To provide an LNG vaporizer that can easily perform PT inspection near the welding joint part of a heat transfer pipe and a lower header where a thermal load is repeatedly applied causing the problem of thermal fatigue strength and at the same time obtains a sacrifice anode effect due to the flame spraying covering of Al-Zn alloy or the like and further a sacrifice anode effect due to a sacrifice anode material.

In an LNG vaporizer 1, a panel 3 with an LNG channel and a cooling fin is welded between headers 6 and 7 being arranged up and down and sea water is allowed to flow down along the surface of the panel 3 for vaporizing LNG. In the LNG vaporizer 1, a welding joint part 5 between the lower header 7 and the panel 3 or an area 12 including the welding joint part 5 are allowed to remain as an inspection surface, and the flame spraying layer of a corrosion resistance metal covering 13 is executed to the entire surface of the upper and lower headers 6 and 7 and the panel 3.