There are many application standards for pressure pipeline components in China's pipeline standard system, but they are not complete. Taking pipeline flange standards as an example, commonly used standards include GB national standards, JB mechanical industry standards, SH petrochemical industry standards, and Hg chemical industry standards. Each of these standards has its own temperature and pressure gauge, sealing surface size, and nozzle size. Their interchangeability is poor, and some cannot even be used together. In order to better apply these standards, this article introduces the commonly used Chinese pressure pipeline application standard system.
Application Standard System for Petrochemical Industry
The pipe diameter series standard (sh3405) basically belongs to the "large outer diameter series"
Sh3405 is equivalent to the ISO 4200 standard, so when DN1100mm is used, it can be used in conjunction with the ANSI b36.l/36.19 standard.
SH3405 diameter range and wall thickness classification:
Number Steel Pipe Category Nominal Diameter Range Wall Thickness Classification
1) Austenitic stainless steel seamless steel pipe 10-400 (sch5s, sch10s, sch20s, sch40s, sch80s)
(2) Seamless carbon steel and alloy steel pipes with sizes ranging from 10 to 600, including sch20, sch30, sch40, sch60, sch80, sch100, sch120, sch140, sch160, and XXS
(3) Austenitic stainless steel welded steel pipe 80-1000 (2.0-12mm)
(4) Carbon steel and alloy steel welded steel pipe 150-2000 (4.0-18mm)
Flange standard (sh3406): Belongs to "American style flange"
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Pn15.0 (cl900)[UNK]pn25.0 (cl1500) [UNK]pn42.0 (cl2500)
Nominal diameter: DN15～dn1500mm
Flange sealing surface: There are 5 types of sealing surfaces for DN600, including convex surface, concave convex surface, full plane, mortise and tenon groove surface, and ring groove surface
When DN650, one convex platform
Flange type: There are 5 types for DN600, including flat welding, butt welding, socket welding, threaded connection, and loose fitting
650 types of butt welding according to the Chinese pipeline standard system DN1
Sh3406 is equivalent to ANSI B16.5 and API 605 standards. Sh3406 has good interchangeability with ANSI b16.5/api605 in terms of structural dimensions and sealing surface types. It can be used with ANSI, API, MSS, and other standard piping components. However, due to the use of Chinese material standards instead of American material standards (ASTM) in sh3406, there are slight deviations in the temperature and pressure gauges between the two. Therefore, when considering the interchangeability of the two, attention should be paid to and the corresponding temperature and pressure allowable values should be checked.
General standards in the application standard system of the petrochemical industry
SH3401 pipe flange gasket made of asbestos rubber sheet
SH3402 PTFE coated gasket for pipe flange
SH3403 metal ring gasket for pipe flange
SH3404 pipe flange fasteners
SH3405 steel pipe size series for petrochemical enterprises
SH3406 petrochemical steel pipe flange
SH3407 pipe flange wrapped gasket
SH3408 steel butt welded seamless pipe fittings
SH3409 steel plate welded pipe fittings
SH3410 forged steel socket welded pipe fittings
The petrochemical application standard system belongs to a relatively complete application standard system. Because it is equivalent to ANSI standards, it represents advanced and developmental directions. And because its flange (sh3406) can be matched with API standard valves. In recent years, the application has proven that this application standard system is a scientific, advanced, and operable standard system.
Application standard system in the chemical industry
Pipe diameter series standard (hg20553) series a: belongs to the "large outer diameter series"
B series: belongs to the "small outer diameter series"
The flange standards include European and American flanges
European flange (hg20592~hg20605)
Pressure rating: PN 0.25, 0.6, 1.0, 1.6, 2.5, 4.0, 6.3, 10.0, 16.0, 25.0, etc
Nominal diameter: dn10~dn2000mm
Flange types: plate type flat welding, neck type flat welding, neck type butt welding, integral type, socket welding, threaded, butt welding ring loose sleeve, flat welding ring loose sleeve, flange cover, lining flange, etc
Sealing surface types: convex surface, concave convex surface, tenon groove surface, ring connection surface, full flat surface, etc.
Can be used in conjunction with JB valve
American flange standard (hg20615-hg20626)
Nominal pressure: pn2.0, pn5.0, pn11.0, pn15.0, pn26.0, and pn42.0
Nominal diameter: DN15-1500
Flange types: 6 types, including neck flat welding, neck butt welding, integral flange, socket welding, threaded, loose fitting, etc,
There are 5 types of sealing surfaces: convex surface, concave convex surface, mortise and tenon groove surface, ring connection surface, and full flat surface
The pressure pipeline application standard system in the chemical industry is also a relatively complete standard system, which has undergone several years of production practice and has mature usage experience. Because it has two series: "large outer diameter series" and "small outer diameter series", "European flange" and "American flange", it has a wide range of applications. It can be used in combination with foreign standards such as ANSI, DIN, ISO, as well as domestic standards such as GB, SH, JB, etc.
General standards in the application standard system of the chemical industry
Specification for Selection of Hg 20537.1 Austenitic Stainless Steel Welded Steel Pipe
HG 20553 Seamless and Welded Steel Pipe Size Selection Series for Chemical Pipeline
Hg/T 21634 forged steel socket welded pipe fittings
Hg/T 21635 carbon steel and low-alloy steel butt welded pipe fittings
Hg/T 21631 steel seam butt welded pipe fittings
Hg/T 21632 forged steel socket welding, threaded and butt welded pipe frame
Hg/T 21637 Chemical Pipeline Filter
Hg/T 21577 quick special connector
Hg 20592-20605 steel pipe flange (European series)
Hg 20615-20626 steel pipe flange (American system)
Hg 20606-20612 steel pipe flange gasket (European series)
Hg 20627-20633 steel pipe flange gasket (American system)
Hg 20613 steel pipe flange fastener (European series)
Hg 20634 steel pipe flange fastener (American system)
Application standard system in the mechanical industry
The pipe size belongs to the "small outer diameter series"
Flange standard: European flange
Pressure levels: 10 pressure levels including PN 0.25, 0.6, 1.0, 1.6, 2.5, 4.0, 6.3, 10.0, 16.0, 20.0, etc
Nominal diameter: DN15~DN1600mm
Flange types: integral, plate flat welding, butt welding, flat welding ring plate loose sleeve, butt welding ring plate loose sleeve, flip plate loose sleeve, flange cover
Sealing surface types: flat, convex, concave convex, mortise and tenon surface, and ring connection surface.
