rotary kelly

 ROTARY KELLY

Kelly is main driver of the whole drill string . It transmits torsional energy from therotary table through the drill string to the bit at the bottom of the hole . Kelly is a long square or hexagonal , precision machined heavy steel bar that is supported by the swivel through the rotary table and is connected to the first Joint of drill pipe in the drill string.  

Straightness of the kelly is very crucial in the manufacturing process , thusstraightness inspections are carried out before , during and after each machiningoperation . The flats are precision-milled to API specifications . All milling processesare performed on specially designed rigid Kelly mills to ensure tight tolerances andhigh quality drive sections . Each  Kelly is furnished witha pressed steelthread protectors.      

Features and Benefits

l Manufactured from ASI 4145h-modified , fully heat-treated alloy steel with aBrinell hardness range of 285-341BHN and a minimum average Charpy impactvalue of 40 ft-lbs;  

l Ends and drive sections , IDS and connections machined and inspected to APIspecifications; 

l Ultrasonic inspection is performed on all sections;

l Shipped in a protective steel-cased scabbard

When ordering please specify

l Kelly type ( square or hexagonal

l nominal size and overall length

l Upper and lower connections

Specifications-Rotary Kelly