The world of chemicals is a vast one, with each chemical combination triggering unique reactions. For Tom Sandbrook, an Engineering Fellow who works with applications such as hoses, couplings, valves, and pipes, knowing how each chemical will react to certain metals is crucial in order to avoid both minor, and fatal accidents.
Stainless Steel World Americas had the opportunity to sit down with Sandbrook in Houston, Texas, during the Managing Aging Plants USA 2018 Conference and Exhibition, and learn about his many contributions to industries such as mining, and oil and gas. His experience with, and knowledge of corrosion-resistant alloy (CRA) testing and evaluations are coming into play in his current position at an industry-leading chemical company, Chemours.
By Catarina Muia and Angelica Pajkovic
Sandbrook has thought about it a million times over, and still does not quite know what first sparked his interest in engineering. “I have come to the conclusion that I was a baby, born an engineer. I can never remember a time when I said I was going to be anything but an engineer,” Sandbrook explains. “I grew up in the 1960s, and you know, every little kid in the 1960s was enthralled with the space program. So honestly, it was probably the space program that started it all.”
With the rest of his family working in the mining industry, he always thought he was going to be a miner. “My brothers and I planned to do something different, but they all ended up being miners, and I was the only one who ended up doing something else.”
Sandbrook attended Rensselaer Polytechnic Institute for Mechanical Engineering in New York, and graduated in 1980. He then completed his master’s degree in Industrial Engineering at Rensselaer in 1981. His journey after college took him to various industries where he worked in a few different positions. Today he is an Engineering Fellow at The Chemours Company.
A role in all industries
In 1981, Sandbrook had just completed college and oil prices were sky-rocketing due to the second Arab Oil Embargo. “I decided I was going to save the world and work in synthetic fuels and synfuels, so I went to work for Conoco.” At the time, Conoco owned the second largest coal company in the U.S.A., and had an active synfuel project going on to make methanol out of high sulfur coal in Ohio.
“We were doing the pilot work and I was going to go right into the production plant. Fortunately, or unfortunately, oil prices crashed in 1983 and all the programs in synfuel were going to shelf,” Sandbrook recalls. “Conoco, Exxon, Chevron, and everyone else in the industry shelfed their synfuel programs. Choosing to leave Conoco, I ended up in the coal division, where I coal mined and did coal beneficiation at DuPont.”
Sandbrook stayed with DuPont for 35 years, and had the opportunity to work on projects in titanium mines in Florida. “After that, I went into heavy chemicals with different DuPont sites, making Aramids, Nomex, and Kevlar or agricultural products,” Sandbrook says. “The common thread of all those chemical processes, is that they are all very hazardous. Making chlorines, ammonia, hydrofluoric acid, sulfur trioxide, pretty much the higher risk chemicals at DuPont, or now, Chemours.”
His time at DuPont involved a lot of work in mechanical integrity and quality assurance; ensuring that the chemicals were going to stay in the pipe. In 2007, Sandbrook started leading the North America Effort for DuPont’s Mechanical Integrity and Quality Assurance Program. “I was responsible for the North American process equipment QA/QC, in-service tests and inspections, maintenance procedures – essentially adhering to Occupational Safety and Health Administration (OSHA) 1910.119 requirements,” Sandbrook explains. “After doing that for quite a few years, DuPont and Chemours split, and I had the opportunity to move back to Chemours as an engineer.”
A day in the life
As an Engineering Fellow, one of Sandbrook’s main responsibilities involves consulting. A typical workday is not very structured and can change in a matter of minutes as a result of a single phone call. “I like that aspect of the job; it is always something new. I am always learning, and there is a lot of autonomy to set strategy, set goals, and set designs,” he explains.
With so much responsibility, it is important that Sandbrook prioritizes, even if it might be difficult. “With so many different emergencies, projects, and personal programs I want to see happen, it can be hard at times to keep everyone satisfied and maintain a nice balance.” However, he continues to explain that it is always his goal to service plants first. “If there is a plant with a problem, that situation will typically take precedence over a project, or a program-type activity.”
