• Product Specifications


    API Connections
    Grant Prideco drill collars are manufactured in 30-ft and 31-ft lengths. All API connections comply with dimensional requirements specified in API Spec. 7 and guidelines presented in API RP7G. Common sizes and styles are summarized on the next page. In addition, other connections, such as OH, FH, PAC, WO, SLH9O, SH, and H90, are available to meet specific needs.



    Cold Rolling 
    Drill collar thread roots as well as elevator and slip recess upper radii are cold-rolled. Cold rolling creates a compressive stress condition that increases fatigue life by minimizing crack initiation.

    Phosphate Coating
    All connections are phosphate-coated to improve resistance to galling.

    Stress Relief Features
    API pin stress relief groove and API boreback box decrease the frequency of fatigue failures. These features increase connection flexibility and reduce high-stress concentrations that normally occur adjacent to the end of engaged threads. Stress relief features are machined in compliance with API Spec. 7. 

    As indicated in API Spec. 7, connections NC23, NC26 (2 3/8 IF) and NC31 (2 7/8 IF) do not have sufficient metal to accommodate stress relief features.