How Material Advancements Have Improved Seals and Increased Gasket Service Life

Aaron Larson

Most people probably don't think about gaskets very often. Yet, they reap the benefits provided by gaskets every day of their lives. From the electricity they use—produced by power plants that have literally thousands of gaskets installed—to the cars they drive and the running water they drink and bathe in, gaskets support almost every aspect of modern life.

The term gasket can be defined as a material or combination of materials clamped between two separable pieces of a mechanical joint, such as a valve or pipe flange. Its function is to create a seal between the pieces and maintain the seal for an extended period of time. Frankly, without gaskets, most equipment couldn't operate, at least not for long. Every system that contains a liquid or gas requires seals, and gaskets are one of the main products used to keep fluids in and contaminants out.

In the book Gaskets and Gasketed Joints, edited by John H. Bickford and published in 1998 by CRC Press (an imprint of Taylor & Francis Group), Daniel E. Czernik provided a brief history of gaskets. He wrote: "Gaskets have been utilized from the advent of the industrial revolution through the steam engine period and from the beginning of the evolution of the internal combustion engine. From the advent of the internal combustion engine, almost every material imaginable, from extremely hard to extremely soft, has been (and still is being) utilized for gaskets, including leather, paper, metal, cork, rubber, sponge, and plastic."

In the mid-1800s, the development of vulcanization allowed rubber to become a common gasket material. By the early-1900s (Figure 1), the proliferation in the use of asbestos in products of all types extended to gaskets, as the material was highly resistant to heat, wear, alkalis, and acids, as well as having great flexibility—all desirable properties for long-lasting sealing systems.

Czernik recounted an interesting anecdote in his history of gaskets. He explained that gasket failure, particularly of engine head gaskets, was often the cause of racecars not finishing the Indianapolis 500 in the 1920s and 1930s. "After a couple of hundred miles, the track became so slippery from the oil leakage that drivers felt they were driving on ice," he wrote.

Today, engine gaskets are extremely reliable. Many automobile owners have never experienced a head gasket failure, some over decades of driving. In fact, it's not uncommon for a heavy-duty diesel engine in a semi-tractor to travel more than a million miles before requiring a head gasket replacement. Based on impressive operation such as that, it's obvious that years of research and development have paid off in much better gaskets.

Czernik noted that cork was one of the first materials used in gaskets. Over the years, cork was combined with polymers to create composites that provided better seals. Paper has been another common material used in gaskets. The fibers used in paper gaskets have commonly been cellulose. Over time, manufacturers improved paper gaskets by saturating the fibers with glycerin and animal glue, treating the mixture with formaldehyde, and drying it in an oven. The product, known as "treated fiber," is still used extensively today.

Jörg Latte, another contributor to Gaskets and Gasketed Joints, wrote in the book, "Flat gaskets for industry in the modern sense were invented by Austrian engineer Richard Klinger about 100 years ago [see sidebar], based on asbestos and rubber. Due to their success, these first products attracted numerous imitators, and soon many materials of various qualities were available."

Latte suggested that the large number of options available created confusion, which led some inventors to search for "a universal gasket suitable for all applications." However, Latte explained, "Such gaskets do not and cannot exist." Rather, he suggested the goal of developing a universal gasket can only marginally be approached by increasing the application ranges of gasket materials.

"An industrial engineer and user of gaskets should always become or poor gaskets—there is only a correct or an incorrect selection of a gasket for a given application, since many other parameters play a part in this matter."

POWER magazine has been covering new technology and reporting on power industry best practices for 140 years. Founded in 1882, the publication has published countless technical articles on topics of all types, including pieces focused on gaskets. Although cases could be found from many issues in POWER's archives, the following are a couple of examples pulled from articles published more than 110 years ago.