Applications with CRAs
Sandbrook has been working with valves for more than 20 years, and because of the toxic nature of the chemicals he deals with, he has come to understand that purchasing the best valve technology available is extremely important.
“We have a lot of unique needs for valves because of their requirement for absolute containment. Many of our materials are very corrosive, so containment can be challenging,” Sandbrook explains. “Our valves have a minimum run-life of two years with maintenance aside, which is why we try to run everything for two years without a shutdown. Some of these valves may not cycle once or twice in that two-year frequency, however we need to make sure when they are called upon to cycle, they actually work.” Choosing the correct valves helps avoid risky situations such as a leak-out, a leak-through, or a non-functionality.
“The highest risk would be a major leak-out, corrosion to a body, however fugitive leaks at valve packing always increase with time as the stem corrodes,” Sandbrook explains. “Although it does not happen often, there is always that chance that it will, so we really take a look at the metallurgy of the valves. Looking at all the materials in the valve is critical to its performance. We specify very high reliability valves. It is not unusual to purchase valves that cost between USD$1,000 to USD$2,000 per inch diameter,” he says.
The prices of the valves are determined by the specific alloys from which they are manufactured. “The material construction of a valve is often significantly different from the pipe it is attached to, due to the turbulence and accelerated carrion that results. It is not unusual to use Teflon®-lined or C-276 valves in a stainless-steel pipe,” Sandbrook explains. “In our experience, the bellows, even in the parts per million HCl, will need Hastelloy materials. That is one of the reasons our valves end up being so expensive, because we have a lot of exotic alloys in them.”
Throughout the last 10 years, Sandbrook explains that the company has put a major emphasis on the maintenance of the valves, “we have our sites identify what we call ‘critical valves’. The valves that are containing the most hazardous chemicals need to be able to perform the normal valve functions such as opening, closing, and not leaking, in order to keep the plant safe,” he says. Whether the site has 5 or 10,000 valves, around 10% are identified as critical valves. “These valves get put into a special maintenance program and receive special attention. This is extremely important for us, because we might have seen a valve and thought it was okay, but when they have been putthrough the special program, issues have been found. There is a huge commitment that needs to be made, but it works. A program like this, makes having a good relationship with your valve supplier or distributor, very important.”
As the majority of Chemours’ processes are based on chlorine or hydrogen fluoride (HF), any residue left in the hoses will get hydrolyzed from strong acids, eventually leading to loss of containment. In order to prevent this, Sandbrook believes the best material to fabricate their hoses from, is hastelloy.
“Most of the hoses we use are metallic, and because the welding of a metal hose is an art form, we only allow one company in the U.S.A. to fabricate our hoses,” Sandbrook explains. “Our companies have worked together for many years and have developed a reliable welding process. Welding very, very thin pieces of metal to a coupling, to all these metal strands, is very hard to do perfectly. Given the weld is the weakest part of the hose, getting it right, reliably, is critical.”
With the hoses being expensive and very specially-made, it is important that each hose is being used for its full life cycle. Sandbrook explains that each site must complete mandatory hose maintenance testing inspection programs, and mandatory end-of-life programs. “If you are just taking a hose, and you run it for a year and then throw it out, you do not know that the hose actually needed to be changed on that day, or if it would have been good for another day. We have a requirement for all sites; a post-mortem on the hose, even when it has been removed because its life expectancy is up. This way, we have the ability to develop reliability data to say the hose can last a lot longer than we originally thought it could.”
Being a mentor
Although he has so much going on as a Fellow Engineer, Sandbrook admits that his favorite part about his job is mentoring people. While visiting different sites regularly, Sandbrook has the opportunity to train people in the different technologies that he specializes in. “If someone calls me up and asks me a question that I think they should know, I will not answer it for them. I will get on a Skype meeting with them because it is all remote, and I will show them where the information is, but I will make them get out their computer to get the information, that way they actually learn,” says Sandbrook. “Mentoring has actually become more of a passion. I really enjoy teaching. I always tell people I have a lot of things bouncing around in my head, and I have got to get some of it out to them before I retire.”