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This standard is developed in accordance with the rules given in GB/T 1.1-2009.
This standard was proposed by the China Machinery Industry Federation.
This standard is under the jurisdiction of the National Technical Committee on Pipe Fittings of Standardization Administration of China (SAC/TC 237).
Flange connections
1 Scope
This standard specifies the type and parameters, dimension and tolerance, material, type selection, surface treatment, identification, marking, and performance and test requirements of flange connections.
This standard is applicable to flange connections with maximum working pressure of 3.5~42MPa and nominal diameter of DN10~DN127 for hydraulic fluid drive and general purpose.
2 Normative references
The following documents for the application of this document are essential. Any dated reference, just dated edition applies to this document. For undated references, the latest edition (including any amendment) applies to this document.
GB/T 70.1 Hexagon socket head cap screws
GB/T 97.1 Plain washers - Product Grade A
GB/T 131 Geometrical product specifications (GPS) - Indication of surface texture in technical product documentation
GB/T 1804-2000 General tolerances - Tolerances for linear and angular dimensions without individual tolerance indications
GB/T 3098.1 Mechanical properties of fasteners - Bolts, screws and studs
GB/T 3098.2 Mechanical properties of fasteners - Nuts
GB/T 3141 Industrial liquid lubricants - ISO viscosity classification
GB/T 3452.2-2007 Fluid power systems - O-rings - Part 2: Quality acceptance criteria
GB/T 5783 Hexagon head bolts - Full thread
GB/T 6170 Hexagon Nuts, style 1
GB/T 7631.2 Lubricants, industrial oils and related products (Class l) - classification - Part 2: Family H (hydraulic systems)
GB/T 10125 Corrosion tests in artificial atmospheres - Salt spray tests
3 Type and parameters
3.1 Flange connections are classified into two types, i.e., split or integral flange connections and square flange connections, according to the form of flange clamp plate.
a) See Figure 1 for the type of split or integral flange connections and assembly (including bolt).
b) See Figure 2 for square flange connections and assembly.
3.2 Flange connections are classified into light series and heavy series according to the applicable pressure range:
a) The applicable maximum working pressure and the nominal diameter of light series split or integral flange connections are 3.5MPa~35MPa and DN13~DN127 respectively; the applicable maximum working pressure and nominal diameter of heavy series split or integral flange connections are 42MPa and DN13~DN76 respectively.
b) The applicable maximum working pressure and the nominal diameter of light series square flange connections are 25MPa and DN10~DN63 respectively; the applicable maximum working pressure and nominal diameter of heavy series square flange connections are 40MPa and DN10~DN80 respectively.
a) Integral flange clamp plate b) Flange connections and assemblies c) Split flange clamp plate
Keys:
1——Optional shape; 2——O-ring; 3——Flange clamp plate; 4——Flange joint; 5——Bolt;
6——Rigid washer; 7——Port surface of transition block, pump, etc.
Figure 1 Split or integral flange connections and assemblies
a) Flange and flange connection b) Flange and port surface connection c) Square flange clamp plate
Keys:
1——Flange clamp plate; 2——O-ring; 3——Flange joint;
4——Port surface of transition block, pump, etc.; 5——Bolt; 6——Nut.
Figure 2 Square flange connections and assemblies
3.3 The dimension, torque and maximum working pressure of flange connections and assemblies shall meet the following requirements:
a) The dimension, torque and maximum working pressure of light series split or integral flange connections and assemblies shall meet the requirements specified in Table 1; the dimension, torque and maximum working pressure of heavy series split or integral flange connections and assemblies shall meet the requirements specified in Table 2.
b) The dimension, torque and maximum working pressure of light series square flange connections and assemblies shall meet the requirements specified in Table 3; the dimension, torque and maximum working pressure of heavy series square flange connections and assemblies shall meet the requirements specified in Table 4.
3.4 The requirements of pressure and temperature are as follows:
a) The fluid temperature of carbon steel connection at corresponding maximum working pressure specified in Tables 1 and 2 is -40℃~+120℃.
b) The fluid temperature of stainless steel connection at corresponding maximum working pressure specified in Tables 1 and 2 is -60℃~+50℃.