In the June 11, 1912, issue of POWER, the "Devo Gasket" (Figure 2) was featured in a short article. The gasket was manufactured by the Goetze Gasket & Packing Co., in Brunswick, New Jersey. The article explained that the gasket was intended for high and low pressures, as well as for superheated steam. It consisted of "a corrugated steel gasket entirely embedded in an asbestos covering, which is graphited throughout. The gasket is 1/8 in. in thickness, but it can be compressed to 1/16 in." The article continued, "Being deeply corrugated, this gasket will make a steam-tight joint even where the flange surface is unusually rough." Somewhat surprisingly, similarly designed gaskets still exist today.

In an article published in the Feb. 13, 1912, issue of POWER, the topic of proper gasket cutting and installation was addressed. "The two principal points regarding a good packing job are the cutting of the packing and the putting it into place," Scott Norton of Springfield, Ohio, wrote.

Concerning the cutting of sheet packing, Norton explained, "It is all right to place the packing against the flange and tap it lightly with the hammer for marking, but on no account hit sufficiently hard to cut the gasket; use the knife for that, as the hammer tears it. To save time, men will sometimes cut the bolt-holes out with the peen end of the machinist's hammer. This is bad practice and is the cause of many blowouts at the bolt-holes."

The article further explains, "Equally as important as cutting the gasket and putting it in place is the coming up on the bolts with the nuts." Norton wrote: "Just watch a first-class engineer come up on the bolts on his engine cylinder head or steam chest when replacing them. Note how carefully he comes up on them all, little by little, paying particular attention to each one in turn as the task is nearly done. One or two bolts are not put under a severe strain while the rest are being brought up to proper tension, but the pressure is divided equally and gradually on them all. The inclination to come up tight first on one bolt, then follow with the next, and so on, is the cause of many blowouts at the bolt-holes."

One last lesson shared in the article involved cost. The article says, "The cheapest part about any gasket is its original cost; putting it in is the expensive part." Perhaps the most surprising thing is that these lessons still resonate today, more than 110 years after being published in the pages of POWER magazine. This just goes to show that good engineering practices are timeless.

Czernik explained that paper gasket manufacturing went through a "major revolution" after World War II with the introduction of the beater-add (BA) process. "In this process, elastomers, fibers, and fillers are mixed with water in a slurry. The slurry is then deposited on a conveyor belt and the water drawn off. After heating, the BA facing is ready to be made into gaskets," he wrote.

The BA rubbers include nitriles, styrenes, acrylics, fluorocarbons, and others. Czernik noted that blends of the rubbers are common. "Subsequently, composite gaskets incorporating beater-add facing materials and either a perforated or a solid steel reinforcing core became the dominant products for sealing various engine gasketing applications," he wrote.

After it became widely recognized that asbestos increases the risk of several serious diseases, including asbestosis, mesothelioma, and lung cancer, many governments began to restrict its use. According to the International Ban Asbestos Secretariat, 67 countries have now banned asbestos including all Organisation for Economic Co-operation and Development (OECD) countries except Costa Rica, Mexico, and the U.S. Even China has banned asbestos.

As a result of the restrictions, many materials manufacturers worked in earnest to develop alternatives to asbestos. With a wealth of resources behind them, they have been largely successful. Today, compressed non-asbestos materials are available that consist of non-asbestos fibers, such as fiberglass or aramid fibers, combined with rubber. This formulation has proven to have very good temperature and pressure performance, and often serves as a suitable replacement for asbestos-containing materials.

There are dozens of different gasket materials available to meet engineering design specifications for almost any power plant system. The following are some of the broad gasket types that exist:

■ Closed-cell sponge rubber materials.■ Compressed non-asbestos.■ Cork.■ Electrical insulation.■ Electromagnetic interference (EMI) and radio-frequency interference (RFI) shielding.■ Felt.■ Fiber.■ Flexible graphite.■ Foam.■ High-temperature materials.■ Metal alloy.■ Open-cell sponge rubber materials.■ Plastics.■ Rubber molding compounds.■ Rubber.■ Semi-metallic (Figure 3).

