Downhole machining of well completion equipment

A method of machining a workpiece in a subterranean wellbore, comprising the steps of:

• (a) providing a tubular member having a hollow axial bore therethrough and an opening at each end that comprises:
• (1) a first section comprising an outer tubular member having a hollow axial bore therethrough and having a inner surface and an outer surface, and
• (2) a second section comprising a second material, the second section forming at least one surface of the workpiece;
• (b) placing the workpiece in a subterranean wellbore that is surrounded by a geologic formation;
• and
• (c) machining the workpiece at least part of the second material from the inner surface of the inner tubular member in a predetermined pattern, thereby forming a locking profile in the inner surface of the inner tubular member.

A method of machining a workpiece in a subterranean wellbore, comprising the steps of:

• (a) providing a landing nipple that comprises:
• (1) a first section that comprises a first material, and
• (2) a second section that comprises a second material, the second section forming at least one surface of the workpiece;
• (b) placing the landing nipple in a subterranean wellbore that is surrounded by a geologic formation;
• and
• (c) machining the landing nipple to remove at least part of the second material in the second section, whereby at least one surface of the landing nipple is formed into a desired configuration.

A downhole assembly, comprising:

• a landing nipple located in a subterranean wellbore, the landing nipple comprising:
• (1) a first section that comprises a first material, and
• (2) a second section that comprises a second material, the second section forming at least one surface of the landing nipple;
• wherein the second material is more readily removed by machining than the first material.