Kaxite double jacketed gasket is a soft-core gasket wrapped in a metal jacket. The metal jacket protects the core from the process fluid and provides the rigidity needed on flat face and raised face flanges; the soft core provides the conformability a metal-only gasket cannot. The jacket fully or partially encloses the core, and partition bars can be integrated or welded into the gasket for heat exchanger pass partitions. This is the gasket that makes heat exchanger channels, boiler flue ducts, pump casings, gas mains and valve bonnets seal reliably when the flange faces are wide and the media is corrosive. See the wider range on the double jacketed gaskets parent page.
The bar is formed from the same jacket metal and pressed into the gasket during stamping. Fast to produce, suitable for small to medium pass bars where the bar stays within the gasket outline.
A separate jacket-metal bar is welded across the gasket face. Used for long pass bars, multiple passes and heat exchanger channel covers where the bar must transfer load between flanges.
The thickness is held to a one-sided negative tolerance so the gasket never exceeds its nominal thickness on the bolts. On a heat exchanger channel with a long bolt circle, a 0.8 mm oversize gasket would change the bolt load distribution across the pass bars, so this tolerance is not a marketing claim — it is a fit requirement. The OD/ID tolerance is also one-sided negative, matching the ASME B16.5 flange bore so the gasket never sits proud of the raised face.
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| Dimension | Tolerance | Applies to |
|---|---|---|
| Gasket thickness | +0.8 mm / -0.0 mm | All sizes |
| Outside diameter | +1.5 mm / -0.0 mm | NPS 1/2 – NPS 24 |
| Inside diameter | +1.5 mm / -0.0 mm | NPS 1/2 – NPS 24 |
| Partition bar thickness | Matched to gasket | Per drawing |
| Bolt-hole pitch | Per ASME B16.5 flange | Standard flanges |
Non-standard sizes are quoted from drawings. For very large exchangers or non-circular shapes, Kaxite will issue a dimensional drawing before production; the customer signs off the drawing before material is cut.
The jacket and the core are chosen as a pair. A 316 jacket with graphite core is the default for steam and hydrocarbons; a 304 jacket with PTFE core suits acids and solvents up to 260°C; a stainless jacket with ceramic core handles boiler flue and high-temperature service. Send the media, temperature and flange material and Kaxite returns the pair.
These are ASME B16.5 standard limits, not Kaxite production limits. When a customer asks for a gasket in one of these excluded combinations, Kaxite supplies the gasket to the class the standard actually requires and records the class substitution on the dimensional drawing.
On applications where the flange face is narrow or the media is high-pressure gas, a spiral wound gasket or a kammprofile gasket may be the better choice. The double jacketed gasket wins when the flange face is wide (heat exchanger channels, boiler flues, large vessel covers) and the process benefits from a metal-wrapped soft core.
Kaxite Sealing stamps and welds double jacketed gaskets in Ningbo, Zhejiang, on double jacketed gasket production equipment, so jacket stamping, core loading, edge folding and partition-bar welding stay in one facility. Standard sizes ship from stock against the ASME B16.5 table; non-standard sizes and pass partitions are quoted from drawings. Free samples are available for qualified projects with the mill certificate attached. Factory visits and video audits are welcome by appointment; ISO 9001 certificate details are available on request.
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Tell us flange size, ASME B16.5 class, jacket material, core material, gasket thickness and whether a partition bar is required. Free samples and dimensional drawings available for qualified projects.
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No. 432 Zhenhai Middle Road, Luotuo Street, Zhenhai District, Ningbo City, Zhejiang China