The maximum working pressure of stainless steel connection is changed along with the fluid temperature:
+50℃~+100℃, the maximum working pressure is reduced by 4%;
+100℃~+200℃, the maximum working pressure is reduced by 11%;
+200℃~+250℃, the maximum working pressure is reduced by 20%.
Note: for the connection with synthetic rubber seal ring, its temperature range is depended on the temperature range limit of seal ring.
c) The flange connector specified in this standard cannot be assembled at the temperature below -20℃.
Table 1 Dimension, torque and maximum working pressure of light series split or integral flange connections and assemblies
Nominal diameter of flange DN d1
■(0@-1.5)
mm d2
max
mm Dimension of O-ring
mm Dimension of plain washer
mm Grade 10.9 metric bolt L2
min
mm Maximum working pressure
MPa Minimum burst pressure
MPa
d3 L1a
mm Tightening torque b,c
■(+10%@0)
N·m
13 13.0 13.0 18.64×3.53 8 M8 25 32 16 35 140
19 19.2 19.2 24.99×3.53 10 M10 30 70 18 35 140
25 25.6 25.6 32.92×3.53 10 M10 30 70 18 32 128
32 32.0 32.0 37.69×3.53 10 M10 30 70 18 28 112
38 38.2 38.2 47.22×3.53 12 M12 35 130 23 21 84
51 51.0 51.0 56.74×3.53 12 M12 35 130 23 21 84
64 63.5 63.5 69.44×3.53 12 M12 40 130 23 17.5 70
76 76.2 76.2 85.32×3.53 16 M16 50 295 30 16 64
89 89.0 89.0 98.02×3.53 16 M16 50 295 30 3.5 14
102 101.6 101.6 110.72×3.53 16 M16 50 295 30 3.5 14
127 127.0 127.0 136.12×3.53 16 M16 55 295 30 3.5 14
a The thread length is calculated as that of carbon steel material, and different thread lengths shall be selected if other materials are used.
b The above torque values are calculated according to lubricant bolt and friction coefficient of 0.17; lubrication, coating, surface roughness and other factors influence the tightening torque.
c The flange connections shall be mounted according to the assembling requirements of Annex A.
Table 2 Dimension, torque and maximum working pressure of heavy series split or integral flange connections and assemblies
Nominal diameter of flange DN d1
■(0@-1.5)
mm d2
max
mm Dimension of O-ring
mm Dimension of plain washer
mm Grade 10.9 metric bolt L2
min
mm Maximum working pressure
MPa Minimum burst pressure
MPa
d3 L1a
mm Tightening torque b,c
■(+10%@0)
N·m
13 13.0 13.0 18.64×3.53 8 M8 30 32 16 42 168
19 19.2 19.2 24.99×3.53 10 M10 35 70 18 42 168
25 25.6 25.6 32.92×3.53 12 M12 45 130 23 42 168
32 32.0 32.0 37.69×3.53 12 M12 45 130 23 42 168
38 38.2 38.2 47.22×3.53 16 M16 55 295 27 42 168
51 51.0 51.0 56.74×3.53 20 M20 70 550 35 42 168
64 63.0 63.0 69.44×3.53 24 M24 80 550 50 42 168
76 76.0 76.0 85.32×3.53 30 M30 90 650 60 42 168
a The thread length is calculated as that of carbon steel material, and different thread lengths shall be selected if other materials are used.
b The above torque values are calculated according to lubricant bolt and friction coefficient of 0.17; lubrication, coating, surface roughness and other factors influence the tightening torque.
c The flange connections shall be installed according to the assembling requirements of Annex A.
Foreword II
1 Scope
2 Normative references
3 Type and parameters
4 Dimension and tolerance
5 Material
6 Type selection
7 Surface treatment
8 Identification
9 Marking
10 Performance and test requirements
Annex A (Normative) Connection of split or integral flange - mounting guide
Annex B (Normative) The Dimensions and tolerances of o-ring
Annex C (Informative) Double-hole flange clamp plate