LamonsLGC US Asset Holdings, LLC

Semi-Metallic gaskets are designed to feature soft, pliable sealing materials - which enhance the tightness of the assembly with lower overall load requirements when compared to full metallic gaskets. They are most popular due to this configuration, and are available in a wide variety of styles and sizes. They can typically be fabricated of any metal which is available in thin strip or sheet, and which can be welded. Therefore, they can be used against virtually any corrosive medium dependent upon the choice of the metal and filler/facing material. Additionally, they can be used over the complete temperature range from cryogenic to approximately 2000ºF. Semi-metallic gaskets can generally be used in pressures ranging from vacuum to those seen in ASME B16.5 standard 2500 pressure class flange ratings. They are resilient and, as a consequence, can compensate somewhat for flange movement that may occur due to temperature gradients, variations of pressure and vibration.

Lamons offers the following filler/facing materials for semi-metallic gaskets:


Filler Material Temperature Range
PTFE -325° F to 500° F
O2i-Oxidation Inhibited Graphite -325° F to 850° F
Oxidation Resistant Grade APX2-FG -325° F to 975° F
HTG (High Temperature Gasket) -325° F to 1500° F
Mica -325° F to 1832° F
Ceramic -325° F to 2000° F


Metallurgies Max Temperature
304SS 1400° F
316SS 1400° F
321SS 1500° F
347SS 1700° F
Titanium 2000° F
Nickle 1400° F
Monel 1500° F
Inconel 600 2000° F
Hastelloy 2000° F


Optimum Gasket Seating Stress
Gasket Type Minimum [PSI] Optimum [PSI] Maximum [PSI]
Spiral Wound
10,000 25,000 40,000
Spiral Wound
5,000 10,000 40,000
3,700 15,000 30,000
LP1 – LP2 – LP3
3,700 15,000 60,000
Double Jacket
(Carbon Steel) STYLE 300
7,600 20,000 35,000
Double Jacket
(Stainless Steel) STYLE 300
9,000 22,000 35,000
CK1 – CK2
3,700 20,000 60,000


Note: Optimum Gasket Stress is based on gasket performance at moderate internal pressure. When working with high internal pressure applications please contact Lamons Engineering Department for clarification. This email address is being protected from spambots. You need JavaScript enabled to view it.

Minimum gasket stress is based on the Y factors of the gasket.

Spiral Wound Gaskets

Lamons Spiral Wound gaskets are available in a variety of styles to suit the particular flange facing being utilized on the flanges.

Kammprofile Gaskets

Lamons Kammprofile gaskets are recognized as a problem solver for heat exchangers, large vessels, and equipment that experience excessive movement due to thermal expansion. The Kammpro provides one of the tightest seals combined with superior load bearing characteristics.

Corrugated Metal Gasket (CMG)

The Lamons CMG family of products are considered the standard in respect to corrugated metal gasket technology; an excellent choice for 150 and 300 class ASME flanges where available bolt loading is minimal.

Metal Jacketed Gaskets

Metallic gaskets can come in different styles like; double jacket, single jacket, or solid metal. Soft compressible filler material can be flexible graphite, PTFE, or non-asbestos compressed sheet type. The design of a metal jacketed gasket also may require different shapes and the styles mentioned above can be made to a variety.

High Temperature Gaskets (HTG)

Lamons high temperature gaskets represent the ultimate solution for industrial bolted joints that are exposed to extreme temperature. The HTG design combines the superior sealing performance of a premium oxidation inhibited grade flexible graphite with an exceptional oxidation barrier in mica/phyllosilicate. The combination of these two sealing materials allows the user to eliminate the effects of oxidation at extreme temperatures.


The Lamons CorruKamm™ resembles a typical kammprofiled sealing element in that it utilizes a heavy substrate capable of extreme load bearing properties. The dramatic feature that this design incorporates is a precisely located corrugated pattern which greatly enhances the ability to deflect and compress under load. This creates a scenario in which the gasket will be more forgiving where perfect alignment and parallelism do not exist.