Method and machine for producing titanium cobbles

A method of producing titanium cobbles for use for at least one of a titanium ingot raw material, a superalloy, an additive material for an aluminum alloy, or an additive material for steel, the titanium cobbles being titanium-containing particles, each containing 50% by mass or more of metal titanium, and having a maximum size of 50 mm or smaller and an aspect ratio of 5 or lower, the aspect ratio being obtained by dividing the maximum size by a minimum size, the method comprising:

• a preparation step of preparing a scrap material containing 50% by mass or more of metal titanium;
• a first crushing step of roughly crushing the scrap material using a first crusher;
• a second crushing step of crushing the scrap material, which has been roughly crushed in the first crushing step, using a second crusher;
• a dust collection step of collecting fine dust of the scrap material generated in the second crushing step;
• a first classification step of classifying products obtained by crushing the scrap material, which have been generated in the second crushing step, into medium particles with particle sizes of 3 mm or larger and 50 mm or smaller, large particles with particle sizes larger than 50 mm, and small particles with particle sizes smaller than 3 mm;
• a collection step of collecting the fine dust, which has been collected in the dust collection step, and the small particles;
• a second magnetic separation step of removing a magnetic particle from an aggregate of the fine dust and the small particles;
• and
• a second classification step of classifying the aggregate into at least two or more types of particles,
• wherein:
• the first crusher is a biaxial crusher,
• the second crusher is a hammer mill,
• time after rough crushing of the scrap material with the first crusher until the scrap material is introduced into the second crusher is two minutes or longer, and
• time from when the scrap material is introduced into the first crusher until when the titanium cobbles are obtained is 40 minutes or shorter.

A method of producing titanium cobbles for use for at least one of a titanium ingot raw material, a superalloy, an additive material for an aluminum alloy, or an additive material for steel, the titanium cobbles being titanium-containing particles, each containing 50% by mass or more of metal titanium, and having a maximum size of 50 mm or smaller and an aspect ratio of 5 or lower, the aspect ratio being obtained by dividing the maximum size by a minimum size, the method comprising:

• a preparation step of preparing a scrap material containing 50% by mass or more of metal titanium;
• a first crushing step of roughly crushing the scrap material using a first crusher;
• a second crushing step of crushing the scrap material, which has been roughly crushed in the first crushing step, using a second crusher;
• a dust collection step of collecting fine dust of the scrap material generated in the second crushing step;
• a first classification step of classifying products obtained by crushing the scrap material, which have been generated in the second crushing step, into medium particles with particle sizes of 3 mm or larger and 50 mm or smaller, large particles with particle sizes larger than 50 mm, and small particles with particle sizes smaller than 3 mm;
• a first magnetic separation step of removing a magnetic particle from the medium particles;
• a return step for returning the large particles to the second crushing step;
• a collection step of collecting the fine dust, which has been collected in the dust collection step, and the small particles;
• a second magnetic separation step of removing a magnetic particle from an aggregate of the fine dust and the small particles;
• and
• a second classification step of classifying the aggregate into at least two or more types of particles,
• wherein:
• time after rough crushing of the scrap material with the first crusher until the scrap material is introduced into the second crusher is two minutes or longer, and
• time from when the scrap material is introduced into the first crusher until when the titanium cobbles are obtained is 40 minutes or shorter.