• Care and Maintenance

    Description

    Initial Make-up
    Even though quality connections are heavily coated with phosphate, thread damage is not always prevented. A generous and thorough application of high-quality thread dope (40 to 60% by weight metallic zinc minimum) will help minimize galling.

    New connections should be "walked in" with chain tongs. Always use the recommended make-up torque for the thread design. Exercise care to maintain calibrated torque measuring and indicating gauges for future use. After initial make-up, break-out the connection, clean and inspect the threads, faces and shoulders. Repair any minor damage. Re-lubricate and re-torque the connection.

    Repeat break-out and make-up a third time before going in the hole. Monitor break-out torque. It should be the same or less than the make-up torque. High break-out torque is an indication of problems and the connection should be inspected for damage.

    Maintenance
    Use thread protectors on both connections when handling drill collars. Rotate breaks on each trip. Clean and inspect the individual connections.

    Qualified personnel should periodically conduct a magnetic particle/black light inspection. Collars that are left idle or put in storage should be cleaned, inspected, repaired, and rust-proofed, as necessary, before installing thread protectors. 

    Bending Strength Ratios
    Sizes less than 6” should have a BSR of 2.25:1 to 2.75:1. Conditions that require high rpm and small collars compared to the hole size, use 2.25:1 to 3.00:1. If the rpm is kept low and the collars are closer to the hole size, use 2.25:1 to 3.20:1. In corrosive environments, use 2.50:1 to 3.00:1.