 of a heat exchanger panel from a lower header tank 11, flows in an inner tube 13 and rises there and enters a tubular cap 20 from the upper end of the inner tube 13 so that the LNG may partially flow into the tubular cap 10 directly from a small hole 21 on the top. The other LNG flows down in an inner ring-shaped passage formed with the tubular cap 20 and the inner tube 13 and rises in an outer ring-shaped passage formed with the inner surface of the stuffing tube 10 and the tubular cap 20 from the lower end of the tubular cap 20 and is discharged outside as a vapor gas by way of an upper head tank 12. In this case, the shape of a secondary heat transfer surface produced by a plurality of stuffing operations of the stuffing tubes 10 function on heat exchange effectively.