API Standard Non-magnetic Drill Collar (NMDC)

Product Details

>>Introduction

A non-magnetic drill collar is a specialized type of drill collar made from non-magnetic materials, typically non-magnetic alloys or composites. It is used in drilling operations where magnetic interference or detection is a concern.

In some drilling scenarios, such as when drilling near magnetic materials or in areas with significant magnetic anomalies, the presence of magnetic components, like standard steel drill collars, can interfere with downhole measurement tools, such as magnetic resonance imaging (MRI) logging tools or magnetic survey equipment. Magnetic interference can affect the accuracy and reliability of these tools, leading to potentially inaccurate data or measurements.

Non-magnetic drill collars are designed to minimize or eliminate the magnetic field generated by the drill string. They are typically made using non-magnetic alloys such as aluminum, titanium, or specific grades of stainless steel. These materials have low magnetic permeability, meaning they have minimal or no magnetic influence on nearby measurement instruments.

By using non-magnetic drill collars, drilling operators can reduce or eliminate interference with downhole measurement tools, allowing for more accurate data acquisition and interpretation. This is particularly important in situations where precise measurements are essential for geological evaluation, reservoir characterization, or wellbore positioning.

Orchid Energy Non Magnetic Drill Collar (NMDC) are made from low-carbon stainless steel as API specification and implementation of SY/T5144 standard, which can be cold thread rolling, machine special double shoulder thread and do as other specifications request. Non Magnetic Drill Collar are as a housing for MWD tools and also could provide weight for drill string.

>>Parameter Table

Connection	OD		ID		Length (mm)	Bevel Diameter (mm)	Weight (lb/ft)	Bending Strength Ratio
	(in)	(mm)	(in)	(mm)
NC23-31	3-1/8	79.4	1-1/4	31.8	9150	76.2	22	2.57:1
NC26-35	3-1/2	88.9	1-1/2	38.1	9150	82.9	27	2.42:1
NC31-41	4-1/8	104.8	2	50.8	9150	100.4	35	2.43:1
NC35-47	4-3/4	120.7	2	50.8	9150	114.7	47	2.58:1
NC38-50	5	127	2-1/4	57.2	9150	121.0	53	2.38:1
NC44-60	6	152.4	2-1/4	57.2	9150 or 9450	144.5	83	2.49:1
NC44-60	6	152.4	2-13/16	71.4	9150 or 9450	144.5	75	2.84:1
NC44-62	6-1/4	158.8	2-1/4	57.2	9150 or 9450	149.2	91	2.91:1
NC46-62	6-1/4	158.8	2-13/16	71.4	9150 or 9450	150.0	83	2.63:1
NC46-65	6-1/2	165.1	2-1/4	57.2	9150 or 9450	154.8	99	2.76:1
NC46-65	6-1/2	165.1	2-13/16	71.4	9150 or 9450	154.8	91	3.05:1
NC46-67	6-3/4	171.4	2-1/4	57.2	9150 or 9450	159.5	108	3.18:1
NC50-67	6-3/4	171.4	2-13/16	71.4	9150 or 9450	159.5	108	2.37:1
NC50-70	7	177.8	2-1/4	57.2	9150 or 9450	164.7	117	2.54:1
NC50-70	7	177.8	2-13/16	71.4	9150 or 9450	164.7	110	2.73:1
NC50-72	7-1/4	184.2	2-13/16	71.4	9150 or 9450	169.5	119	3.12:1
NC56-77	7-3/4	196.8	2-13/16	71.4	9150 or 9450	185.3	139	2.70:1
NC56-80	8	203.2	2-13/16	71.4	9150 or 9450	190.1	150	3.02:1
6 5/8REG	8-1/4	209.6	2-13/16	71.4	9150 or 9450	195.7	160	2.93:1
NC61-90	9	228.6	2-13/16	71.4	9150 or 9450	212.7	195	3.17:1
7 5/8REG	9-1/2	241.3	3	76.2	9150 or 9450	223.8	216	2.81:1
NC70-97	9-3/4	247.6	3	76.2	9150 or 9450	232.6	229	2.57:1
NC70-100	10	254	3	76.2	9150 or 9450	237.3	243	2.81:1
8 5/8REG	11	279.4	3	76.2	9150 or 9450	266.7	299	2.84:1

Tolerance Size of Non-Magnetic Drill Collar (NMDC)

OD Range		OD	ID	Length	Shoulder chamfer diameter-DF
(mm)	(in)
≤88.9	≤3 1/2	+1.2 0	+1.6 0	+152.4	±0.4
＞88.9~114.3	＞3 1/2~4 1/2	+1.6 0
＞114.3~139.7	＞4 1/2~5 1/2	+2.0 0
＞139.7~165.1	＞5 1/2~6 1/2	+3.2 0
＞165.1~215.9	＞6 1/2~8 1/2	+4.0 0
＞215.9~241.3	＞8 1/2~9 1/2	+4.8 0
＞241.3	＞9 1/2	+6.4 0

Mechanical Property of Non-Magnetic Drill Collar (NMDC)

Steel Grade	OD Range	Yield Strength Rt		Tensile Strength Rm		Elongation	Impact Value	Hardness Brinell
	in	Mpa	ksi	Mpa	ksi	A(%)	Akv/L	(HB)
NM530	3 1/8 - 6 7/8	≥827	≥120	≥827	≥120	≥25	≥150	285-360
	7 - 9 1/2	≥758	≥110
NM550	3 1/8-6 7/8	≥965	≥140	≥1034	≥150	≥25	≥150	285-360
	7- 9 1/2	≥827	≥120
NM650	3 1/8-6 7/8	≥965	≥140	≥1034	≥150	≥20	≥90	330-400

Test and Inspection carried out on each bar: Chemical Composition, Tensile Test, Impact Test, Hardness Test, Metallographic Test, Corrosion Test, Ultrasonic Test over the whole length of the bar, Relative magnetic permeability Test, Hot spot Test, Dimensional Inspection.