Semi-Metallic Gaskets
STYLE 911, 911M, 911T and 914
Application / Service
For applications with high temperature variations (thermal cycling), and/or pressure variations, and/or flange rotation problems etc., gaskets with adequate residual stress (stress retention), flexibility and recovery are needed. QUEST spiral-wound gaskets have been designed to meet these demanding requirements.
STYLE 913 and 913M
Spiral Wound Metalflex® Styles
Application / Service
For applications with high temperature variations (thermal cycling), and/or pressure variations, and/or flange rotation problems etc., gaskets with adequate residual stress (stress retention), flexibility and recovery are needed. QUEST spiral-wound gaskets have been designed to meet these demanding requirements.Jacketed Gaskets
Description
A Jacketed Gasket is comprised of a soft pliable core inside a metallic jacket. The following outlines several styles and applications.
Metallic Jacket
Almost any metal or alloy found in sheet form can be used as a jacket; its choice must take into consideration the fluid to be sealed. The metallic jacket is 0.016 in (0.4 mm) to 0.020 in (0.5 mm) thick.
Filler
The standard filler material is Flexible Graphite. Other fillers like ceramic, mica-graphite, PTFE or another metal can be used.
Solid Metal Gaskets
STYLE 900, 940, 941 and 943
Corrugated Metal
Style 900 is a corrugated metal gasket. They are used in low pressure applications where there are limitations of weight and space. The thickness of the sheet should be 0.010 in (0.25 mm) to 0.04 in (1 mm) depending on the metal and number of corrugations. Due to the thickness of the sheet, the force required to seat the gasket is greatly reduced when compared with gasket styles 940 and 941. A minimum of 3 corrugations is necessary to obtain satisfactory sealing. A small flat area on the inside and outside diameters of the gasket is recommended to increase its mechanical strength. The corrugation pitch can vary between 0.045 in (1.1 mm) to 1/4 in (6.4 mm). The total thickness of the gasket is 40% to 50% of the corrugation pitch. The metal used determines the service temperature limit. Maximum service pressure: 500 psi.
Flat Metal
Style 940 is a metallic gasket that has a smooth sealing surface and can be manufactured practically in any shape. Their typical applications are in valves, heat exchangers, hydraulic presses and tongue and groove flanges. The strong points are mechanical and chemical attack resistance and they can be used in elevated temperature and pressure service. The width of the gasket sealing surface should be at least equal to 1.5 times its thickness. These gaskets depending upon their material have high maximum seating stress. The values for the maximum and minimum seating stress are shown in the following table.
Serrated Metal
Style 941 is a flat gasket with concentric grooves. They combine the advantage of the style 940 with a reduced area of contact with the flange to increase the seating stress. It is used when a metallic gasket is required but the available seating force is not enough to seal a style 940. Minimum manufacturing thickness: 3/64 in (1.2 mm).
Jacketed Metal
Style 943. If the service requires the use of style 941 but the flanges need to be protected to avoid being damaged, the 941 gasket can be jacketed.
Corrugated Metal Gasket
STYLE 905
Camprofile
Style 942
Description
Style 942 combines the pressure resistance of flat metal gaskets with the excellent sealability of the Flexible Graphite (Graflex) or Expanded PTFE (24BB), the Camprofile Gaskets. They have a serrated metal core covered on both sides with a thin tape of Flexible Graphite or Expanded PTFE.
The Teadit Camprofile gaskets have the following characteristics:
- Wide range of service.
- Less susceptible to flange imperfections than conventional flat metal gaskets.
The serrated metal core produces a high seating stress with a lower torque. The thin Flexible Graphite or Expanded PTFE core fills up the flange irregularities and prevents the serrated finish from damaging the flanges.