How to prevent a kelly bar from breaking during construction?

Preventing a Kelly bar from breaking during construction involves a combination of proper usage, maintenance, and adherence to operational guidelines.
Here are some key steps to help ensure the longevity and proper functioning of a Kelly bar:

Proper Selection and Setup

• Choose the Right Kelly Bar: Ensure the Kelly bar is appropriate for the specific drilling conditions, including soil type and depth requirements. Before buying a kelly bar, please provide projects detailed information you have to our sales and our sales and engineer will prepare proper solution to match your projects.
• Correct Installation: Make sure the Kelly bar is correctly installed on the drilling rig. Improper installation can lead to excessive stress and eventual failure.
  1)Align the Kelly Bar: Position the Kelly bar in alignment with the Kelly drive adapter of the drilling rig. Ensure the central axis of the Kelly bar and the rig are aligned.
  2)Secure Attachment: Attach the Kelly bar to the Kelly drive adapter using the appropriate pins, bolts, or locking mechanisms specified by the manufacturer. Double-check that all securing devices are properly engaged and tightened.
  3)Follow Manufacturer's Instructions: Adhere strictly to the installation instructions provided by the manufacturer. These instructions will detail the specific steps and tools required for proper installation.
  4)Check for Free Movement: After installation, ensure the Kelly bar can move freely within the Kelly drive and extension sections. There should be no excessive play or binding.
  5)Test Rotation: Slowly rotate the Kelly bar to ensure smooth operation. Listen for any unusual noises or vibrations that could indicate improper installation or alignment issues.
  6)Check Locking Mechanisms: Verify that all locking mechanisms are properly engaged and secure. This includes any retaining pins, clips, or bolts.
  7)Visual Inspection: Conduct a thorough visual inspection to ensure that there are no visible gaps or misalignments between the Kelly bar and the rig.
  8)Torque Check: Use a torque wrench to ensure that all bolts and fasteners are tightened to the manufacturer's recommended torque settings.
  9)Operational Test: Perform a short operational test under controlled conditions to verify that the Kelly bar is functioning correctly and safely. Monitor for any signs of stress or misalignment during this test.

Operational Best Practices

• Avoid Overloading: Do not exceed the maximum torque and weight limits specified by the manufacturer. Overloading can cause structural damage.
• Smooth Operation: Avoid sudden starts and stops, and operate the rig smoothly to reduce stress on the Kelly bar.
• Monitor Rotation Speed: Maintain an appropriate rotation speed. Too high a speed can cause excessive wear and too low a speed can cause stalling and jerky movements.
• Proper Downforce: Apply the correct amount of downforce to the drill. Too much downforce can bend or break the Kelly bar.

If the kelly bar broken, how to repair it?

• Tube joint
  Disconnect all the pipe bodies. Remove the pipe from the main machine and place it on the ground pulley frame for leveling. Cut off the pipe body at the broken section, and weld and polish parallel alignment pairs of pipe bodies of the same material, diameter and wall thickness of the required length. Finally weld the key strip.
• Welding specifications
  The butt joint will be sanded with a grinding wheel with a 30-degree break, as narrow as possible, to sand the mouth. Then preheat 200 ℃, shall not exceed 250 ℃. Steel pipe diameter greater than 245 mm with J506, J507, or equivalent performance wire welding; diameter 245 mm below the drill pipe with 80 kg of low-hydrogen, low-sulfur resistance to cold cracking, heat cracking welding material. Welding according to the recommended specifications for the use of welding consumables, but welding should try to use a small weld multi-layer welding. After welding to polish the whole. Do not weld leakage. After welding attention to insulation. Weld leakage of the weld tumor should find ways to remove.

Maintenance and Inspection

• Regular Inspections: Conduct regular inspections for signs of wear, cracks, or other damage. Pay special attention to the joints and welds.
• Lubrication: Ensure all moving parts are adequately lubricated to reduce friction and wear.
• Immediate Repairs: Address any signs of wear or damage immediately to prevent minor issues from becoming major problems.
• Replace Worn Parts: Replace any components that show significant wear and tear, especially the teeth and sections that bear the most stress.

Training and Supervision

• Operator Training: Ensure that operators are well-trained in the use of the specific drilling rig and Kelly bar. They should understand the importance of following operational guidelines and best practices.
• Supervision: Provide adequate supervision, especially for less experienced operators, to ensure that the equipment is used correctly.

Environmental Considerations

• Adapt to Soil Conditions: Adjust operational techniques based on soil conditions. Hard or rocky soils may require different handling compared to softer soils.
• Weather Conditions: Be cautious when operating in extreme weather conditions, which can affect the soil and the behavior of the equipment.