Introductions:
Casing and tubing for Sour Oil and Gas Service must have a good anti-SSCC (sulfide stress corrosion and cracking) performance in the environment where hydrogen sulfide corrosion exists. After an indepth study, we has successfully developed tubular goods of the Cr-Mo series for this purpose with good hardenability and tempering stability that when tempering takes places at certain temperatures uniform and fine sorbite structures can be obtained. Their mechanical properties can meet fully the requirements of corresponding grades and their anti-SSC performance is excellent by regulating the chemical composition and adopting different heat treatment procedures
Standard:
API 5CT Specification for Oil Tubing
Grade:
Mechanical Properties:
Tensile Strength (Ksi): 517min
Characteristics:
1. Materials: The chemical compositions have been carefully determined to provide resistance to sulfide stress corrosion as well as to insure complete through wall hardening.
2.Heat Treatment: Quenching and Tempering are conducted under rigid temperature control to assure homogeneous physical properties and microstructures.
3.Micro Structure: These grades exhibit fully tempered martensite which is considered to be the most desirable for resistance to sulfide stress corrosion cracking.
5. Sulfide Stress Cracking (SSC) Performance: Whole grades are designed for 85% or 90% SMYS in NACE condition. Excellent SSC resistance has been achieved through rigorous, chemical composition, heat treatment, microstructure, tensile properties, hardness and so on.
Pipe inspection:
A full length non destructive inspection is performed in accordance with API 5CT for external and internal, longitudinal and transverse defects with a standard notch depth equal to 5% of the specified wall thickness.
