Today We Celebrate Our Veterans

Veterans Day

Veterans Day is a day of observance and celebration for those who have served in the United States military. Veterans Day was originally called Armistice Day because of the November 11 Armistice that ended World War I. In 1954 it was officially changed to Veterans Day to include Veterans of all wars. This holiday honors those who took an oath to defend the United States and our Constitution, from all enemies, foreign and domestic. Through the observance of Veterans Day, we remind ourselves of our Veterans patriotism, love of country and willingness to serve and sacrifice for the common good.

Hotfoil-EHS thanks our Veterans, past and present, for serving our country and protecting our freedom.

The Importance of Pre-Weld Heating

Pre-Weld Heating
Pre-heating and metal prep before welding a large section of pipe.
The process of pre-heating steel prior to welding is important to understand. In general, there are two primary reasons to heat treat prior to welding.

First, it increases the temperature of the target material, resulting in a controlled (slower) cooling rate of the target material, as well as that of the weld. Thicker areas of steel, typically 1/2 inch or greater, and high-strength low-alloy steels (HSLA) are prone to the formation of weakened crystalline microstructures if the weld cools too quickly. These weakened crystalline microstructures are called martensite.  Martensite is a steel crystalline structure critical to the steel's hardness and strength; too much martensite leaves steel brittle; too little leaves it soft.

When welding, martensite can form in the newly deposited weld metal, the base target material, or
the HAZ (heat-affected zone). Applying the proper amount of pre-heat prior to welding will assist in preventing the formation of martensite. Pre-heat temperatures and soak times are dependent on the target materials type, thickness, grade, and carbon equivalency. There is ample temperature and time pre-heat information available on the Internet and from industry associations, and one should refer to this information prior to welding.

Pre-Weld Heating
Ceramic mat heaters used to pre-heat pipe spool piece.
Second, preheating also results in the elimination of condensation (moisture) prior to the welding procedure. The presences of moisture is problematic because the water will change phase (from liquid to gas) during welding. This phase change can releases trace amounts of hydrogen, and lingering hydrogen can be absorbed into the weld. When hydrogen molecules are trapped in the newly welded metal, they affect the metals grain boundaries and impose a risk of higher weld failure. As a result, removing moisture before welding is strongly recommended.

Uniformly preheating the target material prior to welding, and then insulating the target area after welding, provides an adequate cooling rate allowing hydrogen to diffuse out of the weld joint, preventing hydrogen cracking.

For more information about the equipment and processes required for weld pre-heating, contact Hotfoil-EHS, a world leading manufacturer of heat treatment equipment. They can be reached by calling 609-588-0900 or visit their web site at https://hotfoilehs.com.

US Power Grids, Oil and Gas Industries, and Risk of Hacking


A report released in June, from the security firm Dragos, describes a worrisome development by a hacker group named, “Xenotime” and at least two dangerous oil and gas intrusions and ongoing reconnaissance on United States power grids.

Multiple ICS (Industrial Control Sectors) sectors now face the XENOTIME threat; this means individual verticals – such as oil and gas, manufacturing, or electric – cannot ignore threats to other ICS entities because they are not specifically targeted.

The Dragos researchers have termed this threat proliferation as the world’s most dangerous cyberthreat since an event in 2017 where Xenotime had caused a serious operational outage at a crucial site in the Middle East. 

The fact that concerns cybersecurity experts the most is that this hacking attack was a malware that chose to target the facility safety processes (SIS – safety instrumentation system).

For example, when temperatures in a reactor increase to an unsafe level, an SIS will automatically start a cooling process or immediately close a valve to prevent a safety accident. The SIS safety stems are both hardware and software that combine to protect facilities from life threatening accidents.

At this point, no one is sure who is behind Xenotime. Russia has been connected to one of the critical infrastructure attacks in the Ukraine.  That attack was viewed to be the first hacker related power grid outage.

This is a “Cause for Concern” post that was published by Dragos on June 14, 2019

“While none of the electric utility targeting events has resulted in a known, successful intrusion into victim organizations to date, the persistent attempts, and expansion in scope is cause for definite concern. XENOTIME has successfully compromised several oil and gas environments which demonstrates its ability to do so in other verticals. Specifically, XENOTIME remains one of only four threats (along with ELECTRUM, Sandworm, and the entities responsible for Stuxnet) to execute a deliberate disruptive or destructive attack.

