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
GYLON EPIX™ is a newly developed family of PTFE gaskets. It is manufactured using a patented, profiled surface based on Garlock's proven Fawn, Off-White, and Blue GYLON® to create highly conformable materials for optimum sealing performance.
GYLON EPIX™ provides superior functional performance by combining the traditional attributes of GYLON® with an innovative surface design. It offers a broader range of applications than traditional PTFE gaskets that are used in worn and pitted flanges. In addition, this evolutionary material
The customer’s chemical treatment vessel has nonstandard rectangular flanges with a limited number of bolts. The limited bolting resulted in inadequate compression to seal the gasket and the non-standard shape made the use of a molded engineered gasket unfeasible. When tested, expanded PTFE leaked. There was no alternative known at that time so the mess of crystalized leaking media was accepted as normal.
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 EPX 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.
GYLON® Style 3522 gasket is made of 100% pure PTFE with no fillers or additives, making the material ideal for the most demanding, high purity requirements. Industries such as food, pharmaceutical, semi-conductor, recognize the uniformity of GYLON® 3522 that makes it an ideal gasket choice for those critical applications that cannot risk process contamination or premature failure.
Bolted flange-gasket connections in process piping systems are common and given little thought – unless they start to leak.
Chronic leakage proved to be an issue for one of Garlock's clients, a midstream oil and gas processor and services provider. The site processes, stores, and transports natural gas, liquefied natural gas and petroleum products. Garlock was brought in to provide a solution to the problem.
Successful connections are dependent on a variety of things, including the state of the flange surfaces, alignment, bolt and nut grade and strength, bolt and nut thread condition, lubrication, bolt tightening process, service conditions, and choice of gasket.
When a flange-gasket joint is assembled, the gasket must first be compressed to fill the gaps between the flange surfaces, creating a seal when system pressure is applied. Secondly, it must maintain that seal as the system is brought on-line and temperature and pressure escalate.
As the temperature increases, a gasket made of non-metallic materials such as rubber, fibre, PTFE and inorganic fillers is prone to lose thickness, that is, creep. And the thicker the gasket is, the
more it is prone to creep (1/8-inch thick gaskets creep more than 1/16-inch).
The two most important performance qualities of a gasket are its ability to seal and its ability maintain that seal. These can be indicated by industry standard tests for sealability and creep.
On the surface, this particular case study would seem to be an application of little complexity. However, the details of the joint gave rise to several issues that caused the user chronic leakage problems. Here are the service conditions and background of this particular case:
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
Chemical Manufacturer and Distributor
Loading stations are very critical in the chemical industry as flanges are disassembled and reassembled everyday.
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
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:
From those answers, Garlock drew the following conclusions, representing the most desirable and essential PTFE gasket characteristics:
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:
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.
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