Semi-metallic gaskets are designed to fill the gap between metallic gaskets and soft ones. They also have a series of combined features of each. Spiral Wound gaskets and Metal Jacketed gaskets are the most preliminary type of semi-metallic gaskets. The latter ones are composed of a metal cover over a filler material. The sealing function of Metal Jacketed seals is efficient for a wide range of temperatures and pressures up to 6,000 psi, as well as various applications such as refineries, aerospace industries, and chemical processing plants. Additionally, due to the availability of Metal Jacketed gaskets to be fabricated in various shapes, they offer economical sealing devices for narrow flanges and heat exchanger jointing.

Single Jacketed Gasket	Single Jacketed Overlap Gasket	Double Jacketed Gasket	Corrugated Jacketed Gasket

Applications:
Narrow flanges, Valve bonnet gaskets, Exhaust gases, Heat exchangers, and a wide range of chemical environments.
There are also 4 different types of metal jacketed gaskets which are expressed below thoroughly.

Double Metal Jacketed: These gaskets are soft filler material embedded in a metal jacket and insert. The main application of these gaskets is environments with elevated temperature and pressure.

Double metal jacketed Corrugated: The construction procedure of these gaskets is designed to diminish the contact area which also has enabled these gaskets to be applicable for uneven flanges and lower bolt loads.

Single Jacketed: These gaskets are mainly designed for applications in which the flange width does not allow using of double jacketed gaskets. Single Jacketed gaskets are constructed out of a soft filler completely inserted in a single jacket.

Single Jacketed Overlap Gasket: This precisely engineered PALMFOX Single Jacketed Overlap Gasket consists of PTFE or Graphite filler inserted into a steel Single Jacketed Overlap. The soft filler material and steel core bestow this sealing system a high level of tightness and strength respectively. Single Jacketed Overlap Gasket is primarily applied in heat exchangers and small recess gaps.

Typical specifications of different types of PALMFOX metal jacketed gaskets:

1. PALMFOX double jacketed type 100

General properties:
Additional gasket stability and blow-out resistivity due to inserted metallic jacket. Chemical stability to different ranges of media.

2. PALMFOX type 108

General properties:
A sealing system with wide seating face for medium pressure applications.
Premium tightness for low bolt loads.
Economical selection of sealing systems at lower pressures.

 3. PALMFOX Maxigraph

Metal Jacketed Partition Connection

One-Piece Construction (Endless)
These are manufactured using a single sheet of material.
This can therefore restrict the size of the gasket available as it is dependent on the sheet size of material available, generally between 1400 mm and 1800 mm in diameter. The pass partition bars are also in this one-piece construction intersecting with the outside ring. Should leakage occur, the flow path will follow along the length of the pass bar to the outer diameter of the ring where sealing will become reliant and be maintained by the secondary seal.

Welded Construction
This type of construction does not have any restrictions on gasket size. It is also generally more cost-effective as the process is quicker and the material yields higher. The pass partition bars are securely welded into place with soft and small spot welds in two places at each end of the bar. Any leak path is retained by the primary seal at the inner diameter of the gasket, therefore, providing a technically superior gasket seal.