Among the common materials and names of products used in some of the gasket types listed above are: Butyl, Cellulose, Chomerics, Cloth-Inserted, Elastomers, EPDM (Ethylene Propylene Diene Monomer), Flexible graphite, Formex, HDPE (High-Density Polyethylene), Hitex, Hypalon, Latex, LDPE (Low-Density Polyethylene), Mylar, Neoprene, Nitrile, Nomex, Nylon, Phenolic, Polyester, Polyurethane, PTFE (Polytetrafluoroethylene), PVC (Polyvinyl Chloride), Silicone, UHMW (Ultra High Molecular Weight), Urethane, Vinyl, Viton, Wool Felt, and others.

According to Latte, the most important properties for sealing materials are:

■ Loading capacity.■ Sealability.■ Elastic behavior of a sealing material.■ Capacity for chemical resistance against media.

Latte noted that tensile strength of a material "is not of particular importance for quality consideration, because no tensile forces are usually exerted on a gasket, only pressure forces." Nonetheless, he suggested the determination of tensile strength is important for production purposes because "it is a simple and rapid method for demonstrating production stability and reproducibility. Other methods, apart from the determination of compressibility and recovery, are too time-consuming and expensive to be used to control production quality," Latte wrote.

When it comes to choosing the best gasket material to use in a given application, it's often best to consult with an expert. Several factors must be evaluated to ensure the material chosen is appropriate for the intended purpose. Some of the key considerations are:

■ Temperature. What temperature range must it withstand?■ Pressure. What pressure range must it withstand?■ Media. What fluids or materials will it be exposed to? Are they abrasive or corrosive?■ Ultraviolet and ozone exposure. Will it be exposed to sunlight and ozone?■ Product standards. Is it subject to any industry-specific product requirements? Does it need EMI shielding properties?■ Industry standards. Is it subject to any other industry-specific standards?

While there are multiple reasons a gasket might need to be replaced, the most common is after a system or component has been disassembled for maintenance. That's when having a reliable supplier that can provide the gasket you need, when you need it, is critical. One company that's been providing gaskets to the energy industry for 75 years is Lamons. The company was founded in 1947 by W.A. Lamons and has been distributing quality gaskets to the oil and gas, and petrochemical industries, ever since. Lamons has also supported customers in the U.S. military, pulp and paper, food and beverage, water and wastewater, power generation, and pharmaceutical sectors.

Headquartered in Houston, Texas, Lamons has grown into one of the largest privately held gasket, seal, bolt, and hose assembly manufacturers in the world. Its growth has been partly fueled by acquisition. In 1985, Lamons acquired Richard Gasket Company, and a few years later, in 1988, it took over Packing and Gasket Engineering. The company purchased Industrial Bolt and Gasket, a Beaumont, Texas-based company in 1997. In 2010, Lamons acquired South Texas Bolt and Fitting, which made the company one of the most capable specialty fastener manufacturers in the world.

IsoTek was purchased in 2012, which added isolation gaskets, sleeves, and washers to the company's product portfolio. With the addition of hoses in 2016, Lamons fulfilled its vision of leading global markets in safety sealing and attachment solutions. In 2019, Lamons became part for the First Reserve family, a leading global private equity investment firm exclusively focused on energy.

Lamons has a manufacturing facility in Houston totaling 300,000 square feet, which includes a 64,000-square-foot addition (Figure 4) constructed during the COVID pandemic, and it has another 30,000-square-foot facility in Denver, Colorado, specifically dedicated to the company's IsoTek sealing and isolation product line.

"A pivotal point in our success came when we decided to create a one-stop experience for our customers," said Kris Beezley, senior vice president of Strategic Business Development with Lamons. "Rather than only producing gaskets, we expanded our product offerings to include standard and specialty fasteners, and hose assembly, which enabled us to provide total solutions for our customers."

