Overhaul or modification of underground drilling machines refers to changes made to improve the performance, efficiency or features of an existing machine. These revisions may be aimed at increasing the power, drilling speed, precision, maneuverability or other features of the machines.

Revisions are usually made by companies that manufacture or sell the machines or by specialized service providers. Overhaul of machines can often include changes such as:

  1. Strengthening: Increasing power through measures such as increasing the engine power of the machine or improving hydraulic systems.
  2. Precision and accuracy: Improving sensors or control systems to make the machine more precise.
  3. Drilling speed: Optimizing mechanical or hydraulic systems to speed up the drilling process.
  4. Manuver ability: Design or component changes to make the machine more easily portable or maneuverable.
  5. Automation: Adding or improving automation systems on the machine.

Revision of underground drilling machines may aim to make the machines work more efficiently, speed up work processes or provide cost savings. However, such overhauls are usually specialist work and are usually carried out by the manufacturer or authorized service providers.

I do not have specific information about any underground drilling machine revisions because there are many different machines and revision options in this field. Before carrying out overhauls or modifications, it is important to contact the companies or authorized service providers that manufacture or sell the relevant machines and request their advice or services