Method and apparatus for a monodiameter wellbore, monodiameter casing, monobore, and/or monowell

A method for drilling a monodiameter borehole, the method comprising:

• drilling a first portion of the borehole with a drilling assembly having a bit and downhole motor;
• raising the drilling assembly in the first borehole portion;
• introducing chemical casing into the initial borehole;
• allowing the chemical casing to set up and form a chemical casing on the borehole wall;
• drilling through the chemical casing in the initial borehole;
• installing a casing string in the first borehole;
• drilling a second portion of the borehole with a drilling assembly;
• raising the drilling assembly in the second borehole portion;
• introducing chemical casing into the second borehole;
• allowing the chemical casing to set up and form a chemical casing on the borehole wall;
• drilling through the chemical casing in the second borehole;
• installing an expandable casing string in the second borehole;
• and
• repeating the above steps by drilling additional borehole portions and installing expandable casing until the borehole is drilled.

A method for drilling a monodiameter borehole, the method comprising:

• drilling one or more portions of a non-producing borehole with a drilling assembly having a bit and downhole motor;
• forming a chemical casing on the wall of the non-producing borehole wall;
• and then
• installing one or more strings of expandable casing in the non-producing borehole;
• drilling a producing borehole with a drilling assembly;
• and
• installing production tubing in the producing borehole.