121131 Alloy Steel Main Shaft for Nov Varco TDS11SA Top Drive System

1, Daily maintenance

Cleaning and lubrication

Clean the mud and oil stains on the surface of the Main shaft after daily homework, and use non-woven fabric to wipe key parts (such as taper joints) to avoid chemical corrosion.

Supplement lubricating grease (such as lithium based grease) according to the manufacturer's requirements. The oil injection cycle for the main shaft bearings should not exceed 200 hours, and the oil injection amount should be precisely controlled to avoid contamination.

Fastener inspection

Regularly check the pre tightening force of the main shaft connecting bolts (such as lifting ring screws and coupling bolts), and the torque should comply with the technical manual standards (such as DQ70BS top drive requiring bolt torque ≥ 1200N · m).

2, Regular maintenance

Bearing and seal testing

Disassemble and inspect the wear of the Main shaft bearing every 500 hours, measure the radial clearance with a micrometer, and replace it if it exceeds 0.05mm.

Seals (such as O-rings) should be replaced quarterly, and priority should be given to using fluororubber material to resist hydrogen sulfide corrosion.

Conical interface maintenance

Check the wear of the Main shaft cone mouth every month. When the contact rate of the tool holder is below 75%, it needs to be ground and repaired to avoid excessive jumping caused by the "horn mouth".

3, Fault prevention and handling

Vibration and temperature monitoring

Install vibration sensors to monitor abnormal Main shaft vibration in real-time (threshold ≤ 2.5mm/s). If the temperature rise exceeds 60 ºC, the machine should be stopped to troubleshoot lubrication or bearing issues.

Emergency measures

When the drill suddenly gets stuck, immediately activate the IBOP blowout preventer, cut off the power, and manually turn the disc to release torque to avoid overloading and deformation of the Main shaft.

4, Special maintenance

Electric drive Main shaft: Verify the coaxiality of the motor and Main shaft every six months (deviation ≤ 0.1mm), and clean the cooling channel of the frequency converter.

Hydraulic Main shaft: Regularly replace the hydraulic oil filter element (with a cycle of 200 hours), and the oil cleanliness should reach NAS level 7.