In a brine concentrator, an original competitor’s expansion joint failed upon start up.
Background of the Facility:
This facility is a Zero Liquid Discharge (ZLD) power plant. Water is initially pumped from a well, pre-treated, used as process water, then reclaimed and retreated with a Brine Concentrator for use in their cooling towers. No city water is used and no waste water is disposed of from the site.
Brine concentrators use thermal energy to evaporate water, which is subsequently condensed and discharged as clean distilled water.
Brine Concentrators are also used in water treatment facilities in desalination plants, mining operations and well drilling operations in the oil & gas industry.
Size: 24 “x 10” FF
Temperature: 221° F
Media: Brine Slurry
Pressure: 30 psi
The original expansion joint unfortunately failed catastrophically without warning on start up. After consultation with the OEM of the Brine Concentrator, the recommendation was that only Garlock Expansion Joints be used for this aggressive application. The original expansion joints were replaced with Style 206 expansion joints which are built with a 4 to 1 safety factor.
Upon start up, Garlock Style 206 expansion joints offered superior performance, reliability and service life. This in turn improved plant safety, increased the mechanical integrity of equipment, and allowed Garlock’s customer to gain a competitive advantage in the market place.
The original article was featured on Garlock’s website and can be found here.
Gallagher Fluid Seals is an authorized distributor of Garlock gaskets, packing, expansion joints, and more.
GYLON EPIX® is a family of gaskets that effectively seals a broader range of applications and is more forgiving during the installation process. It allows the end user to save valuable turn-around time, reduce re-work, and lower costs, helping them to finish ahead of schedule and under budget.
GYLON EPIX® features a hexagonal surface profile that provides the torque retention and blowout resistance of a thin gasket and the conformability of a thicker gasket. GYLON EPIX Style 3504 is a high performance, aluminosilicate microsphere filled PTFE sheet material designed for use in moderate concentrations of acids, and caustics, as well as hydrocarbons, refrigerants, and more.
Chemical Manufacturer and Distributor
Loading stations are very critical in the chemical industry as flanges are disassembled and reassembled everyday.
Due to the dangerous media being transported through the flanges there is a high risk of incidents and human harm, making it necessary for the gaskets to only be used once. For this reason the customer was looking to evaluate a solution that was more adaptable than the current gaskets being used.
Temperature – Ambient outdoor temperature
Application – Flange connections at the load/unload station (4 stations). Flanges EN1092-1 Type 01, PN10-40, 316 TI stainless steel
Media – Sulfuric Acid (Oleum) with a concentration of 94%
Pressure – 2 bar/29 psig
SOLUTION AND BENEFITS
GYLON EPIX 3504 PTFE gasket with Aluminosilicate Microspheres is specifically designed for use in applications where many acids and caustics are present, making it the ideal solution in the loading stations. GYLON EPIX 3504 performed exceptionally during the 110 day evaulation allowing the customer to continue use with confidence.
Gallagher is your source for all of your Garlock sealing needs. If you have further questions regarding the GYLON EPIX™ 3504 EPX, or any other Garlock products, please do not hesitate to contact us. Our engineering department is always ready to help you design a sealing solution to your toughest application!
The Style 204 family of spool-type expansion joints are manufactured with the industry standard narrow arch design. This style is intended to be used in dynamic conditions where both pressure and vacuum concerns are present.
Features and Benefits
Fully laboratory and field tested for long life and exceptional reliability
High pressure and vacuum resistance offer increased safety and ensure suitability for a wide range of applications
Single and multi-arch designs are available for a range of movement capabilities
Concentric and eccentric reducing configurations can be provided to join piping of unequal diameters
Available in a variety of elastomers and fabric combinations to meet the varied demands of temperature, pressure, and media
Pulp and Paper
Large South Eastern Paper Mill
A U.S. paper mill experienced multiple failures of expansion joints on the knotter screen pumps in the fiber area of the plant. The failures caused significant downtime and posed a safety hazard to employees working in the area.
