NACE INTERNATIONAL STANDARD MR0175-98

 

Sulfide stress cracking resistant metallic materials for oilfield equipment

 

1.         Scope

1.1.            This standard presents metallic material requirements for sulfide stress cracking (SSC) for petroleum production, drilling, gathering and flowing equipments, and field processing facilities to be used in hydrogen sulfide (H2S) bearing hydrocarbon service.

1.2.            This standard applies to all components of equipment exposed to sour environments. Where failure by SSC would.

            1.2.1.Prevent the equipment from being restored to an operating condition

                      while continuing to contain pressure.

1.2.2.Compromise the integrity of the pressure containment system, and/or

1.2.3.prevent the basic function of the equipment from occurring.

1.3.            SSC is affected by factor such as

1.3.1.Material chemical composition, strength, heat treatment and microstructure.

1.3.2.Hydrogen ion concentration (PH) of the environment.

1.3.3.H2S concentration and total pressure.

1.3.4.Total tensile stress (applied plus residual ).

1.3.5.Temperature and

1.3.6.Time

The user has to determine whether or not the environmental conditions are such that MR0175 applies.

2.         SSC may be controlled by.

2.1.Using the materials and process prescribed in NACE standard

2.2.Controlling the environment or

2.3.Isolating the components from sour environment

3.                  Test levels I to VII depending on environmental condition.

4.         Ferrous metals

The Susceptibility to SSC of most ferrous metals can be strongly effected by heat treatment cold work or both.

Carbon & low alloy steels

All carbon & low alloy steels are acceptable at 22 HRC maximum hardness provided they (a) contain less than 1% nickel (2) will meet the fabrication process & in process heat treatment as specified in the standard (3) are used in one of the following heat treated conditions.

 

a)      Hot rolled (carbon steels only)

b)      Annealed

c)      Normalized

d)      Normalized & tempered

e)      Normalized austenitized ; quenched & tempered

f)        Anstenitized quenched & tempered.

 

            Fabrication process

a)       The metal must be thermally stress relieved following any cold deforming by rolling, cold forging or any other manufacturing process that results in a permanent outer fiber deformation greater than 5% min S.R. temperature 595oC

        This requirement does not apply to pipe grades as listed herein or cold  work imparted by

        pressure test up accordingly to applicable code.

 

 

 

 

Acceptable API and ASTM specifications for Tubular goods

 

For all Temperature A

 

Operating Temperatures B

For 65OC (150 OF) or Grater

For 80OC (175 OF) or Grater

 

For ≥107OC (≥225OF)

Tubing and casing

API Spec 5CT Grs.H-40C , J-55 , K-55 , C-75 (types 1,2,3) and L-80 (type 1) 

Tubing and Casing

Api spec 5CT Gr N-80

(Q & T) & Gr. C-95

Tubing and Casing

API Spec 5CT Grs. H-40, N-80 P-105 & P-110

 

 

 

API Spec 5CT Gr.

Pipe D,E

API spec 5L Grs A & B and Grs X-42 through X-65

ASTM A53

A106 Gr. A,B,C

A333 Gr 1 & 6

A524 Gr 1 & 2

A381 Cl 1 Y35-Y65

Proprietary Q & T Grs with 110 Ksi  or

Proprietary Q & T Grs to 140 ksi maximum Y.S

 

Note Pipe shall have a maximum hardness of 22 HRC

b)       Welding procedure to be followed as per AWS/API/ASME

c)        Hardness to be controlled on weld & HAZ.

d)       Welding rods, electrodes, fluxes, filler metals with more than 12 nickel shall not be used.

e)        Identification stamping using low stress (dot, vibratory and round V ) stamps is acceptable. Sharp V stamping is not permitted in low stress areas unless subsequently stress relieved at minimum 595oC.

f)         Cold deformation by controlled shot peening is permitted when applied to base metals to base metals and when limited to the use of maximum shot size of 2mm.

      and a maximum of 10C. Almen intensity. The process shall be controlled as per MIL-S- 13165