a Nine stage process

API 4G Category IV Mast & Substructure Refurbishment Process

• 1

  Visual Inspection & Complete Disassembly (Rig Site)

  Thoroughly inspect the mast and substructure at the rig site to identify any visible damage or wear, including potential weld defects. Then, disassemble the mast and substructure into manageable sections.

• 2

  Strip Components (Rig Site)

  Remove all components (tong counterweights, lights, walkways, etc.) at the rig site.

• 3

  Transport to Workshop

  Move the disassembled sections and stripped components to the refurbishment workshop.

• 4

  Sandblasting

  Clean the entire structure using sandblasting to remove old paint, rust, and debris.

• 5

  NDT of Critical Welds

  Conduct non-destructive testing on critical welds to detect any internal flaws after the surface has been thoroughly cleaned.

• 6

  Dimensional Inspection

  Measure and verify the dimensions of critical components such as sheaves, shafts, pins, bearings, and other wear-prone parts to ensure they meet API 4G specifications. Replace or repair any components that are out of tolerance.

• 7

  Repair of Welds 

  Perform any necessary repairs or reinforcements to welds based on NDT findings and engineering assessment.

• 8

  Painting

  Apply a protective coating of paint to prevent corrosion.

• 9

  Reassembly & Final Inspection

  Reassemble the structure and conduct a final inspection to ensure compliance with API 4G standards.