Size- 24”ID (DN600)
Temperature- Less than 250°F (120°C)
Application- Knotter screen feed pump
Media- Black liquor with wood fiber
Pressure- Less than 65 psi (4.5bar)
A field survey determined that the expansion joints were experiencing significant elongation during installation. It was also evident that the pump and pipe flanges were not in parallel, creating angular misalignment. Additionally, the expansion joints were handling an aggressive media of black liquor and wood fibers, which collectively contributed to the failure.
SOLUTION AND BENEFITS
Through on-site troubleshooting and surveying of the expansion joints, engineers were able to recommend and design an adapter plate for the pump flanges to realign the pump to the piping. This allowed the plant to standardize the replacement expansion joints to Style 204 with GUARDIAN® FEP liner to be used in multiple locations. In addition, the mechanical bond of the GUARDIAN® FEP liner provided greater reliability than the adhesive bond of competitive PTFE lined expansion joints. Replacement cost and frequency has been significantly reduced as a result of this engineered solution.
The original case study can be found on Garlock’s website here.
Gallagher Fluid Seals is an authorized distributor of Garlock. For questions about products or to learn more about rubber expansion joints, contact our engineering department.
Bacteria accumulation can ruin product and put consumer health at risk.
Bacteria accumulation is a serious issue in the food manufacturing industry – it can ruin product and put consumer health at risk.
While many know that Polytetrafluoroethylene (PTFE) is an excellent choice for use in diaphragms and gaskets, most do not realize that there exist varying grades of PTFE. Some lower cost PTFE offerings may contain an excessive volume of pores within their structure which can harbor organic contaminants such as bacteria.
To address this problem, a calendared manufacturing process is used. Calendared PTFE is a premium grade PTFE designed for use in aseptic applications requiring ultra-high purity standards. It is ideal for use in food, pharmaceuticals and a variety of clean markets.
Distinguished by an extremely low void content, calendared PTFE resists permeation and the accumulation of foreign matter, reducing the risk of harboring unwanted bacteria or residual media.
To achieve this, the unique manufacturing process orients the chains of PTFE in a lattice-like structure that reduces voids in the material and provides it with biaxial strength. This unique structure also delivers a very high flex life. When tested in an MIT Folding Endurance Tester, the flex life of calendared PTFE is four-times greater than conventional PTFE materials.
Unlike the skived process that is commonly used for PTFE manufacturing, the calendaring process produces uniform sheets of material with consistent physical properties. This gives calendared PTFE a renowned reputation for predictable performance and quality. The opposite is true for skived PTFE where variable properties lead to varying performance and reliability.
Gylon Epix’s patterned material provides enhanced compressibility for better sealing
Gaskets are ubiquitous components in a processing plant. Every flange, equipment joint and connection point will have some form of gasket to prevent fluids from compromising (i.e., leaking from) a process system. However, effective sealing can pose challenges. A new form of polytetrafluoroethylene (PTFE) gasket, Gylon Epix, already has successfully addressed a number of persistent problems at plants.
The gasket, which is available in 3⁄32-in.-thick, 60-in. × 60-in. sheets, features a raised hexagonal pattern (Figure 1). It exhibits enhanced compressibility over both 1⁄16-in. and 1⁄8-in. traditional gaskets, seals easily when compressed by flanges and maintains assembled bolt torque better than comparable 1⁄8-in. PTFE gasket materials.
Successes with Gylon 3501-E and Gylon 3504
Trials at three early adopters of the new material underscore its value.
Fatty acid production. A German manufacturer of oleo-based chemicals, including fatty acids, glycerin, fatty alcohols and fatty esters used in consumer and personal health products, was experiencing problems sealing a 29.3-in. (745-mm) outside-diameter spiral heat exchanger. A gasket located atop the heat exchanger was exposed to polysaturated fatty acid and coolant at a continuous temperature of 428°F (220°C) and pressure of 87 psig (6 bar). J-type clamp bolts fasten the lid to the heat exchanger. Spiral heat exchangers present challenges because the gasket must seal across the entire face of the lid, requiring a gasket that will efficiently transmit the force from the bolts across its entire surface.