JB does not have corresponding pipe diameter series standards and pipe fitting standards, and the system is very incomplete, requiring support from the GB system;
The JB flange standard lists different grades of materials in the same temperature and pressure gauge, thus losing its scientific validity;
The JB valve standard provides a limited selection series of models (reflected in product assembly), which not only limits its scope of use, but also loses flexibility. From the application of numerous production units, the performance of JB valves is not satisfactory; JB valves cannot be used in conjunction with ANSI, making it inconvenient to integrate with the world;
The general standards in the application standard system of the mechanical industry include:
JB/T74 Technical Conditions for Pipeline Flanges
JB/T75 pipeline flange type
JB/t79.1-79.4 integral cast steel pipe flange
JB/T81 flat welded steel pipe flange
JB/t82.1-82.4 butt welded steel pipe flange
JB/t83 0.25, 0.6, 1.0, 1.6, 2.5MPa flat welding ring loose sleeve steel pipe flange
JB/T84 4.0, 6.3, 10.0MPa Concave convex surface welded ring plate loose sleeve steel pipe flange
JB/T85 0.25, 0.6MPa flange loose sleeve steel pipe flange
JB/t86.1-86.2 steel pipe flange cover,
JB/4700-4703 Pressure Vessel Flanges
JB/T87-90 pipeline flange gasket
Pressure vessel gaskets Jb4704~4706
National Application Standard System
The pipeline size series standard GB17395 belongs to the "large outer diameter series"
Flange standard: (GB/T 9112-2000) includes European and American flanges
The nozzle is divided into series I and series II
The I series is the "large outer diameter series" to match the SH standard;
Series II is a "small outer diameter series" that complies with JB standards.
European flange: divided into I series and II series,
Nominal pressure: PN 0.25, 0.6, 1.0, 1.6, 2.5, 4.0, 6.3, 10.0, 16.0mpa, Level 9
Nominal diameter: dn10～2000mm
Flange type: integral, with neck thread, butt welding, with neck flat welding, plate flat welding, flat welding ring plate loose sleeve, butt welding ring plate loose sleeve, flanged ring plate loose sleeve, flange cover
Sealing surface types: flat, convex, concave convex, and mortise and tenon surfaces.
American flange: I series (large outer diameter)
Nominal pressure: PN 2.0, 5.0, 11.0, 15.0, 26.0, 42.0 MPa (Level 6)
Nominal diameter: dn10-600mm
Flange type: integral, with neck thread, butt welding, with neck flat welding, with neck socket welding, butt welding with ring neck loose sleeve and flange cover
Sealing surface types: flat, convex, concave convex, mortise and tenon surface, and ring connection surface.
Basically, it can include the "European" standards of JB and Hg, creating conditions for the replacement of these two standards;
The temperature and pressure ratings of "European style flanges" and "American style flanges" are determined by comparing the performance of Chinese materials with European and American materials, and selecting the pressure and temperature parameters of the corresponding materials specified in ISO 7005-1.
The national standard system for pressure pipelines is also a relatively complete standard system. The pipe fitting standards are divided into two series, A and B. The A series is the "large outer diameter series" to comply with SH standards; The B series is a "small outer diameter series" that complies with JB standards.
General Standard of China National Application Standard System
GB 12459 Steel butt welded seamless fittings
GB/T 13401 Steel Plate Welded Pipe Parts
GB/T 14626 Forged steel threaded fittings
GB/T 14382 Three way Filters for Pipelines
GB/T 14383 Forged steel socket welded fittings
GB/T 9112-9124 Steel Pipe Flanges
GB 4622.1-3 Spiral wound gaskets for pipe flanges
GB 9126.1-4 Asbestos rubber gaskets for pipe flanges
GB 9128.1-2 Metal ring gaskets for pipe flanges
GB/T 13404 PTFE coated gaskets for pipeline flanges
GB/T 15601 Metal Composite Gaskets for Pipe Flanges
National standard 30 hexagonal bolt
GB 52 hex nut
GB 56 Hexagonal Coarse Nut
GB 901 equal length double head screw B-grade
GB 6170 Type I hex nut, Class A and Class B
GB 6171 Type I hex nut, fine thread, Class A and B
GB 6175 Type II Hexagon Nut Class A and B
GB 6176 disc-shaped hexagonal nut, fine tooth, Class A and Class B
Standard system for pressure pipeline application
There are many standard systems available for pressure pipeline applications, some of which cannot be used together. Although some can be used together, there are still some issues that need to be noted. One device or multiple devices built simultaneously should adopt the same application standard system as much as possible to avoid errors caused by coordination between different standard systems. In projects, it is common to encounter the simultaneous use of two or more application standard systems on a single device, or the need for support from other system standards due to incomplete application standards of one standard system. This requires material engineers not only to understand the relevant standard system, but also to understand the standard coordination between various systems. Pay attention to checking the temperature and pressure values of each standard.
The standards for various valves also vary with changes in pipeline system standards