Kelly
Product features: Made from AISI 4145H-4145H Mod. alloy bars that are quenched and tempered full length, which up to 46 feet long. A hardness range of 285 to 341 BHN and a minimum impact value of 40ft-lbs are maintained one inch below the surface at room temperature. All ends and center drive sections trepanned to provide true bores. They are drifted to API specifications, and all connections are machined.

It is intergral, not weld

Material: AISI 4145H-4145H Mod.

Standard: According to API Spec standard.

Type: Square kelly
　　　Hexagonal kelly

Output: 50~100 pcs Ton per month.