The traditional PTFE sheet gasket was allowing leakage across the exchanger’s spiral passes, decreasing efficiency. The gasket exhibited cuts from the spiral separation bars and required frequent changes that disrupted manufacturing and decreased plant productivity.
Gylon Epix 3501-E was installed in December 2017 and, after six months of testing, concluded it sealed well. Upon disassembly in July 2018, it was found to be in good condition, with no traces of cuts, discoloration, brittleness or sticking to the lid (Figure 2). A new gasket was installed in July 2018, which now has completed a successful one-year trial; the gasket continues to perform well.
Phosphate processing. New or refurbished equipment generally seals bolted connections well. As the equipment ages, gaskets and flange surfaces help seal gaps caused by corroded, worn, misaligned or repositioned equipment flanges. At a Mexican acid processor, Class 150, 8-in. raised-face flanges of the inlets and discharges of phosphoric and sulfuric acid transfer pumps had become worn and corroded. Temperatures were 104°F (40°C) and pressures 57 psig (4 bar). The 1⁄8-in.-thick glass-filled PTFE gaskets didn’t consistently provide a tight seal. So, the plant applied mastic filler to treat damaged flange surfaces as a stop-gap measure.
Gylon Epix 3504 was installed in December of 2017; it performed successfully without the need for flange treatments or special installation handling. Its enhanced compressibility fills the gap of imperfect flanges. It performed well until its removal in September of 2018 when the pump mechanically failed for a reason not related to the gasket. The acid processor is adding Gylon Epix to its approved materials list because it worked without the need for mastic, was flexible and easy to handle, and performed with zero leaks.
Terephthalic acid manufacturing. A southeastern U.S. producer of terphthalic acid (TPA) was experiencing leaks with traditional glass-filled PTFE sheet gaskets on a pressure vessel operating at 230°F and 60 psig that has a 60-in. × 10-in. rectangular gasket joint opening. Large rectangular joints can have uneven surfaces due to warpage of the cover. In July of 2018, Gylon Epix 3504 was installed and is still in service as of September 2019 and performing well. The company has accepted the product into its system and is re-ordering.
The original article can be found here and was written by Jim Grago, PE, a principal applications engineer for Garlock.
Gallagher Fluid Seals is an authorized distributor of Garlock. For questions about products or to see if Gylon Epix is the right fit for your application, contact our engineering department.
Enhancing the surface profile can improve sealing capabilities, extending the functionality of aging piping systems in chemical plants.
There are many aged and aging process plants in operation today. In fact, many of the processing plants for power, chemicals, oil, etc., have been in service for more than 50 years. And while the piping itself may remain intact, their bolted flange gasket joints and connections are becoming misaligned, corroded and damaged due to repeated handling, chemical exposure and thermal cycling. This can lead to costly ruptures that may result in millions of dollars in damages, downtime, noncompliance penalties, irreparable environmental impact and litigation.
There is a solution that can extend the life of aging piping systems, preserving their functionality: raising the surface profile on polytetrafluoroethylene (PTFE) gaskets. This design modification can prevent leaks, spills and other releases in chemical processing plants by reducing and managing the contacted area of the gasket, thus achieving and maintaining a strong seal.
A Brief History of Gasket Technology
Traditionally, gasket thickness and sealability always involved a performance tradeoff. One could use 1/16-inch-thick (1.6 millimeter) gaskets when flanges were in good condition, achieving a tight seal with reduced creep.
However, when the flanges had bad or misaligned surfaces, the seal integrity was degraded.
