Neoprene Faced Phenolic Gasket Kit

Kaxite KXT-1002 neoprene faced phenolic gasket kits solve a specific problem in process piping: when two dissimilar metals are bolted together at a flange joint, moisture and electrolyte create a galvanic cell that corrodes the less noble metal. The fix is to break the electrical path — and the standard way to do that is with an insulating gasket and matching insulating sleeves and washers. This is a flange insulation gasket kit in the classic sense: a phenolic core for dielectric strength and mechanical support, neoprene faces for the compression seal.

The data below covers the standard KXT-1002 configuration. Non-standard sizes, flange ratings and complete kit contents (sleeves, washers, gasket) are quoted against drawing or drawing dimensions. Include the flange standard and class, gasket type (E or F) and quantity in the enquiry for accurate pricing and lead time.

The two standard configurations serve different flange access scenarios and isolation requirements. Choosing the wrong type either leaves part of the flange face unsealed or leaves the joint with no continuous isolation path.

Type E (full-face, left) and Type F (ring, right) — phenolic retainer core with neoprene sealing faces on both sides.

The two materials in the construction serve different functions and each is chosen for a specific reason. The laminated phenolic retainer provides dielectric strength — phenolic resin has high volume resistivity and high dielectric breakdown strength, which is what actually breaks the electrical path between the two flanges. It also provides mechanical support: the phenolic core carries the bolt clamp load without collapsing, holds the gasket thickness stable, and gives the kit its compression resistance. Phenolic alone, however, is not a good sealing material — it is hard and does not conform to surface imperfections.

That is where the neoprene rubber faces come in. Neoprene (polychloroprene) is factory-bonded to both sides of the phenolic core and provides the actual sealing surface. It conforms to flange surface imperfections under bolt load, has good resistance to oils, fuels, mild chemicals and water, and has adequate compression set resistance for the +80°C service range. The trade-off is temperature: neoprene's continuous service ceiling is around 80°C (175°F), which is why KXT-1002 is rated to that limit. Above this temperature, the phenolic core itself is not the limitation — the neoprene facing is.

For applications above 80°C, or for higher chemical resistance, alternative facing materials are available: PTFE-faced phenolic for higher chemical resistance at a slightly higher temperature ceiling, and the neoprene faced plain phenolic kit for configurations where a plain (rather than laminated) phenolic core is adequate. For higher mechanical strength and higher pressure class service, the SS316 core flange insulating gasket kit is the upgrade path — the stainless steel core carries higher bolt load and higher pressure than a phenolic core can support.

KXT-1002 is specified where dissimilar metal flanges meet and the joint must be electrically isolated to prevent galvanic corrosion. The dominant application is oil and gas pipeline flanges — wellhead connections, pipeline tie-ins, meter stations, pig launcher and receiver flanges, and compressor station piping — where carbon steel piping meets stainless steel valves, instrumentation, or dissimilar-metal equipment. In marine and offshore service, the kits are used at hull penetrations, seawater system flanges, and topside piping where saltwater electrolyte accelerates galvanic attack. In petrochemical plants, they isolate flanges between carbon steel and stainless steel pipe, or between stainless steel and high-alloy equipment. In municipal water and wastewater pipelines, they are used at transition points between coated steel, ductile iron and stainless steel components.

The use case is not limited to new construction. Retrofitting an isolation kit at an existing flange is one of the most common maintenance procedures when a corrosion inspection identifies galvanic attack at a dissimilar-metal joint. For this reason, the kits are supplied complete — gasket plus insulating sleeves plus insulating washers — so that the maintenance team does not have to source the sleeves and washers separately. For flanges that must meet specific isolation standards, the D-type configuration of the flange insulation kit range may be the more appropriate specification; see the Type D flange insulation gasket kit page for that variant.

KXT-1002 is manufactured at Kaxite’s Ningbo facility and supplied factory-direct for OEM, MRO, project and distribution procurement. Standard sizes are held for fast shipment; non-standard sizes, special flange ratings and complete kit supply (gasket + sleeves + washers, quantity-matched to the bolt count) are available against drawing or purchase specification. For buyers consolidating a flange isolation package, KXT-1002 can be combined with other flange insulation gasket configurations in a single shipment.