July 26, 2011
Welding and fabricating using exotic metals requires a special touch, one that Schwabel Fabricating Co., Tonowanda, N.Y., has built its business on for the last 53 years.
Exotic metals in many ways resemble exotic animals. In certain circumstances their behavior is unpredictable, they should be handled by trained professionals only, and they possess a rather mysterious and intimidating aura. Welding and fabricating using exotic metals requires a special touch, one that Schwabel Fabricating Co. Inc., Tonawanda, N.Y., has built its business on for the last 53 years.
A small shop of 15 people, Schwabel has made a name for itself designing and fabricating large pressure vessels, heat exchangers, and storage tanks, as well as rolling shells for heat exchangers. They specialize in fabricating and welding with nickel, nickel alloys, aluminum, titanium, and various clad materials.
“We’re pretty small and pretty nichey. We make very large, very heavy items, and we tend to use exotic materials, which I think scares off a lot of basic fabricators. Certainly the size [of the components] is a way to restrict the market too,” said Keith Waldron, company owner and president.
While business hasn’t exactly been booming, explained Waldron, the company has kept busy. They’ve been actively quoting new jobs so far in 2011, which is an encouraging sign that a pickup is on the way. Much of this is due to the company’s niche in large fabrications using specialty metals as well as its ability to join dissimilar metals. This, Waldron added, is what separates Schwabel from most basic fabricating shops and what initially attracted him to the business.
Waldron purchased the family-owned and -operated company last December and estimates that only 25 to 30 shops in the country do the type of work Schwabel does, which keeps the market small but competitive.
“There might be 15 to 20 companies around the country, certainly fewer than 25, that are willing to make things that large; that have the crane capacity, that have the machinery, and that are willing to do the welding on nickel or nickel alloys or titanium. A typical fabrication shop might have a dozen code-approved welding procedures; we have in excess of 125 approved welding procedures,” explained Waldron.
Niche fabrication doesn’t come cheap. First it is imperative that welders stay current on certain welding procedures. That’s why they must weld using a particular process within six months, which is standard for code. This is a task that is overseen by Schwabel Quality Control Manager Dave Purcell.
It takes work to stay relevant, particularly when the fabricating and welding practice must comply to strict guidelines and welding codes.
Added Waldron, “If somebody’s getting near the six-month point and they haven’t welded a certain process that we anticipate they’re going to need to weld, we make sure to give them more time on it. Dave has to keep track and make sure all of our welders are current.”
Second, welding with exotic metals and joining them with dissimilar metals presents a challenge that, in most cases, can be mastered only by skill.
“The problems occur when you have to do a combination weld, where for instance nickel is being welded to carbon. If it’s in contact with the process side, you worry about carbon contamination in the weld, which will [cause it to] corrode easier than the nickel itself,” Purcell explained.
Contamination, penetration, and mechanical strength are all important factors, so welds must pass a number of tests, such as a ferroxyl test, which checks for the presence of carbon within the weld.
Much of the success, Purcell said, depends on the welder’s familiarity with the process as well as his execution and technique.
“That’s one of the … I won’t say problems, but it’s process- and technique-oriented. You’ve just got to make sure the carbon doesn’t bleed through,” he added.
Another potential issue is finding and training welders. This especially rings true for Schwabel, which, like many businesses, employs welders who are on average 50 years old. The precision, care, and attention to detail that are necessary with regard to the temperature settings and current settings all speak to the skill level expected of the welders.
“There are four or five things I feel I need to do over the next couple of years, and one of them is to make sure I have a bench, so to speak, of replacement players as we start to retire out those of us who approach that age,” Waldron said.
Waldron is preparing now and is encouraged by the welding talent he is seeing coming out of trade schools. He is working hand-in-hand with the local workforce development consortium to get in touch with the individuals who possess the skills necessary to weld under such highly scrutinized conditions.
While the manufacturing sector continues to make national headlines on its much-debated return to prominence, companies like Schwabel quietly make noise by turning out large-scale components, proving that specialty fabrication can survive and thrive even in the most unpredictable business environments.
Schwabel recently completed work on a steam chest for Georgia Gulf Corp., a facility located in Louisiana that produces sodium hydroxide.
Also called caustic soda, sodium hydroxide is a byproduct of chlorine production, Waldron explained. During the manufacturing process, sodium hydroxide is sent through four successive heat exchangers. Each one reduces the amount of water, further concentrating the sodium hydroxide. This particular steam chest was fabricated as the second chamber, also referred to as second effect, which is the third in a series of four successive heat exchangers. Often the fourth and third effects require only stainless steel components, but by the time the highly concentrated chemical reaches the second and first effects, it is imperative that the interior be nickel-plated because of nickel’s ability to resist the corrosive characteristics of the chemicals.
he vessel, 20 ft. long, 13 ft. in diameter, weighing upwards of 104,000 lbs., and fabricated with more than 2,000 tubes of nickel, is worth roughly $2.5 million (see Figure 1). The project called for 2-in. carbon steel tube sheets which were explosion-welded with 0.5- in. nickel. Schwabel fabricators then cut that material into a circle, rolled the shell, and then welded the seams together using submerged arc welding (SAW). After plasma cutting the circles and drilling 2,000 holes into the vessel, the fabricators placed 2,022 tubes of E-Brite® high-purity, high-nickel-content ferritic stainless steel inside the holes and joined with gas tungsten arc welding. Not all went according to plan.
“Because those materials are dissimilar—the nickel on top of the carbon—we experienced some bowing or deflection when we welded that into the tube sheet. When heated, they expanded at a different rate. So we had to fixture it back together and take the bow out. We did some calculations and the rolling required a little more work than what might typically be experienced,” Waldron said.
Delays notwithstanding, the project took about 50 weeks to complete. The company is currently working on a similar steam chest, this one having 1.5-in.-thick pure nickel, and has submitted several quotes, one of which is for a first effect steam chest. Waldron remains confident in his company’s niche fabricating expertise and plans on employing his sales and marketing background to expose his company to a more diverse group of potential customers.
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