In those instances when the flanges are in poor condition (or if the shape of the flange condition is unknown), one would choose a 1/8-inch-thick (3.2 mm) gasket. The reason? A user does not want to risk installing a thinner gasket and discover that it does not seal properly, which then requires a timely and costly uninstall and reinstall. However, the thicker gaskets do not seal as well as their 1/16-inch counterparts when placed under comparable load. Additionally, with the thicker gaskets, creep is higher, requiring re-torque.
To address the limitations of both gasket options, the ideal gasket should combine the creep resistance of a 1/16-inch gasket with the compressibility and conformability of a 1/8-inch gasket—easier said than done.
Historically, gaskets have not always been forgiving, easy to use or simple to remove. Yet technology has evolved, allowing sealing products to be engineered and designed to optimize the work that is put into them, delivering a tighter, more durable seal.
The approach is one that does not focus on the gasket thickness but rather its surface profile. The results produce gaskets that reduce leaks, spills and other releases from piping systems, including those of aging chemical plants.
Raising the Gasket Profile
The concept of using surface profiling to reduce area and increase stress is found in many products, such as running shoes and car tires. Reducing the contact area while maintaining a given amount of compressive force results in increased stress. In the case of shoes or tires, this stress provides traction. In the case of gaskets, traction or friction between a gasket and a flange face is critical to holding internal pressure. If the downward force created by the fasteners in a flange is evenly spread over a larger area, the created stress contributes to making a seal more effective. This approach enables the aging piping system to maximize its sealing potential.
Impact on Raising Gasket Profile
Surface profiling positively impacts gasket technology in five key areas: compressibility, pressure resistance, scalability, load retention and dimensional flexibility.
Compressibility is a critical functionality of gaskets, as it represents the ability of the gasket to conform to the surfaces that it seals. Adding raised features to the surface of a gasket directly impacts compressibility by reducing the contact area and increasing the resulting stress.
When flange surfaces are worn, pitted or scratched—such as those in aging piping systems in chemical plants—it can be cost prohibitive and nearly impossible to repair/replace the flange to a “good as new” condition. The more compressible the gasket, the better chance of producing an effective seal with the flanges. Continue reading Raising the Gasket / Surface Profile in Aging Systems→
The search for the ideal Polytetrafluoroethylene (PTFE) gasket has been elusive. Competing applications and workplace variables have led to the creation of myriad solutions, yet none that has proven fully adaptable and appropriate for universal adoption.
Garlock Sealing Technologies considered this to be a critical yet entirely solvable shortcoming. And it is against this backdrop that in 2016, they set out to compile a comprehensive list of attributes for the ideal PTFE gasket — a wish list, as it were — in order to build a better gasket.
Working with a third-party survey development company, Garlock developed an exhaustive questionnaire that probed every aspect and functionality of PTFE gaskets, testing and adjusting the questions until they had a workable, finalized version.
Using this final questionnaire, Garlock conducted extensive interviews at 15 major chemical processor companies, speaking with 20 engineers responsible for process operations, projects, maintenance and reliability. The goal was simple: to discover the ideal characteristics and their relative importance that engineers sought in a PTFE gasket.
After several months of data collection, Garlock analyzed the feedback and noted the most popular responses:
28% of respondents said that they struggled with how different gaskets required different compressive loads and how to ensure that those gaskets had been installed properly
21% expressed frustration with the creep properties of PTFE gaskets
21% desired a gasket that seals with less compressive load
14% expressed frustration at the installation inconsistencies of their fitters
14% expressed frustration with leaking, especially after a successful installation and start-up
From those answers, Garlock drew the following conclusions, representing the most desirable and essential PTFE gasket characteristics:
Seal: Seals easily
Installation and assembly: Forgiving of poor installation or assembly practices
Forgiving: Forgiving of poor flange conditions
Retention: Maintains a seal after installation
Flexible: Can be used in a broad range of services to avoid user confusion and reduce inventory
Introducing: GYLON EPIX
Garlock used this feedback in developing a next generation PTFE gasket — GYLON EPIX. Featuring a hexagonal surface profile, GYLON EPIX offers superior compressibility and sealing for use in chemical processing environments. Its enhanced surface profile performs as well or better than existing 1/16″ or 1/8″ gaskets, allowing end-users and distributors to consolidate inventory, lower the risk of using incorrect gasket thicknesses and reduce stocking costs.
