P540

1. CHEMICAL COMPOSITION

„P540“ is a special nonmagnetic, austenitic Mn-Cr-N-steel with a nitrogen content of ≤ 2%.

C Mn Cr Mo N Ni
max. 0,05 19,00 - 21,00 17,00 - 19,50 0,30 - 0,80 min. 0,50 0,80 - 2,00

 

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“ 120 ksi 830 N/mm²
  OD 9 1/2“ and larger 110 ksi 760 N/mm²
Tensile Strength (min.):   130 ksi 900 N/mm²
Elongation (min.):   20% 20%
Reduction of area (min.):   50% 50%
Impact energy (min.):   90 ft.lb 122 J
Endurance Strength / N=10⁵ (min.):   ± 65 ksi ± 455 N/mm²
Hardness Brinell: (min.):   285-400 HB 285-400 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- and nitrogen content 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.