1. CHEMICAL COMPOSITION

„P650 HS“ is a special nonmagnetic, austenitic Mn-Cr-Mo-N-steel with a high pitting corrosion resistance , specifically developed for oilfield applications.

C	Mn	Cr	Mo	N	Ni
max. 0,06	19,50 - 20,50	18,00 - 19,00	1,70 - 2,00	0,55 - 0,65	3,00 - 4,50

 

2. MECHANICAL PROPERTIES

Following mechanical properties (tested at room temperature) are achieved by a special cold-working process over the full length of the collar:

TEXT	OD	KSI	N/MM
Yield Strength (min.) 0,2%-offset method:	OD up to 9 1/4“	180 ksi	1242 N/mm²
	OD 9 1/2“ and larger	170 ksi	1173 N/mm²
Tensile Strength (min.):		185 ksi	1277 N/mm²
Elongation (min.):		12%	12%
Reduction of area (min.):		50%	50%
Impact energy (min.):		80 ft.lb	110 J
Endurance Strength / N=10⁵ (min.):		80 ksi	550 N/mm²
Hardness Brinell: (min.):		330-450 HB	330-450 HB

 

3. MAGNETIC PROPERTIES

Relative permeability: ≤ 1,005.

 

4. CORROSION RESISTANCE

• Transgranular SCC: Prevented by special surface treatments (Hammer peening, roller burnishing, shot peening).

• Intergranular SCC: The occurrence of material sensitization is prevented by quenching after warmforging. Each collar is tested according to ASTM A 262, Pract.A and E, last edition.

• Pitting Corrosion: Due to a high chromium-, molybdenum- and nitrogen contents a high resistance to pitting corrosion is given.

 

5. NON-DESTRUCTIVE TESTING

• Magnetic inspection: Drill collars are 100% tested by a proprietary probe-testing process using a Förster Magnetomat 1.782. (“Hot Spot“-test). Magnetic permeability of each collar is certified with the printout of probe-testing.

• Ultrasonic inspection: Each collar is ultrasonically inspected over 100% of the volume according to ASTM E 114, last edition as a minimum level.