Drill Collar is the basic component in the BHAwhich provides weight on the bit for drilling andkeeps the drill string in tension.
TIANHE Drill Collar is manufactured fromAISI 4145H modified quenched and temperedsteel and is heat treated along its entirelength for uniform toughness and durabilityStrict metallurgical tests are performed perspecifications to ensure that the heat treatmentproduces consistent and maximum hardnessthrough the depth of the bar.
Connections are phosphate coated afternachining to protect the threads fromcorrosive elements and to prevent gallingupon initial make up:
Thread roots are cold rolled on API and H-90connections:
Pressed steel thread protectors are suppliedfor all drill collar that are equipped withstandard connections
Features and Benefits
A hardness range of 285 to 341 BH Nand a Charpy impact value of 40 lbs/ft areguaranteed for evenly distributed 16 points inany cross sections at room temperature!
When ordering please specify:
Drill collar OD and ID:
Overall length;Connections required (size and type)!Special features desired, for exampleSlick or Spiral;
Stress Relief Features,
Slip and/or Elevator Recess;Hardbanding;
Specifications - Drill Collar
Spiral Grooving
In order to reduce differential pressure sticking, the surface of drill collars can be sp
note 1-Loss of weight is approximatively 4%, compared to slick drill collars. note 2-Length of spiraled section allows reconditionning of connection
Stress Relief Groove & Bore BackBox
Stress relief grooves improve bending strength otpin and box connections and, therefore, durability.Stress relief grooves for box and pin are defined byAPI.
Bore back box is a gradual reduction of internadiameter by gradually increasing material crosssectional area at critical section. This will ultimateldrastically reduce stress concentration during staticdynamic loading and prevents box connectionsfrom failure.
Hardbanding
We provide several hardbandina materials forcustomer's choice: Arnco-100XT. Arnco-300xTTCS-8000;
Slip and Elevator Recess
Slip and elevator recesses improve downholehandling efficiency and safety. Slip and elevatorrecesses are machined in accordance with API 7-1
Recommended Hardbanding Location
Drill collars with slip and elevator recesses (ZIP4" long wear pad above elevator recess
1" long wear pad above slip recess.10" long wear pad under slip recess
Drill collars with slip recess:
10" long wear pad under slip recess4" long wear pad above slip recess
Drill collars without slip and elevator recesses:10" long wear pad at 30" from pin shoulder
Tianhe Oil Group Huifeng Petroleum Equipment Co., Ltd is a modernized medium-scale enterprise specialized in production of oil and gas tools.
As an API-Certified established manufacturer and supplier of a comprehensive range of downhole equipment with related accessories, we are committed to providing the highest Quality products for the Petroleum and natural gas industry since 1973.
Tianhe Oil Group strongly believes and promotes Total Quality Management, implement the ISO quality management system and HSE management system and API Standard, which has been deeply implanted into every person's thought and carried out into every aspect of work.
Our manufacturing facilities are well equipped with four automated induction heat treatment lines and dozens of other types of heat treatment ovens and well furnaces to ensure full coverage of heat treatment requirements by different products to achieve the required mechanical properties.
In order to ensure the quality consistency and interchangeability of high precision components, Tianhe has introduced WFL 5-axis Linkage Turning & Milling Machining Center from Austria, Mazak's turn milling machining center from Japan and the Haas vertical machining center from USA. These processes are facilitated with precise quality inspection equipment such as the Brunker OES Metal Analyzers from Germany, Ultrasonic and Magnetic Powder Flaw Detector and high precision Hexagon Three Coordinate Measuring Machine and Farco Portable Three Coordinate Measuring Machine.
So far, Tianhe Oil Group has established strong business relationships with over 200 international oil & gas companies in supporting the top 50 oil producing countries.
We take pride in delivering superior performances and reliability. Our objective is to exceed your expectations, improve your economics and be an integral part of your strategies.
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