PURPOSE: To provide a liquid transportation unit having the capacity of corrosion resistance and wear resistance by covering the outside of a graphite tube with alminum and sintering and by forming a linear explosion flame spraying layer made of metal having a high melting point and a high hardness in the inside surface of the sintered member.

CONSTITUTION: An aluminum covering 30 is installed on the outside of a graphite tube 10. The aluminum covered tube is sintered. Then, a wire made of iron and molybdenum is vertically inserted through an inside surface 17A of the tube 10 which forms the bore 17 of the tube 10 and a high current is applied, thereby forming a layer of linear explosion flame spraying. After sintering, the graphite is burned and the flame spraying metal is stabilized. A layer of linear explosion flame spraying having a high hardness and high melting point, for example, tungsten, is formed and double-layered, thereby producing an inside surface 17A of the tube 10 for a liquid transportation unit having the capacity of corrosion and wear resistance.