HIC Testing
Steel’s resistance to hydrogen-induced cracking in moist H2S conditions can be assessed via HIC testing. You may test your steel in a number of various ways. The GMax test and the HIC test are two examples of these assays. You can use these tests to find out how resistant the steel in your line pipe is to hydrogen-induced cracking.
HIC Resistance of Line Pipe Steels for Mild Sour Environments
The HIC Resistance of line plates steels is measured using a variety of HIC resistance tests. The techniques utilised in these tests and the variables used to calculate the steel’s resistance differ. The solutions used in these experiments are frequently those that are most similar to the actual corrosive environment. Additionally, the testing are carried out in a lab setting. Depending on the kind of material being tested and the testing environment, different parameters are employed. Frequently, the test findings are followed up on for several months.
In comparison to tests conducted in situations with acidity, HIC resistance testing often have fewer parameters. The test results occasionally fell outside the advised ranges. This can be the result of a decline in strength. A reduction in the SOHIC threshold stress may have also been brought on by the loss of strength.
The threshold stress for SOHIC is normally based on the NACE TM0177 tensile tests. In these tests, steels are tested at 30%, 50%, and 90% yield. The tests are sectioned after exposure to measure the presence of stacked arrays of cracks. The threshold stress is then measured and reported as a design value for the minimum tensile strength.
Types of HIC Test Tanks
Hydrogen enriched aquatic environments can examine the effects of corrosion using a variety of hydrogen induced cracking (HIC) test tanks. This experiments are intended to investigate the effects of corrosion and embrittlement on metal samples.
The buildup of hydrogen molecules in a metal’s crystal lattice causes the damage that results from hydrogen-induced cracking. As a result of these atoms’ inability to diffuse out of the metal, the metal’s lattice develops a number of flaws. Blisters and micro-fissures are the end outcome.
High-hardness and low-alloy steel is most frequently affected by hydrogen corrosion.The Carbon steel is susceptible to it as well, particularly if it is exposed to moist hydrogen sulphide. The condition may pose a serious risk to a functioning structure’s safety. During hydraulic testing, it has resulted in the collapse of pressure vessels and bridges.
Clustered and SOHIC are the two different forms of HIC. Individual cracks that are concentrated together are referred to as clustered HIC. The nearby cracks are connected by the hydrogen pressure created by the fractures’ formation. SOHIC can cause a catastrophic loss of containment and is more harmful.
Hydrogen Induced Cracking in Wet H2S Environments
Hydrogen-induced cracking can happen during high-temperature procedures. When hydrogen segregates within a metal and causes it to blister, the process takes place. The majority of ferrous alloys go through this process.
Almost any piece of equipment that operates in these conditions is susceptible to wet hydrogen sulphide (H2S) damage. Explosions and fires can result from this kind of damage. There are ways to lessen these dangers, though.
Wet H2S damage is intricate and can take many different forms. Making the right decisions for equipment inspection and repair requires that you have a thorough understanding of the various types of damage. You can prevent unanticipated failures and guarantee the secure running of your assets by comprehending these patterns.
This type of damage is especially common in the gas and oil industry. For example, pressure safety relief valves can be vulnerable to hydrogen damage. Pipelines and tubing made of carbon steel can also be susceptible.
H2S is highly toxic and can cause a variety of degradation mechanisms. One of the most common mechanisms is hydrogen embrittlement. The secondary effect of hydrogen embrittlement is the appearance of sulfide stress cracking (SSC).
Comparison Between HIC Test & GMax Test
The GMax vs. HIC test has been the subject of debate in recent years regarding sports safety. Impact able attenuation and concussion protection are measured by tests.
The GMax test specifically assesses the effect of a 20-pound flat rocket dropped from two feet. The HIC test, on the other hand, mimics a head contact with a playing surface. It evaluates impact attenuation, head deceleration rate, and deceleration consequences.
Both tests are exact and accurate. A greater Gmax number indicates that more impact is being absorbed by the playing surface. On the other side, a lower HIC score indicates a reduced risk of concussion from the playing surface.
Learning more about the GMax and HIC tests is definitely time and money well spent. They can assist you in selecting a secure, long-lasting playing area for your sports team. The routine upkeep of your turf field should include both tests.