This standard specifies the types, dimensions and technical requirements of non-metallic flat gaskets for steel pipe flanges (European system). HG 20606-1997 Non-metallic flat gaskets for steel pipe flanges (European system) HG20606-1997 Standard download decompression password: www.bzxz.net

Non-metallic flat gaskets for steel pipe flanges
(European system)
HG20606-97
Subject content and scope of application
This standard specifies the type, size and technical requirements of non-metallic flat gaskets for steel pipe flanges (European system). This standard is applicable to non-metallic flat gaskets for steel pipe flanges with a nominal pressure PN of 0.25MPa (2.5bar) to 4.0MPa (40bar) as specified in HG20592. GB539
GB3985
HG20592
《Oil-resistant asbestos rubber sheet》
《Asbestos rubber sheet》
Reference standard
《Types and parameters of steel pipe flanges (European system)》3.0.1 Materials
3 Materials and conditions of use
The materials of non-metallic flat gaskets for steel pipe flanges usually include: 1 Natural rubber and synthetic rubber, such as natural rubber, chloroprene rubber, styrene-butadiene rubber, nitrile rubber, ethylene-propylene rubber, fluororubber, etc.
2 Asbestos rubber sheet (XB350, XB450 of GB3985) and oil-resistant asbestos rubber sheet (NY400 of GB539). Note: When asbestos is not used due to health hazards, the non-asbestos materials listed in 3 and 4 or flexible graphite composite materials can be used. 3 Rubber pressed sheets of synthetic fibers (inorganic, organic). 4 Modified or filled polytetrafluoroethylene sheet.
3.0.2 Service conditions
The service conditions of non-metallic flat gaskets shall comply with the provisions of Table 3.0.2. Table 3.0.2 Service conditions of non-metallic flat gaskets Category
Asbestos rubber
Synthetic fiber rubber
Polytetrafluoroethylene
Natural rubber
Chloroprene rubber
Nitrile rubber
Styrene-butadiene rubber
Ethylene-propylene rubber
Fluororubber
Asbestos rubber sheet
Oil-resistant asbestos rubber sheet
Synthetic fiber
Rubber pressure
Modified or filled polytetrafluoroethylene sheet
Service conditions
P, pressure level (MPa ）
t, Temperature (℃)
50~+90
-40~+100
-30～+110
30～~+100
—40~+130
50~+200
Pt<650MPa.℃
-40~+290
—40～+200
196~+260
Note: There is no corresponding product standard for synthetic fiber rubber pressed sheet and modified and filled polytetrafluoroethylene. When using, the recognized manufacturer's brand should be indicated. 3.0.3 The nominal pressure range of gaskets for flanges with different sealing surfaces is shown in Table 3.0.3. Table 30.3 Nominal pressure range of gaskets for flanges with different sealing surfaces Sealing surface type (code)
Full plane (FF)
Raised face (RF)
Concave and convex face (MFM)
Groove face (TG)
Nominal pressure PN, MPa (bar)
0.25~1.6(2.5~16)
0.254.0(2.5~40)
1.0~4.0(10~40)
1.0~4.0(10~40)
4 Gasket type and size
4.0.1 Gaskets are divided into FF, RF, MFM and TG according to the sealing surface type, which are respectively suitable for full plane, raised face, concave and convex face and groove face flanges, as shown in Figure 4.0.1. , 4.0.2 Gasket size
1·FF gasket size for full-face flanges shall be as specified in Table 4.0.2-1. 2RF gasket size for raised face flanges shall be as specified in Table 4.0.2-2. As required, RF gaskets made of asbestos rubber sheet, oil-resistant asbestos rubber sheet or synthetic fiber rubber pressed sheet may be provided with stainless steel (304) inner edging (RF-E type), and the edging size shall be as shown in Table 4.0.2-2.
3MFM gasket size for concave and convex flanges shall be as specified in Table 4.0.2-3. 4TG gasket size for grooved flanges shall be as specified in Table 4.0.2-4. 5The gasket sizes listed in Tables 4.0.2-1 to 4 are applicable to steel pipe flanges of the two steel pipe outer diameter series A and B listed in HG20592.
