Spotlight On ...
The Origin ® APF-510 gaskets are produced from expanded PTFE tape with glass microspheres , resulting in an extremely compressible gasket that conforms to flange irregularities . To ensure a tight and reliable seal , a low porosity pure PTFE barrier is located near the gasket ID and under the pipe end to prevent permeation .
To test the design , TEADIT developed a rig using a MON- DI™ pressurized piping spool with two blind end flanges , one of which had a digital pressure gauge . The gaskets were installed as specified by the piping manufacturer . To simulate flange damage , a small hole was drilled through one of the flanges . After assembly and pressurization , the rig was submerged in water and evaluated for signs of leaks ( i . e . bubbles ) and the internal pressure was monitored for 48 hours . A second penetration test was performed utilizing the same rig filled with red dye and pressurized to twice the original pressure .
The Origin ® APF-510 showed extremely favorable results in both lab tests . No visible signs of leakage were observed , and the final pressure loss after 48 hours was less than 0.5 psi . Additionally , the dye penetrant test clearly showed that no permeation occurred beyond the barrier layer .
Origin ® in Glass-Lined Equipment
Another excellent application for Origin ® technology is glass-lined equipment . Glass lining is popular in tanks and other vessels used in aggressive services . Obviously , great care must be given to prevent damage to the fragile glass lining . This means that connections to glass-lined vessels require limited clamping force to ensure that developed stresses do not exceed the glass ’ s capacity , resulting in cracks . Another challenge with glass-lined equipment is the inherent waviness in the mating surface . On large vessels , it is not uncommon to see variances as large as ¼ ” or more .
Many glass-lined vessel OEMs utilize PTFE envelope gaskets which consist of a thin virgin PTFE outer jacket ( or envelope ) with , typically , two layers of a low-quality fiber material with a corrugated metal ring in between , used for filler . These gaskets are then shimmed when installed to compensate for gaps .
PTFE envelope technology is dated and comes with many known issues , the greatest of which is the PTFE envelope itself . As virgin PTFE exhibits a high level of cold flow , it is possible to over-compress and cut through , or otherwise damage , the thin outer shell of the gasket . When this happens , the inner filler materials , none of which are compatible with the aggressive
services most glass-lined equipment handles , are exposed to the process media , and leaks quickly occur . Additionally , envelope gaskets exhibit poor recovery .
Origin ® technology , on the other hand , exhibits excellent recovery characteristics . For example , the Origin ® RC-510 railcar tank manway gasket was tested for over 40 open-close reuse cycles with no loss in sealing performance .
Another benefit of Origin ® technology is that the gaskets can be manufactured in almost any thickness . Traditional gasket materials typically max out at ¼ ” thickness . In some cases , such as in high spots where the glass aligns , this could result in face-toface contact with the mating surfaces and damage to the glass lining . If , on the other hand , large gaps exist , the ¼ ” thick material may not be enough to fill the gaps ; traditional gasket materials are not able to be easily or effectively shimmed .
Soft and compressible materials are sometimes used to replace PTFE envelope gaskets on glass-lined equipment . However , ‘ soft ’ in the gasketing world often indicates that a material is more porous and susceptible to wicking through the body of the gasket . Again , the option to include a pure PTFE barrier layer , like that which is used in the Origin ® APF-510 gasket , has shown proven resistance to permeation .
Origin ® technology gaskets are highly compressible and will easily conform to the conditions of the mating flanges in glass-lined equipment . It is designed to ensure a positive seal at low tightening loads on deformed surfaces . By filling any gaps and molding to the sealing surface , it creates a tighter and more reliable seal .
Teadit at a Glance
TEADIT Group is recognized worldwide as a leader in the development and manufacturing of innovative products for critical fluid sealing processes . The wide variety of sealing solutions developed by TEADIT have been important tools for many industries including Oil & Gas , Chemical Processing , and Power Generation . TEADIT has helped several industries achieve the goal of an emission-free environment within their facilities . TEADIT is constantly investing in research and development to keep up with the evolution of the industry ’ s needs .
TEADIT North America is located in Houston , Texas with seven worldwide locations in South America , Europe , and Asia . The variety of sealing solutions developed by TEADIT is fundamental to achieving the leakage-free goal in the many industries served . The quality and effectiveness of these solutions are based on management and innovation , which are the basis for all products manufactured at any TEADIT plant . As a result of this continuous process of quality improvement , an ISO 9001 certification was obtained in Brazil , the United States , and Europe .
The 64-year history of TEADIT began in Rio de Janeiro and has led to more than twenty patents on products and processes . Their corporate values of Integrity , Reliability , Safety , and being Customer Focused and all culminate in their vision statement : Sealing For A Safer And Greener Tomorrow .
In Conclusion
The uses for Origin ® technology are nearly as limitless as the possible configurations that it can be made to . MONDI™ piping , glass-lined equipment , and railcar manways are just a few of the many successful uses TEADIT and its knowledgeable team of product experts and engineers have found thus far . In many ways , the company is just scratching the surface of what it can do with this innovative technology .
Even in general services , as a replacement for traditional cut gaskets , Origin ® technology offers several distinct advantages . EN13555 testing shows favorable results when compared to modern structured PTFE , like Teadit Tealon and similar competitor materials . Additionally , the manufacturing process allows for one-piece gaskets larger than the maximum outside diameter of sheet-cut gaskets which are limited by the commonly available square sheet size of around 60 inches .
The views and opinions expressed in this article are those of the profiled company and may not reflect the position of Stainless Steel World Americas .
Stainless Steel World Americas - August 2023 | www . ssw-americas . com 3