The Springhouse Country Market and Restaurant has been a local icon for over 40 years. The commercial bakery floor had been covered for years with a commercial sheet vinyl that would fail in spots due to the infiltration of water and cleaning materials at the seams. This resulted in the need to repair the sheet material several times which created a patchwork effect. Finally, the owner reached out to a flooring professional to discuss a new renovation solution. 

Seamless X60QOS and X65QOS line pipes are widely used for offshore and onshore Sour Service applications. Sour Service refers to the risk of hydrogen related cracking as Sulfide Stress Cracking (SSC). The International standard (NACE MR0175 / ISO 15156) provides requirements for assessing the resistance to SSC, specifically on how to qualify for use in region 3 of the environmental severity diagram (Figure 1 in paragraph 7.2.1.2 of part 2). It is requested to expose materials in an acid solution saturated by 1 bar of H2S (NACE TM0177 Solution A) and to apply a tensile stress above 80% AYS by means of different methods: uniaxial tensile, C-ring or Four-Points Bend. However, for very sour fields presenting H2S partial pressures much higher than 1 bar, the preservation of the SSC resistance might be questioned and is presently a major concern for the O&G industry.
The present paper is dedicated to the evaluation of the SSC resistance of seamless quenched and tempered X65 grades, including the girth weld in the standard NACE TM0177 Solution A up to 15 bar of H2S partial pressure. Corrosion tests consisted of four-point bend tests performed in autoclave vessels. Different test configurations were investigated as specimen sampling locations through the wall thickness and surface state preparation.

Seamless X60QOS and X65QOS linepipes are widely used for Sour Service offshore and onshore applications. Sour Service refers to the risk of hydrogen related cracking, such as by Sulfide Stress Cracking (SSC). The International standard NACE MR0175 / ISO 15156 provides requirements for assessing the resistance to SSC, specifically on how to qualify for use in region 3 of the environmental severity diagram (Figure 1 in paragraph 7.2.1.2 of part 2). Qualification requires exposing materials in an acid solution saturated by 1 bar of H2S (NACE TM0177 Solution A) and to apply a tensile stress above 80% AYS by means of different methods: uniaxial tensile, C-ring or Four-Point Bend. However, for very sour fields presenting H2S partial pressures much greater than 1 bar, the preservation of the SSC resistance might be questioned and is presently a major concern for the O&G industry. 

Apart from the well-tried cellulosic electrodes, in the range from E6010-E9010, there are
also low hydrogen grades of weld consumables, which are used in vertical downhill
position - commonly called as BVD (Basic Vertical Down) electrodes. In addition, the
seamless flux cored wires, are gaining prominence in the welding industry as a better
solution compared to the conventional cellulosic electrodes.
The development of BVD electrodes started because of the desire to use high-strength
TM pipe steels with relatively high toughness (e.g. X80). Cellulosic electrodes could not
meet the requirements for cold crack resistance and high toughness properties of the
weld metal. To a high degree, economical efficiency is determined by the achievable
deposition rate and the possible welding speeds. In comparison to basic vertical-up
electrodes, significant time advantage of 40-50% can be achieved with the use of BVD
electrodes for the fill and cap layers.
Seamless Flux Cored wires for pipeline applications follow a different manufacturing
approach compared to the conventional folded techniques and are much reliable with
consistent performance in terms of weldability and quality. The seamless FCAW wires,
offers a unique and trustworthy solution in terms of arc stability and low defect rates.
These wires are also suitable to be used under sour service applications having been
tested for Hydrogen Induced Cracking (HIC) and Sulfide Stress Cracking applications.