6 The gasket inner diameter D1mx in Table 4.0.2-1~3 is applicable to general situations, but it can also be modified according to needs, and the modified inner diameter size should be indicated when ordering. 176
a. FF type (full plane)
b. RF, MFM, TG type (raised surface,
concave and convex surface, trouser groove surface)
C. RF-E type (raised surface, with inner edging)
Type of gasket
Table 4.0.2-1
Dimensions of FF type gasket for full plane flange
PN0. 25MPa(2.5bar)
Bolt hole
Center circle diameter
PN0.6MPa(6bar)
Bolt hole
Bolt hole
Center circle diameter
Continued Table 4.0.2-1
PN1.0MPa(10bar)
Bolt hole
Bolt hole
Center circle diameter
Continued Table 4.0.2-1
PN1.0MPa(10bar)
Bolt hole
Bolt hole
Center circle diameter
tt||Center circle diameter
PN1.6MPa(16bar)
Bolt holewww.bzxz.net
Bolt holeBolt holeCenter circle diameter
Table 4.0.22
Dimensions of RF and RF-E type gaskets for raised face flangesNominal pressure PN,MPa(bar）
Gasket outer diameter Dz
Nominal diameter
Nominal diameter
Table 4.0.2-3Dimensions of MFM type gaskets for raised face flangesGasket inner Diameter
Table 4.0.2-4
Gasket outer diameter
TG type gasket size for grooved flange
Gasket inner diameter
Gasket outer diameter
Gasket thickness
Gasket thickness
Technical requirements
5.0.1 Dimensional deviations of FF and RF gaskets shall be as specified in Table 5.0.1 Table 5.0.1 Dimensional limit deviations of FF and RF gaskets ≤DN300
Inner diameter D
Outer diameter D 2
Full plane bolt center circle diameter K
Center distance of adjacent bolt holes
5.0.2The size limit deviation of MFM and TG gaskets shall be as specified in Table 5.0.2. Table 5.0.2The size limit deviation of MFM and TG gasketsInner diameter DiLimit deviation
≥DN350
Outer diameter D:Limit deviation
5.0.3The thickness limit deviation of the gasket is ±0.20mm, and the thickness difference of the same gasket shall not be greater than 0.20mm. 5.0.4The surface of the gasket shall be flat, without warping and deformation, and no lumps, cracks, bubbles, foreign impurities and other defects that may affect the use are allowed. The edge cutting shall be neat.
5.0.5The gasket shall be made of a whole sheet and splicing is not allowed. For gaskets with an outer diameter greater than 1500mm, if splicing is required, the consent of the purchaser shall be obtained.
Marking example
The raised face flange with a nominal diameter of 100mm and a nominal pressure of 2.5MPa (25bar) uses an XB450 asbestos rubber sheet gasket with an edging of 304 stainless steel. The marking is:
HG20606
Gasket RFE100-2.5
XB450/304
The raised face flange with a nominal diameter of 200mm and a nominal pressure of 1.0MPa (10bar) uses a Garlock G3510 filled polytetrafluoroethylene gasket. The marking is:
HG20606
Gasket RF
Nominal diameter 500mm, nominal pressure 0.6MP a (6bar) full-plane flange with EPDM rubber gasket, marked as: HG20606
Gasket FF
Concave and convex flange with nominal diameter 400mm and nominal pressure 1.6MPa (16bar) uses Garlock IFG5500 inorganic synthetic fiber rubber pressed plate gasket, marked as: HG20606
Gasket MFM
Additional instructions: The proposing unit, chief editor and main drafter of this standard Proposing unit: Equipment Design Technology Center Station IFG5500
Chemical Process Piping Design Technology Center Station of the Ministry of Chemical Industry Chief editor: Equipment Design Technology Center Station of the Ministry of Chemical Industry Main drafter: Ying Daoyan Yu Jun
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.