SPIRAL WOUND GASKET

Properties and Applications

Spiral wound gaskets are special semi metallic gaskets of great resilience, theretore they are very suitable for applications featuring heavy operating conditions. Spiral wound gaskets are manutactured by spirally winding a Vshaped metal strip and a strip of nonmetallic filler material. The metal strip holds the filler, providing the gasket with mechanical resistance and resilience. Spiral wound gaskets can be reinforced by an outer Stering ring and/or inner retaining ring. The outer centering ring controls the compression and holds the gasket centrally within the bolt circle. The inner retaining ring increases the axial rigidity and resilience of the gasket. Spiral wound gaskets should always be in contact with the flange and should not protrude into the pipe or project from the flange. Spiral wound gaskets can be used for sealing flange joints, manhole and handhold covers, tube covers, boilers, heat exchangers, pressure vessels, pumps, compressors and valves; in industries such as petrochemical, pharmaceutical, shipbuilding, and food processing, in power industries and nuclear power stations. They are ideal for steam, oil, liquids, gases, acids, alkalines, various organic mediums and solvents.

Shape and Construciton

Spiral wound gaskets are produced in several styles and combination of materials to fit the most stringent application. TOUGH+ spiral wound gaskets are usually of circular shape, however TOUGH+ can produce them in other shapes such as: oval, rectangular, with round corners, etc. Our standard production program comprises a range of spiral wound gaskets with inner diameters of 10 to 2200 mm and a nominal thickness of 3.2, 4.5 and 6.5mm. Spiral wound gaskets of nonstandard dimensions and shapes, and larger diameters are available on request.

Gasket Standard Styles

Gaskets without guide and inner ring [Type MS 10|
Gaskets without guide and inner ring [Type MS 10T|*
Gaskets with inner ring (Type MS 12|
Gaskets with guide louter) ring (Type MS 14)
Gaskets with guide and with inner ring [Type MS 16|

Advantages:

Sealing under heaw operating conditions
Strong stress compensation, stable and reliable sealing performance even under frequent pressure fluctuation condition
Solid construction provides stability and seallability even when the sealing surfaces are slightly corroded or bent
Easy installation

Metallic Strip

The standard thickness of the metallic strip is 0,2 mm.

Centering Ring

The centering ring does not come into direct contact with contained fluid. It is normally made of carbon steel and electro plated or painted to avoid corrosion. Other materials are available on request.

Inner Ring

Inner ring is used to avoid excessive compression due to high seating stress in high pressure service and it is also used to reduce turbulence in the flange area. It is normally made of the same material as the gasket metallic strip.

Dimensions

Manufacturing sizes

This limitations are general and can vary according to the special customer

Filler

Filler is normally used for thicknesses from 0,5- 0,6 mm.

Flexible graphite 98%
Flexible graphite 99,85%
PTFE
Ceramic

Thicknesses

The standard manufacturing thicknesses for spiral wound gaskets are:3, 2mm; 4,5mm; 6,5mm (measured across metallic strip not including the filler, which protrudes slightly beyond the metal).

Manufacturing Tolerances

The tolerance of the gasket diameters (d1, d2, d3, d4, s, sl] are stipulated by ASME B 16.20 and EN 1514-2 standards. The gaskets designed for non-standard flanges meet the recommendations by the ASME B 16.20.