Method for depositing coatings on the interior surfaces of tubular structures

A method for coating an interior surface of a ferromagnetic tubular structure, said method comprising:

• positioning a ferromagnetic tubular structure and a magnetic field source in the vicinity of one another;
• operating the magnetic field source to induce a magnetic field of a given magnitude within the tubular structure;
• applying a bias at a given voltage to the tubular structure;
• and
• exposing the interior surface to a gaseous precursor material under conditions effective to convert a quantity of the gaseous precursor material to ionized gaseous precursor material, the given magnitude and the given voltage being effective to deposit the ionized gaseous precursor material onto the interior surface and to convert the ionized gaseous precursor material to a protective coating along a length of the interior surface.

A method for substantially uniformly coating an interior surface of a ferromagnetic tubular structure, said method comprising:

• positioning a ferromagnetic tubular structure having a high aspect ratio relative to a magnetic field source;
• inducing a magnetic field having a given magnitude within the tubular structure by operating the magnetic field source;
• applying a bias at a given voltage to the tubular structure;
• and
• exposing the interior surface to a gaseous precursor material under conditions effective to convert a quantity of the gaseous precursor material to ionized gaseous precursor material, the given magnitude and the given voltage being effective to deposit the ionized gaseous precursor material onto the interior surface and to convert the ionized gaseous precursor material to a substantially uniform protective coating along a length of the interior surface.