Throughout the past seven-plus decades, Lamons has prided itself on continual improvement and innovation to better serve its customers and industries. A cornerstone in achieving this has been its philosophy of superior customer support worldwide with branch offices in North America, Europe, and Asia that provide quality products with faster service and on-time delivery.

Lamons CEO, Marc Roberts, suggested the company's focus on serving customers is what really sets the company apart from other suppliers (Figure 5). He noted that refineries and petrochemical plants could lose millions of dollars in revenue if a unit has to be kept offline for even a short period of time because it's waiting for a $20 gasket or a $5 bolt to be delivered. He knows the same is true for electric power generation plants.

"What we’ve really focused on is upping our service levels, such that we’re there 24/7, any day of the week, independent of whether it's a holiday or not—doesn't matter to us. We make sure that our customers will stay online and that our product is not going to be the impediment as to why they have a downtime issue," Roberts said.

Beezley said one of the buzzwords he's heard bantered about recently is "glocal," combining global and local. While he knows there are benefits to be gained in working with a global supplier, which Lamons is, there are also benefits to be captured from companies with a local touch that offer personalized service.

"People are looking for localized suppliers, and they’re looking for suppliers to be much more engaged in coming up with creative solutions around things like vendor-managed inventory, or VMI programs, for example. These can include managing consignment spares or looking at a partnership where we keep material on hand to help customers be more competitive," Beezley explained.

It's not a secret that supply chains have been challenged in recent years, mostly due to COVID-19, but also more recently due to sanctions on Russia as a result of the war in Ukraine. "A lot of material was coming from Eastern Europe and China," Beezley said. "All this has kind of morphed together, where, in order to keep up with the demand side, companies cannot continue having five- or six-month lead times in order to meet their production demands. I think it's shifted or pushed a lot of that requirement down to the sub-supplier in the supply chain market, and I think that's what has made Lamons much more relevant as a domestic supplier for the North American wind energy market, for example, and really for power generation overall."

"We manufacture 78% of everything that we sell worldwide here in Houston [Figure 6]," Roberts told POWER. "We are not a distributor. We are a direct manufacturer and directly sell to customers. In fact, we currently now sell to distributors."

"The industry has kind of pivoted here," Beezley said. "A couple of years ago, people were basically looking for the lowest cost. It was the only thing that mattered for a lot of people, which led them to suppliers in China or India or some of those locations. Now, it hasn't done a complete 180, but it has started to go in a different direction. People will pay a premium for better customer service or to have consignment or VMI programs. That wasn't really on the table two years ago."

For technical support and services, Lamons provides an array of offerings: custom engineered solutions, reverse engineering solutions, specialty machined parts, prototype machining, training, and field support. The company also employs a "Focused Factory" concept to ensure the most urgent orders get filled as soon as possible. Roberts said the concept has been used by the automobile industry for decades.

What Lamons has done is create a dedicated team that includes production workers (Figure 7), support staff, quality control team members, and others required to basically take an order and quickly produce a product that can be shipped in hours. Not every order is handled this way, but a certain percentage of orders come in with must-have-now stipulations, and those requests get this type of royal treatment. Roberts said the Focused Factory enhances Lamons’ ability to "service the customers when they need it, how they need it, and where they need it."

"I think most typical manufacturers have kept the first-in-first-out type of approach. It's like, ‘You give me a purchase order, and you’ll get what you want when I tell you the materials are ready.’ And I think a lot of people accept that because they don't think they have a choice," explained Beezley. "But our mentality is really what I’d call Johnny-on-the-spot. About 35–37% of our business is 24-hour turnaround or less. Close to 55% of our business is 48-hour turnaround. We figured out quickly how to have really dedicated machines and transportation, and very streamlined order entry systems, so that people can get the stuff that they need in a quicker fashion. And, honestly, I think that mentality plays extremely well for the power industry or any industry with time-sensitive requirements."

Lamons, a top supplier of custom seals and gaskets.