HG 20627-1997 Non-metallic flat gaskets for steel pipe flanges (American system)
Basic Information
Standard ID:
HG 20627-1997
Standard Name: Non-metallic flat gaskets for steel pipe flanges (American system)
Chinese Name:
钢制管法兰用非金属平垫片(美洲体系)
Standard category:Chemical industry standards (HG)
state:Abolished
Date of Release1998-02-01
Date of Implementation:2000-01-01
Date of Expiration:2009-07-01
Some standard content:
Non-metallic flat gaskets for steel pipe flanges (American system) HG 20627-97 1 Subject content and scope of application This standard specifies the types, dimensions and technical requirements of non-metallic flat gaskets for steel pipe flanges (American system). This standard applies to non-metallic flat gaskets for steel pipe flanges with a nominal pressure PN of 2.0MPa (Class 150) to -5.0MPa (Class 300) as specified in HG20515. 419 GB 3585 HG20615 Cited standards Oil-resistant asbestos rubber sheet Asbestos rubber sheet Types of steel pipe flanges, reference (American 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, butadiene rubber, nitrile rubber, ethylene rubber, fluororubber, etc.
(2) Asbestos rubber sheet (XB350, XB450 of GB3985) and oil-resistant asbestos rubber electrode (NY400 of GB539). Note: When asbestos is prohibited from use due to health hazards, etc., the asbestos materials or flexible composite gaskets listed in (3) and (4) shall be used. () Synthetic red fiber rubber pressed electrode (inorganic, molded) (4) Modified or filled polytetrafluoroethylene sheet. 3.0.2 Conditions of use
The conditions for use of non-metallic flat gaskets shall comply with the provisions of Table 3.0.2. Table 3.0. 2. Use conditions of non-gold screen flat gaskets: Asbestos rubber, synthetic fiber rubber, polyurethane, natural rubber, tt rubber, butyl rubber, styrene butadiene rubber, ethylene propylene rubber, bottle rubber, asbestos rubber plate, styrene rubber plate, synthetic fiber rubber, modified or filled polypropylene plate. Use conditions: P, Strength grade (MPa), Temperature (°C), 50~+ 90, -40~-100, --- 30~--- 110 30--101
- 40-:—13(
P.650MPa. C
10--1290
-40--+200
196·-.269
Process: Synthetic fiber rubber pressed, modified, filled with polytetrafluoroethylene. Corresponding product specifications, when using the recognized manufacturer's brand, please indicate the recognized manufacturer's brand. 3.0.3 The suitable range of these gaskets for flanges with different sealing surfaces is shown in Table 3.0.3. Table 3.0.3 The applicable range of gaskets for flanges with different sealing surfaces. Sealing surface type (code)
Full plane (FF)
Relief (RF)
Point surface (MFM)
Horizontal surface (TC)
Heat MPaC
2. GCiass 150)
3.0(Clasa 155)-~5.0(Class 00)5.0(Chass 30)
5.0rclass 300)
Nominal reverse diameter, m
15~630
15~-150t:
15~690
15~690
Gasket type and size
4.0.1 Gasket sealing surface type is divided into FF type, RF type, MFM type and TG type: applicable to F full T surface, raised surface, concave and convex surface and grooved surface respectively. As shown in Figure 4.0.1. 4.02 Gasket size
1 The size of FF type gasket for full plane difference shall be specified in Table 1.0.2-1. 2. The dimensions of the gasket for the flange with a concave or convex surface shall be as specified in Table 4.0.2-2-3. According to the requirements, the RF type gasket made of rubber sheet, oil-resistant rubber cavity sheet or synthetic fiber can be provided with stainless steel (304) inner edging (RF...E type), and its edging dimensions shall be as shown in Table 4.0.2-2-3. The dimensions of the MFM type gasket for the flange with a concave or convex surface shall be as specified in Table 4.0.2-4, and the dimensions of the TG type gasket for the flange with a 4-layer surface shall be as specified in Table 4.0.2-5. 422
b.RF type, MFM type, TG type
C.RF-E type
Figure 4.0.1 Gasket type
Nominal diameter
Table 4..2-1bzxZ.net
Table 4.0.2-2
Nominal diameter
Dimensions of FF type gasket for full-face flange
PN2.0MPa(CEaks150)
Screw hole
Bolt hole
Center circle diameter of screw hole
Dimensions of RF and RF-E type gasket for DN600mm raised face flange Gasket
Nominal service PN.MPa(Class)
(Class 150)
(Class 300)
Gasket outer diameter D:
Table 4.0.23DN>600mm raised face large diameter flange RF and RF-E type gasket dimensions European diameter
Nominal diameter
Table 4.0.24
Nominal PN,MPa(Class)
(Class 1s)
(Class 300)
Gasket outer diameter D:
Mem type gasket dimensions for recessed face flange
Nominal diameter
Table 4.0.2 -- 5
Dimensions of TG type gaskets for sample groove surface method
5The gasket sizes listed in Table 4.0.2--1 to 5 are applicable to steel pipe flanges engraved with HG20615 426
Technical requirements
5.0.1The dimensional deviations of FF type and RF wall gaskets shall be as specified in Table 5.0.1. Table 5.0.1 Size limit deviation of FF and RF gaskets SDN0G
Inner diameter D
Outer diameter Dz
Full plane bolt center circle diameter K
Center distance of adjacent screw holes
±1- 5
5.0.2 Size limit deviation of MFM and TG gaskets shall be as specified in Table 5.0.2 Table 5.0.2 Size limit deviation of MFM and TG gaskets Inner diameter D, Limit deviation
(mrn)
Outer diameter Dz Limit deviation
5.0.3 The thickness limit deviation of the gasket is ±0.20nrn, and the thickness difference of the same gasket should not be greater than 0.20mm. The surface of the gasket should be flat, without warping and deformation, and no lumps, cracks, bubbles, foreign impurities and pits that may affect the use are allowed. The edge cutting should be neat.
5.0.5 The gasket should be made of a whole sheet of plate, and splicing is not allowed. Gaskets with an outer diameter greater than 1500mm: If splicing is required, the purchaser’s consent must be obtained.
Marking example
The raised face flange with a nominal diameter of 100mm and a nominal pressure of 2.0MFPa (Class 150) uses an XB450 right cotton rubber plate with an edge covered with 304 stainless steel, which is marked as:
HG20627
1002 5
XB450/304
The raised face flange with a nominal diameter of 200mm and a nominal pressure of 5.0)MPa (Class 300) uses a polytetrafluoroethylene gasket filled with Garlock's G3510, which is marked as: HG 20627
The full-plane cover with a nominal diameter of 500mm and a nominal pressure of 2.0MPa (Class 150) uses an EPDM rubber gasket, which is marked as:
HG 20627
500—2.0
Large diameter raised face flange with nominal diameter of 800mm and nominal pressure of 2.0MPa (Class 150) Garlock IFG5500 inorganic synthetic fiber rubber pressed gasket, marked as: HG 20627
800—2.0
JFG 5500
Nominal diameter of 500mm, nominal pressure of 5.0MPa (Clnss300) concave and convex flanges use XB450 stone rubber sheet gaskets. The mark is:
HG 20627
Additional note: This standard proposes the unit, editor and main drafter XB450
Proposing unit: Chemical Industry Department Chemical Process Piping Design Technology Center Station Chemical Industry Department Equipment Design Technology Center Station
Editor: Chemical Industry Department Equipment Design Technology Center Station Main drafter: Ying Daoyan Yu Jun
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