NOV TDS-1000 Main Shaft – Specification

1. Identification 

• OEM: National Oilwell Varco (NOV)
• Equipment: Top Drive System (TDS-1000)
• Component: Main Shaft (Spindle)
• Part Number: 10378775-001
• Description (OEM):
  • Main Shaft Machining
  • Includes Landing Collar Groove

2. Physical Dimensions (From Label)

• Maximum Outside Diameter: 9 in
• Overall Length: 96.47 in (~8.04 ft / 2.45 m)
• Design Feature:
  • Machined landing collar groove (for elevator/load interface)

3. Functional Role

The main shaft is the primary torque-transmitting spindle in the TDS:

• Transfers torque from gearbox/motor → drill string
• Supports:
  • Drill string weight
  • Rotational loads
  • Hydraulic flow path (through bore)
• Interfaces with:
  • IBOP (upper/lower)
  • Saver sub
  • Pipe connection

4. System Performance Context (TDS-1000)

This shaft operates within the following system limits:

• Hoisting Capacity: ~1,000 tons
• Motor Power: 1 × 1,150 HP AC motor
• Max Continuous Torque:
  • 62,250 ft-lb (84,399 Nm)
• Max Speed: ~270 RPM

👉 The shaft must be designed to handle full system torque + axial load simultaneously.