GYLON EPIX checks off the most desirable gasket attributes:
Installation and assembly: Even distribution of the bolt load over the contacted area of the gasket during the assembly process
Retention: Retention of the bolt load administered at assembly
Seal: Efficient translation of bolt load to sealing performance
Forgiving: The ability to perform in imperfect flanges and installation conditions
GYLON EPIX with its raised, hexagonal profile allows it to perform the job of both traditional 1/16” and 1/8” gaskets. It accomplishes this by combining the bolt retention of the former with the forgiveness for bad flange conditions of the latter, a truly innovative feature for PTFE sheet gasketing. Continue reading The Ideal PTFE Gasket for Tough Applications – GYLON EPIX→
FLOOD-GARD Offers Bearing Protection in Challenging Flooded Environments
Garlock has launched FLOOD-GARD Bearing Isolators for flooded applications. The patent-pending seal design provides bearing protection even in the most challenging flooded environments, extending the life of rotating equipment such as gearboxes, pumps, and motors.
“FLOOD-GARD™ allows Garlock to unlock value for our customers by taking industry leading bearing isolator technology, and advancing it even further, into a seal that excels in flooded conditions,” says Kevin Allison, Product Manager, KLOZURE®.
The latest addition to Garlock’s family of KLOZURE® Bearing Isolators, FLOOD-GARD™ is a revolutionary seal that combines improved safety and overall process efficiency with cost savings through extended equipment and bearing life. FLOOD-GARD’s Cam-Lock design provides excellent bore retention while allowing easy installation by hand, without the need for an arbor press. Other benefits include the ability to accommodate up to .015” of radial shaft misalignment and patented PTFE unitized construction that eliminates metal-to-metal contact, all while achieving an IP66 rating in most configurations — flanged, small cross section, step shaft and vertical.
Patented seal design provides bearing protection even in the most challenging flooded environments, extending the life of rotating equipment
Rugged, unitized construction for ease of installation
IP66 in most common design configurations
Available in standard and small cross section configurations
Substantially reduced installation time – NO ARBOR PRESS NEEDED
No metal-to-metal contact between stator and rotor
Handles up to .015″ of misalignment
FLOOD-GARD™ allows Garlock to unlock value for our customers by taking industry leading bearing isolator technology, and advancing it even further, into a seal that excels in flooded conditions.
Recent gasket failures in flanged joints of High Density Polyethylene (HDPE) piping.
HDPE piping joints are typically thermal fusion welded joints, but flanges may also be used. When flanges are used, an HDPE flange adapter with a metal backing ring is fused to HDPE piping, as shown in Figure 1. The HDPE flange adapters are used to connect to other flanged fittings, such as valves, elbows, tees, etc., with gaskets inserted between the flanged fittings.
In 2018, two HDPE flange adapter gaskets on two different valves that were part of an underground fire suppression system at a Department of Energy (DOE) nuclear facility in Amarillo, TX failed, causing several weeks of unplanned interruptions to nuclear facility operations. Fire suppression water was isolated to two nuclear facilities, requiring nuclear operations to be paused and fire watches to be established. Both couplings were installed by the same contractor and had been in service for approximately eight years. Both flanges were correctly torqued to 160 foot-pounds with no indication of the necessary re-torque. The initial failure of the gasket caused a low flow, high-pressure leak that was not detected for some time. With the system pressure operating at approximately 150 pounds per square inch (psi), the orifice created by the failure of the gasket(s) between the two flanged faces created a water jet, which eroded the metal valve flange and bolts.
