Features and Benefits:                                                                                                                                                  

• API Boreback Box Connection
• API stress relieve groove pin connection
• Cold Rolling Thread roots
• Phosphate coated connections
• A hardness range of 285 to 341 BHN and a Charpy impact value of 40 ft-lbs are guaranteed at evenly distributed 16 points in any sections at room temperature;
• Connections are completed(phosphate coated)to protect them from the elements after machining and to help prevent galling upon initial make-up;
• Thread roots are cold rolled on API and H-90 connections;
• Pressed steel thread protectors are supplied for all drill collar that are equipped with standard connections

Product Introduction:                                                                                 

Drill Collar are one of the parts of a drill’s string. Drill for the Collars is meant to provide weight for drilling purposes. Drill collar has bars of solid steel that are drilled from one end to the other to provide a passage for pumping the drilling fluids through the collar.

Product Application:                                                                                  
Drill collar are extra-heavy integral tools used to concentrate weight onto the drill bit so as to produce sufficient force for the drill bit to break rock efficiently while drilling. They are made of AISI 4145H modified steel and are connected between drill pipes and drill bits.
Size Range:                                                                                                

OD 3 1/8″ – 11 ″ 
Length: The standard drill collar length is 31′ 6″ . For outside diameters larger than 4″, slip or elevator recesses can be cut according to API-recommended practice RP7G. Connections are cut with standard API relief features, cold rolled and kemplated.
Mill Test Certification:                                                                              
Issued in accordance with API 7/7-1 and API RP7G specifications.
Third Party Inspection can be performed on request at buyer’s care and expense.

Product Pictures:                                                                                     

Company information: