Toothed gasket

Tooth shape composite gasket

Tooth shape metal composite gasket belongs to a kind of metal composite gaskets, commonly used special precision lathe or milling machine first in the two aspects of metallic flat gasket processed into concentric waveform 90 degrees Angle of sawtooth groove, is due to contact with other sealing surface of multiple concentric line contact, so have labyrinth seal effect, according to the different medium and working condition, can choose flexible graphite, PTFE, non asbestos board or some other soft metal, paste the two aspects of the gasket, the use of soft cover sealing and the strength of the metal and resilient advantages, in order to achieve better sealing effect, in most cases it is recommended that graphite as sealing layer, when the medium for clean environment or react to graphite we suggest to choose the newly launched the excellence performance of bulk four fluorine stickup layer upon layer, generally don't need a lot of pressure, sealing effect could be achieved.
Tooth shape also can not take cover sealing gasket composite layer used directly, can also achieve good sealing effect, but in high-pressure situations to cause damage to the surface of the flange.So generally requires sealing surface roughness Ra1.6 um above.
Special application conditions such as high temperature, strong corrosion and other special metal tooth material combination shim, we also can produce the following some material may be required to:
Stainless steel 304 l, 321316 TI, 304, dual phase steel (2205318-03), MONEL MONEL (400), indium secco nickel INCONEL (600625), INCOLOY (800825), hartz alloy HASTELLO (B2, C276), titanium (T2), and other special stainless steel or alloy materials.

Tooth shape metal composite gasket performance characteristics:

1. Low pre-tightening force, even in a high pressure environment also has a good sealing effect, especially suitable for high temperature and high pressure, working conditions of alternating occasion is a traditional metal winding gasket and metal cladding gasket is the ideal substitute.
2. The metal composite gasket to seal the surface of tooth profile is not damage, easy to remove.
3. The metal part can be repeated use for tooth form larger gaskets or special materials gaskets such as heat exchanger gasket has the vital significance.

Tooth shape metal composite gasket application:

Toothed composite gasket is mainly used in petroleum, chemical industry, metallurgy, electric power, shipbuilding, machinery and other industries, the high pressure and high temperature pressure vessels, heat exchanger, condenser, and the joint of pipe flange seal.

Toothed composite gasket structure and symbol and use the flange type:

The basic pattern
Code name Applicable flange sealing surface Thickness (mm)
The seal body Paste layer (single)
basic ZD-1900A Grooved surface, concave and convex surface, plane and the surface of the groove Three, four, five 0.5 to 1.0
With outer ring (fixed) ZD-1901C Flat or convex Three, four, five 0.5 to 1.0
With outer ring (activities) ZD-1902C Flat or convex Three, four, five 0.5 to 1.0
Bring earrings ZD-1903C Flat or convex Three, four, five 0.5 to 1.0

Toothed composite gasket various non-metallic materials main technical parameters:

material Identification code Temperature ℃ The maximum working pressure Applicable medium Compression ratio % Resilient rate % The stress relaxation rate %
Expanded graphite F.G.
- 220-550 250 BAR Corrosive medium
P 17 18 or less
teflon PTFE - 100-200 100 BAR Corrosive medium 18-30 15 or more 13 or less
Expansion of ptfe EPTFE
- 100-260 200 BAR Corrosive medium 25-35 25 or higher 13 or less
No asbestos material NA
- 100-350 100 BAR General air tightness 18-30 P 19 28 or less
Cloud mother MICA
- 150-800 100 BAR High temperature, 18-30 P 19
Ceramic fiber CER
- 200-1090 100 BAR Ultra high temperature 18 to 40 P 19

In the table below for tooth profile combination gasket commonly used metal skeleton material selection:

The name of the material
Abbreviations tag Hardness (HB) The limit temperature (° C)
Carbon steel (Carbon steel) CRS 120 - 40 ~ + 540
304 stainless steel 304 130 ~ 180 - 195 ~ + 760
304 l stainless steel 304L 130 ~ 180 - 195 ~ + 760
316 l stainless steel 316L 130 ~ 180 - 100 ~ + 760
317 l stainless steel 317L - 100 ~ + 760
321 stainless steel 321 130 ~ 190 - 195 ~ + 760
347 stainless steel 321 - 185 ~ + 760
20CB-3(ALLOY 20) A-20
- 185 ~ + 1090
- 185 ~ + 1090
- 185 ~ + 1090
INCOLOY-800 IN 800 - 100 ~ + 870
INCOLOY-825 IN 825 - 100 ~ + 870
INCONEL-600 INC 600 150 - 100 ~ + 1090
INCONEL-625 INC 625 - 100 ~ + 1090
INCONEL-X750 INX - 100 ~ + 1090
MONEL-400 MON 150
- 130 ~ + 820
NICKEL - 200 (ni) NI
- 195 ~ + 760
TITANIUM (ti) TI 215
- 195 ~ + 1090

The size of the tooth profile composite gasket limit deviation:

Tooth shape seal diameter D1 in the body
Tooth shape seal diameter D2 in the body D3 outer diameter The thickness of the T
+ 1.5
+ 1.5
+ 0.25

Toothed composite gaskets main performance parameters:

Coefficient of gasket
Gasket using pressure ≤25MPa
Gasket using temperature - 196 ℃ to 650 ℃ (oxidizing medium is not higher than 450 ℃)
Gasket than the minimum preload pressure y=50MPa

Does the client choose according to different working conditions of using different skeleton material and adhesive layer, general with stickup layer performance as the main reference, such as the requirement of high temperature resistant with graphite, corrosion resistant with four fluorine.

Tooth shape metal composite gasket technology standards:

1. The tooth shape metal composite gasket foreign standards are: ASME B 16.5, BS1560, ASME B 16.47, BS EN1092, DIN2697, JIS and NF.
2. The national standard JB/T 88-1994 line tooth shape with the metal in the flange gasket The mechanical standard
HB 6474-1990 | tooth gasket Aerospace standard
HG20611-2009 steel pipe flange with tooth profile composite gasket chemical system in Europe
HG20632-2009 steel pipe flange gasket with tooth profile combination Chemical system of America
More standards or requirements, please inquire

Does the actual application condition is complex, the above parameters are for reference only do not make any guarantee is requested.

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