Rotary Kelly

Kelly is main driver of the whole drill string. It transmits torsional energy from the
rotary table through the drill string to the bit at the bottom of the hole. TIANHE
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, thus
straightness inspections are carried out before, during and after each machining
operation. The flats are precision-milled to API specifications. All milling processes
are performed on specially designed rigid Kelly mills to ensure tight tolerances and
high quality drive sections. Each TIANHE Kelly is furnished with a pressed steel
thread protectors.

Features and Benefits
●Manufactured from AISI 4145H-modified, fully heat-treated alloy steel with a
Brinell hardness range of 285-341BHn and a minimum average Charpy impact
value of 40 ft-lbs;
●Ends and drive sections, IDs and connections machined and inspected to API
specifications;
●Ultrasonic inspection is performed on all sections;
●Shipped in a protective steel-cased scabbard;
 

When ordering please specify:
●Kelly type (square or hexagonal);
●nominal size and overall length;
●Upper and lower connections.