Specification for steel pipe flanges in petrochemical engineering
1 Scope
This standard specifies the nominal diameter, nominal pressure, types, dimensions, tolerances, material, pressure-temperature ratings, manufacture, inspection and marking requirements of steel pipe flanges.
This standard is applicable to the manufacture and acceptance of steel pipe flanges in petrochemical engineering.
2 Normative references
The following referenced documents are indispensable for the application of this standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 713 Steel plates for boilers and pressure vessels
GB/T 3274 Hot-rolled plates, sheets and strips of carbon structural steels and high strength low alloy structural steels
GB/T 3531 Steel plates for low temperature pressure vessels
GB/T 24511 Stainless steel and heat resisting steel plate, sheet and strip for pressure equipments
GB/T 12716 Pipe threads with the thread angle of 60 degrees where pressure-tight joints are made on threads
NB/T 47013.4 Nondestructive testing of pressure equipments - Part 4: Magnetic particle testing
NB/T 47013.5 Nondestructive testing of pressure equipments - Part 5: Penetrant testing
NB/T 47008 Carbon and alloy steel forgings for pressure equipment
NB/T 47009 Alloy steel forgings for low temperature pressure equipment
NB/T 47010 Stainless and heat-resisting steel forgings for pressure equipment
SH/T 3401 Nonmetallic flat gaskets for steel pipe flanges in petrochemical industry
SH/T 3402 Polytetrafluoroethylene envelope gaskets for steel pipe flanges in petrochemical industry
SH/T 3403 Metallic ring joint gaskets for steel pipe flanges in petrochemical industry
SH/T 3404 Fasteners for steel pipe flanges in petrochemical industry
SH/T 3405 Series of steel pipe size in petrochemical industry
SH/T 3407 Spiral wound gaskets for steel pipe flanges in petrochemical industry
ASME B16.5 Pipe flanges and flanged fittings
ASME B16.47 Large diameter steel flanges
ASTM A105/A105M Standard specification for carbon steel forgings for piping applications
3 General requirements
3.1 Nominal diameter and outer diameter of steel pipe
Nominal diameter and outer diameter of the steel pipe applicable to the flanges shall be determined based on those specified in Table 3.1.
Table 3.1 Nominal diameter and outer diameter of the steel pipe
3.2 Nominal pressure
The nominal pressure of flanges is divided into eight classes: Class 75, Class 150, Class 300, Class 400, Class 600, Class 900, Class 1500 and Class 2500. The range of nominal diameters corresponding to each nominal pressure class shall meet those specified in Table 3.2.
Table 3.2 Nominal diameter ranges for corresponding nominal pressure classes
3.3 Flange types
3.3.1 Flanges are classified into weld neck flanges, slip-on flanges, socket welding flanges, lap joint flanges, threaded flanges, and blind flanges, the codes of which shall meet those specified in Table 3.3.1.
Table 3.3.1 Types and codes of flanges
Type of flange Code Type of flange Code
Weld neck flange WN Lap joint flange LJ
Slip-on flange SO Threaded flange PT
Socket welding flange SW Blind flange BL
3.3.2 Flange sealing faces are classified into raised face, flat face, female and male face, tongue and groove face, and ring joint face, the codes of which shall meet those specified in Table 3.3.2.
Table 3.3.2 Types and codes of sealing faces
Type of sealing face Code
Raised face RF
Flat face FF
Female and male face MF (with LF for female face, and LM for male face)
Tongue and groove face TG (with GF for groove face and TF for tongue face)
Ring joint face RJ
3.3.3 The applicable range for types of flanges with a nominal diameter less than or equal to DN 600 shall meet those specified in Table 3.3.3.
Table 3.3.3 Applicable range for types of flanges with a nominal diameter less than or equal to DN 600
Foreword i 1 Scope 2 Normative references 3 General requirements 3.1 Nominal diameter and outer diameter of steel pipe 3.2 Nominal pressure 3.3 Flange types 3.4 Flange facing finish 4 Flange types, dimensions and tolerances 4.1 Types and dimensions of flanges with a nominal diameter less than or equal to DN 4.2 Lap joint flange and lap joint stub ends 4.3 Sealing face size of flanges with male and female faces (MF face flanges) and tongue and groove faces (TG face flanges) 4.4 Types and dimensions of Series A flanges with a nominal diameter greater than DN 4.5 Types and dimensions of Series B flanges with a nominal diameter greater than DN 4.6 Tolerances 4.7 Flange welding ends configuration dimensions 5 Materials 5.1 General requirements 5.2 Technical requirements 6 Manufacture and heat treatment 6.1 Manufacture 6.2 Heat treatment 7 Inspection and tests 7.1 Inspection 7.2 Tests 8 Product quality certificate 9 Marking, protection and packaging 9.1 Marking 9.2 Protection and packaging Annex A (Normative) Pressure-temperature ratings Annex B (Informative) Length of fasteners Explanation of wording in this standard
a)平焊法兰 b)对焊法兰 c)承插焊法兰 d)螺纹法兰 e)法兰盖 环槽剖面详图 f)环槽面法兰和法兰盖 图4.1.1 Class150法兰结构型式 表4.1.1 Class150法兰尺寸及质量 公称直径DN 法兰外径O mm 管子插入孔B0 mm 法兰内径Ba mm 法兰颈部尺寸mm 密封面外径R mm 法兰厚度Q mm 最小螺纹长度T mm 法兰高度Y mm 承插深度D mm 螺栓、螺柱 环号及环槽面尺寸 法兰近似质量kg 中心圆直径C mm 孔径h mm 螺纹 孔数 个 金属环垫号 环槽面尺寸mm 两法兰间近似尺寸S mm 对焊法兰 平焊法兰 承插焊法兰 法兰盖 X H 对焊型 其余 P E、W F r K
a 法兰内径应根据相连钢管的壁厚确定,表中所列法兰内径B是根据相连钢管壁厚为SCH40时计算的内径。 4.1.2 Class300法兰结构型式见图4.1.2,法兰尺寸及质量应符合表4.1.2的规定。
a)平焊法兰 b)对焊法兰 c)承插焊法兰 d)螺纹法兰 e)法兰盖 环槽剖面详图 f)环槽面法兰和法兰盖 图4.1.2 Class300法兰结构型式 表4.1.2 Class300法兰尺寸及质量 公称直径DN 法兰外径O mm 管子插入孔B0 mm 法兰内径Ba mm 法兰颈部尺寸mm 密封面外径R mm 法兰厚度Q mm 最小螺纹长度T mm 最小螺纹沉孔直径V mm 法兰高度Y mm 承插深度D mm 螺栓、螺柱 环号及环槽面尺寸 法兰近似质量kg 中心圆直径C mm 孔径h mm 螺纹 孔数 个 金属环垫号 环槽面尺寸mm 两法兰间近似尺寸S mm 对焊法兰 平焊法兰 承插焊法兰 法兰盖 X H 对焊型 其余 P E、W F r K
a 法兰内径应根据相连钢管的壁厚确定,表中所列法兰内径B是根据相连钢管壁厚为SCH40时计算的内径。 4.1.3 Class400法兰结构型式见图4.1.3,法兰尺寸及质量应符合表4.1.3的规定。