Piping Flange Isolation Kits and Gaskets
GPT flange isolation(insulation) products are constructed of premium engineering materials. The isolation products include a wide selection of isolating/sealing gaskets along with a variety of sleeves and washers. For maximum flexibility, components may be ordered separately or as part of complete flange isolation kits (FIK).
Flange Isolation Kits are designed to work in conjunction with our isolating gaskets to effect the complete electrical isolation of a flanged assembly. The Isolation Kits consist of one full-length isolating sleeve, two isolating washers and two steel washers for each of the bolts in the flange assembly. The purpose of the isolating sleeves is to electrically separate the bolts from each side of the flange, while the isolating washers provide electrical isolation for each of the nuts attached to the bolts. This method of isolation provides the user with a high-reliability solution to complete the electrical isolation of a flanged joint.
The Pikotek® VCS® gasket provides exceptional insulating and general sealing performance in aggressive material applications. The VCS gasket is suitable in all services up to and including ANSI 2500# and API 10,000# classes.¹
Due to its unique pressure activated sealing mechanism, the gasket requires far less bolt stress to seal than any other gasket.² The VCS gasket inner diameter is exactly matched to the flange bore to eliminate turbulent flow and flange face erosion/corrosion. The seal elements are replaceable in the reusable gasket retainer.
¹ As per design review. Please contact GPT product engineering for further information.
² Please see GPT Torque Calculator
The VCXT™ high temperature flange insulation sets create a seal and maintain electrical isolation across a wide range of seating stresses and flange classes in elevated temperature service. They can be used in load compromised connections; such as damaged and/or lined flanges and also heavily bolted connections where significant gasket stresses may be generated.
The insulating gaskets and washers have been designed and developed for use in standard pipeline flanges where both cathodic protection and high integrity sealing are required at elevated service temperatures. For non-standard bolted connections please consult your regional GPT sales manager.
The VCS-ID® (Inside Diameter) Seal introduces an internal, machined PTFE seal at the bore of the existing VCS design platform. The use of a patented interlocking mechanism ensures an extremely tight seal at the bore and resistance to effects from internal pressure or aggressive media. The interlocking mechanism is intentionally designed to be approximately 0.100” larger than the pipe ID.
During installation/loading, the interlocking mechanism will compress to a final state that is slightly larger than the pipe ID. This reduces cavitation in the piping, reduces flange erosion and helps prevent microbiologically induced corrosion (MIC), while not affecting any line pigging operations.
Additionally, the PTFE interlocking mechanism creates a longer effective isolating distance than the standard platform.Traditional VCS gaskets leave the steel core exposed to the media. This increases the likelihood of the formation of an electrically conductive bridge between the flange face and steel core of the gasket, especially if the media contains conductive particles that lead to sediment build-up in the pipeline. Because the thickness of the inner PTFE seal is the same as the gasket thickness, the formation of an electrical bridge caused by conductive sediment build-up between the gasket steel core and the flange face is eliminated. Further, PTFE is not hygroscopic, so it does not have a tendency to absorb water, making it even more attractive as front line defense in electrical isolation. This unique design helps solve problems where hydrotested lines may no longer isolate.
Our patented interlocking mechanism is “dual locking” to provide a secure seal that won’t dislodge during handling, transport or installation. The “dual locking” feature creates a positive lock in both vertical and radial directions.
The interlocking mechanism also eliminates the need for exotic metal gasket core material because it breaks the metal-to-metal path. Obtaining exotic metals can cause long lead times and extra expense that are eliminated with the use of a VCS-ID seal.
Another benefit of the VCS-ID seal is that PTFE doesn’t have an affinity for water absorption, installations where electrical isolation testing is performed shortly after hydro-test are less likely to be c orrupted.The VCS-ID does not require any more torque than the standard VCS or VCFS, making installation simple using the same specification charts.
The PGE™ was designed to give operators an alternative to the failure prone phenolic-based isolating gaskets. The unique design of the PGE™ system incorporates patented overlapping and offsetting seal grooves. The purpose of this design is to break each layer of laminate within the gasket itself, thereby creating a barrier through which fluid and/or gas cannot migrate. The sealing element can be any elastomeric material, as well as more sophisticated spring-energized PTFE lip seals. As a result of this advanced seal design, maintenance-free flange isolation and flange face corrosion mitigation are achieved economically. Depending upon the sealing element selected, the PGE™ is rated for most hydrocarbon and water service applications.
This gasket is suitable for use in raised-face and flat-face flanges in ANSI Class 150, 300 and 600 service¹ (or equivalent). In addition to providing electrical isolation, the gasket is excellent for isolating flanges made of dissimilar metals or where prevention of flange face corrosion is desired.
NSF/ANSI Standard 61 establishes minimum health effects requirements for the chemical contaminants and impurities that may be indirectly imparted to drinking water. The LineBacker® 61™ Sealing/Isolating gasket is certified to conform with all criteria associated with NSF health effects testing, certification and production facility inspections.
Of particular importance with respect to NSF/ANSI Standard 61, is the micro-exposure of the sealing element (EPDM) within the G-10 Epoxy Glass retainer material. In addition to providing positive sealing characteristics relative to the fluid flowing in the pipe, the sealing element is also fully encapsulated between the flange and GRE retainer, reducing exposure of the sealing element to harsh outside atmospheric conditions.
For more information regarding NSF, please contact GPT Engineering.