Because HDPE will relax after the flange bolts are torqued, a re-torque after 24 hours is required. Even after the bolts are re-torqued, the face stresses drop to 400–600 psi. The lower face stress reduces the friction for maintaining the gasket in between the flange faces. The challenge is finding a gasket that can handle pressures that may exceed 200 psi, gauge (psig), but also seal well at relatively low stresses.
Due to the many inquiries from customers and engineering firms for gasket applications involving HDPE piping, Garlock, a gasket manufacturer, published a memo in January 2017 recommending using either GYLON® Style 3545 or MULTI-SWELL™ Styles 3760/3760U as the best options for HDPE flanges, even though the available compressive loads are lower than recommended. The reinforced gasket material of the GYLON and MULTI-SWELL has proven to prevent the internal water pressure from damaging the gasket under low-compression loads.
Other gasket manufacturers may have similar gaskets that will work for this application. It is important for the Design Engineer to work with the gasket manufacturer to properly specify the correct gasket.
Recommendations to HPDE Piping and Flanged Joints
When using HPDE piping with flanged joints, ensure that the flange bolts are re-torqued at least 24 hours after gasket installation.
When evaluating gasket material, be sure to include any surge pressure that could be caused by opening valve and starting pumps. Also, include any additional design/safety factors in your gasket calculation. And, directly work with the gasket manufacturer in making a selection.
Rare and Ultra-Pure Resources Present Unique Challenge to Finding Appropriate Low Temp Gasket
Modern technology often requires rare or ultra-pure materials that can only be handled or obtained within extreme environmental conditions. These same conditions present unique and hazardous difficulties when transporting or utilizing these resources. Resources such as liquid oxygen, nitrogen, or argon; all of which are classified as “industrial gases” are handled well below the normal temperature ranges that every-day liquids exist; ranging as low as -195.8°C (-320.4°F). This often makes it a challenging task to find a low temp gasket to fit the specifications for the application.
As an example, let’s look at argon; an important gas used in Welding, Neon Lights, 3D Printing, and Metal Production, just to name a few. It is far more economical to house and transport argon in its liquid state. However, it must be held at an astonishingly low -185.9°C. Fitting the pipes together and maintaining a seal in a cryogenically engineered system that the liquid argon is housed presents unique difficulties. Argon gas is colorless, odorless, tasteless, and can irritate the skin and the eyes on contact. In its liquid form it can cause frostbite.
There are important considerations that should be taken into account when installing gaskets for dangerous extreme low temp materials.
Proper Gasket Installation
Many gasket materials can become brittle, crack, shrink, and blow out when exposed to extreme cold – not something you want to happen at any time, let alone with a liquid that can freeze you into a meatsickle. So, proper installation is also key. During installation, it is important that all parts are dry, the installation is done at ambient temperature, and then re-adjusted with changes in temperature.
Any mechanical seal that is sealing a product with a temperature below 0 degrees Celsius is given the name “Cryogenic”. Liquefied gases (LNG), such as liquid nitrogen and liquid helium, are used in many cryogenic applications, as well as hydrocarbons with low freezing points, refrigerants and coolants.
When selecting a low temp gasket or sealing material to be used in cryogenic service, it is important that the material can withstand cryogenic temperatures.
Low temperature applications are found across many industries, these include:
Garlock GYLON® and KLINGER SLS/HL
Good gasketing materials that can withstand the frigid cold and are pliable in the requirement to maintain the seal would be the Garlock GYLON family of gaskets (PTFE, capable of -450°F (-268°C)) or the Klinger SLS/HL, which is made of flexible graphite and can withstand -400°F (-240°C)
As with all gasket applications, environmental conditions should be considered in conjunction with the functional requirements of the device. Though there are limited options to solve extreme low temp gasketing challenges, Gylon and Klinger can be a good fit for your application.
Portions of the original article were written by Michael Pawlowski and Sylvia Flegg of Triangle Fluid Controls Ltd. The article can be found on Empowering Pumps website here.