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When the content of hydrogen is too much in titanium tube, it will make the impacting toughness and notch tensile strength sharply decrease because of the brittleness, so the hydrogen content is not more than 0.015% in titanium pipe. In order to reduce the amount of hydrogen absorption, the fingerprints, rolling mill marks, grease and other residues on parts should be removed before heat treatment, the heat treatment furnace atmosphere should not have water vapor. If the hydrogen content of titanium tube exceeds the allowable value, it must be removed by vacuum annealing. The vacuum annealing of hydrogen is generally in the 760 - 538℃, it should be maintained 2 - 4 hours under the pressure of 0.066Pa.

When the temperature does not exceed 540℃,the oxide film on titanium tube surface will not be significantly thickened. While in the higher heat treatment temperature ( more than 760 degrees ), the oxidation rate will be accelerated, and the oxygen will go deep into the material to from the diffusion layer - the pollution layer. Oxygen contamination layer has a high brittleness ratio which leads to crack and damage on the surface of the parts. Removing the contamination layer of oxygen has machining methods (such as sandblasting, the real cutting), or pickling, milling and other chemical methods. In heat treatment, the heating time should be shorted as much as possible, it also can be carried out in a vacuum furnace or the heating furnace of inert gas (argon, nitrogen, etc.). The suitable application also can avoid or reduce the pollution caused by the heating of the titanium pipe parts in the air furnace.