Project Description
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.
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.
Quality Standard: API 7 Specification for Rotary Drill Stem Elements, API RP7G
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.
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
Protection:
- Standard Pressed Steel Thread Protectors.
- Cast Steel Lifting Bail Thread Protectors upon request.
Mill Test Certificates:
- 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.
ORDERING INSTRUCTIONS:
When ordering or requesting quotations on drill collars, please specify:
1. Drill collar OD
2. Drill collar ID
3. Overall length
4. Connections required (size and type)
5. Indicate preference for pressed or cast steel thread protectors
6. Special features desired, for example:
- Slick or Spiral
- Stress Relief Features
- Slip and/or Elevator Recess
- Hardbanding
We are committed to integrate steel resources in china and serve the global steel market. Our company has more than 15 years of experience in steel researching, production, managing and sales. And our team mostly are based on and worked in national famous steel enterprise before. In the aspect of resources and information, we have established cooperative relationship with nearly hundred enterprises, either state-owned or private owned in China.
What’s more, we have built long, deep and close business relationship with dozens of steel company, Sharing and holding equities with several steel enterprises. Because of the close cooperation with steel companies and our pioneering spirit, which can ensure us stay at the top competition, and ensure our customers get what they really want. We provide preffesional one-stop service to the Contractors of follows project:
- Oil and Gas Pipeline Construction
- Onshore and Offshore
- Boiler Manufacturers
- Oil Refining Equipment
- Petroleum and Chemical Plant Construction
- Fire Protection
- Heating & Air Conditioning
Our ability to purchase materials directly from leading mills at the best possible price will give you the competitive edge. This coupled with a skilled workforce dedicated to embracing the demands of the markets we serve. Just give us a call +86-731-89903933.
