Non-Magnetic Spiral Drill Collars 8.25inch 9.5inch

Spiral drill collars

These collars are machined with spiral grooves throughout their length to help minimize wall contact, which dramatically reduces the risk of sticking during operations.

Steel and Non-Mag drill collars

Our non-magnetic drilling collars are typically made slick, but can be spiral-machined as needed. These collars are often used in directional drilling applications to avoid interference.

Non-magnetic drill collars

 NMDCs are generally flush (non-spiral). They are manufactured from high-quality, corrosion-resistant, stainless steel. They are used while running the magnetic survey instruments to be located in a NMDC of sufficient length to allow the measurement of the earth's magnetic field without magnetic interference. Survey instruments are isolated from magnetic disturbance caused by other steel components in the BHA.

Drill Collars in Drilling Application

Drill collars play a vital role in drilling process. Due to the structural features, drill collars can provide weight for drilling purpose, which is drill collar’s one and foremost specialty. Gravity works on a number of drill collars to offer enough downward force needed to break rocks with the drill bit. 

Apart from providing weight on the bit (WOB), drill collars also work as a shock absorber to dampen the vibration and shaking when drilling takes place. In this way, the drilling process can be carried out in a much steadier state.

Thirdly, the presence of the drill collars allows the pipelines to stay in the tensile state, while guarantees the rigidity of the drill string under great compression. Thus, the drill efficiency and quality are greatly improved.

In addition to the above applications, drill collars can help to control the direction of the bottom hole assembly, avoiding the problem of hole deviation and enhancing the performance of drilling.

Non-magnetic Spiral Drill Collar 6.750” NC50

Non-magnetic Spiral Drill Collar 8.250” 6 5/8” Reg

Non-magnetic Spiral Drill Collar 9.500” 7 5/8” Reg

Drill Collar Classification

Drill collars can be simply put into three categories according to their structure and material, namely the slick drill collar, the spiral grooved drill collar and the non-magnetic drill collar.

The slick drill collar is normally a smooth thicked-wall tube, with a thickness in the range of 38 to 53, about 4 to 8 times of that of the drill pipes. It is machined into a uniform cylindrical shape and made up of plain alloy steel.

The non-magnetic drill collar is manufactured from the non-magnetic alloy steel. As the magnetic measuring instruments can sense the geomagnetic field when measuring the direction of the borehole, the instruments must be kept working in a non-magnetic environment. However, in drilling process, the magnetic rigs always affect the accuracy of the measuring instrument. Therefore, the utilization of a non-magnetic drill collar can ensure a more reliable measuring result.

The spiral grooved drill collar is also machined from plain alloy steel, but it is normally lighter by 4 to 6 percent than the slicker drill collar. This kind of drill collar is widely used nowadays because the special spiral design largely hold back of the possibility of sticking accidents by reducing the area of contact between the wall and the collar.

For more information please contact:

ROSCHEN INC.
ROSCHEN GROUP LIMITED
ROSCHEN HOLDINGS LIMITED

Skype: ROSCHEN.TOOL , ROSCHEN_GROUP

WeChat: +86-137 6419 5009 ; +86-135 8585 5390

WhatsApp: +86-137 6419 5009 ; +86-135 8585 5390

Email: roschen@roschen.com ; roschen@roschen.net

Website: http://www.roschen.com ; http://www.roschen.net