XENOTIME is the only known entity to specifically target safety instrumented systems (SIS) for disruptive or destructive purposes. Electric utility environments are significantly different from oil and gas operations in several aspects, but electric operations still have safety and protection equipment that could be targeted with similar tradecraft. XENOTIME expressing consistent, direct interest in electric utility operations is a cause for deep concern given this adversary’s willingness to compromise process safety – and thus integrity – to fulfill its mission.

XENOTIME’s expansion to another industry vertical is emblematic of an increasingly hostile industrial threat landscape. Most observed XENOTIME activity focuses on initial information gathering and access operations necessary for follow-on ICS intrusion operations. As seen in long-running state-sponsored intrusions into US, UK, and other electric infrastructure, entities are increasingly interested in the fundamentals of ICS operations and displaying all the hallmarks associated with information and access acquisition necessary to conduct future attacks. While Dragos sees no evidence at this time indicating that XENOTIME (or any other activity group, such as ELECTRUM or ALLANITE) is capable of executing a prolonged disruptive or destructive event on electric utility operations, observed activity strongly signals adversary interest in meeting the prerequisites for doing so.”

Differences Between Arc Welding Processes

Arc welding processes are based on fusion. Fusion requires closeness and cleanliness at the atomic level, both of which can be achieved by shielding the molten puddle with gas or slag. There are several types of arc welding processes as follows:

Shielded Metal Arc Welding (SMAW)

An electric arc is produced between the end of a coated metal electrode and the steel components to be welded (Figure 1). The electrode is a filler metal covered with a coating. The electrode’s coating has two purposes:
  1. It forms a gas shield to prevent impurities in the atmosphere from getting into the weld, and 
  2. It contains a flux that purifies the molten metal.
SMAW is almost exclusively a manual arc welding process. Because of its versatility and simplicity, it is particularly dominant in the maintenance and repair industry. The most common quality problems associated with SMAW include weld spatter, porosity, poor fusion, shallow penetration and cracking.
Figure 1: Shielded Metal Arc Welding (SMAW) 



Gas Metal Arc Welding (GMAW)

Gas Metal Arc Welding (GMAW) is fast and economical. As shown in Figure 2, a continuous wire is fed into the welding gun. The wire melts and combines with the base metal to form the weld. The molten weld metal is protected from the atmosphere by a gas shield that is fed through a conduit to the tip of the welding gun. The process may be semi- automatic or automated. It cannot be used in a windy environment as the loss of the shielding gas from air flow will produce porosity in the weld.
Figure 2: Gas Metal Arc Welding (GMAW)


Flux Cored Arc Welding (FCAW)

Flux Cored Arc Welding (FCAW) is similar to the GMAW process and is usually performed by semi/full automatic methods. The difference is that the filler wire has a center core that contains flux (see Figure 3). With this process it is possible to weld with or without a shielding gas, which makes it useful for exposed conditions where a shielding gas may be affected by the wind.
Figure 2: Flux Cored Arc Welding (FCAW)


Submerged Arc Welding (SAW)

Submerged Arc Welding (SAW) is usually performed by semi/full automatic or handheld methods. As shown in Figure 4, it uses a continuously fed filler metal electrode. The weld pool is protected from the surrounding atmosphere by a blanket of granular flux fed at the welding gun. It results in a deeper weld penetration than the other processes. However, only flat or horizontal positions may be used.
Figure 4: Submerged Arc Welding (SAW)



Process Selection

Selection of the welding process is typically left to the contractor. The characteristics of the various processes are:
  • SAW: long, big, semi/full automatic or handheld methods.
  • FCAW: semi/full automatic methods.
  • SMAW: small, miscellaneous, repair, tack welds and handheld method.
  • GMAW: semi/full automatic methods in shop.
https://hotfoilehs.com  |  609.588.0900 

Reprinted from the Michigan Department of Transportation Field Manual for Structural Welding.