Mechanical Industry Standard of the People's Republic of China Steam Turbine Pipe Accessories Subject Content and Scope of Application Elbows, Tees and Reducers This standard specifies the size series and basic requirements for elbows, tees and reducers. This standard applies to the manufacture and acceptance of elbows, tees and reducers used in the steam turbine industry. 2 Reference standards Sampling method for chemical analysis of steel and allowable deviation of chemical composition of finished products GB223.' Chemical analysis methods for steel and alloys GB228 Metal tensile test method Metal Charpy (U-notch) impact test method Metal Brinell hardness test method GB1804 Tolerances and fits Limit deviations of dimensions without tolerances GB5310 Seamless steel tubes for high-pressure boilers JB2900 Technical conditions for paint for steam turbines Technical conditions for anti-rusting of steam turbines JB2901 JB4377 Provisions for shape and position tolerances of steam turbines without tolerances GB699 Technical conditions for high-quality carbon structural steel 3 Structural types and size series 3. 1. The type and size of the butt-welding 45° elbow are shown in Figure 1 and Table 1. R=1.5D D——Outer diameter Bending radius Mark: Name D×D×8Standard number 8Wall thickness Example: Butt-welding 45° elbow 50×57×5JB/T6296.1-92Approved by the Ministry of Machinery and Electronics Industry on 1992—06-26 16 —Structural length JB/T6296.1-92 —Nominal diameter Implementation of 1993-01-01bzxZ.net P,=4MPa JB/T6296.1-92 P,=6MPa The types and sizes of socket-welded 45° elbows are shown in Figure 2 and Table 2. E9 口A-wrench opening size P,=8MPa d,—Distance P—Die forging curvature size Mark: Name Nominal diameter Type Material Standard number Weight P,=10MPa d: Sleeve welding diameter P,=12MPa h——Sleeve welding pipe depth||t t||Arm radius of sleeve Example: Sleeve welding 45° elbow 50.81 type 12Cr2MolJB/T6296.1-92P,=16MPa Nominal diameter 38.1(No. 1 50:8(2m) .76.2(3\) Material grade 15Cr1Mo 15CriM0 15Cr1Mo JB/T6296.1-92 3.3 The types and dimensions of the butt-welded large radius 90° elbows are shown in Figure 3 and Table 3. Figure 3 D Outer diameter Bending radius Mark: Name D%×D×8 Standard number Structure length Shown Example: Butt-welding type large radius 90° elbow 50×57×5JB/T6296.1-92Dn -nominal diameter JB/T6296.1-92 P,=4MPa P,=6MPa For the type and size of butt-welding type small radius 90° elbow, see Figure 4 and Table 4. Figure D-outer diameter||tt ||R Bending radius Mark: Name DXD×Standard number 8—Wall thickness P,10MPa Structural length Example: Butt-welded small radius 90° elbow 50×57×5JB/T6296.1-92Dn P,=16MPa Nominal diameter JB/T62 96.1-92 P,=4MPa For the types and dimensions of the sleeve-welded 90° elbow, see Figure 5 and Table 5. Concept P,=6MPa □A-wrench opening size H-—elbow end face to center size d, diameter Marking: Name Nominal diameter Type Material brand Standard number de Example: Sleeve-welded 90° elbow 3 8.1(No.1\)Type 125JB/T6296.1-9220 P,=10MPa Socket welding diameter P,=16MPa Arc radius Nominal diameter 12.7(No.) 25.4(1°) 63.5(No.2) 38.1 No. 1 2 63.5(No. 2) JB/T6296.1-92 Material brand 12Cr2Mol 15Cr1Mo 15Cr1Mo 12Cr2Mol 12Cr2Mol 12Cr2Mol 15Cr1Mo 12Cr2Mol 12Cr2Mol 12Cr2Mol 15Cr1Mo 12Cr2Mol 12Cr2Mol 12Cr2Mol 3.6 For the types and sizes of socket-welded equal-diameter tees, see Figure 6 and Table 6d JB/T6296.1-92 Port A—Wrench opening size —Sleeve welding bottom to center size dDiameter Mark: Name Nominal diameter Type Material Brand Standard No. Example: Sleeve welding tee 50.8(- Nominal diameter 12.7(1/2*) 19(3/4m)||tt| |38.1(11/2) 63.5(21/2\) 38.1(11/2\) 19(3/4) 38.1(11/2) 63.5(21/2 Dimension from end face to center of joint Socket welding diameter \)I type 12Cr2MolJB/ T6296.1-92 Material brand 15Cr1Mo 15Cr1Mo 15Cr1Mo 12Cr2Mol 12Cr2Mol 15Cr1Mo 12Cr2Mol 12Cr2Mol 12C r2Mol 12Cr2Mol Arc radius JB/T6296.1-92 For the types and sizes of butt-welded forged tees, see Figure 7 and Tables 7 and 8. 3.7 -Neck diameter -Outer diameter -Neck straight height Mark: Name Nominal diameter Type Material brand d, -Inner diameter Structural length Standard number Example: Butt-welded forged tee 201 type 12Cr1MoVAJB/T6296.1-92 Dimension from joint end face to center Structural width Material brand Working pressure, temperature 12Cr1MoVA|| tt||P=10MPa(100kg) tm540c P=18MPa(184) t=230℃ Material brand Working pressure P≤10MPa 3.8 For the type and size of the reduction section, see Figure 8 and Table 9D, outer diameter of the large end Mark: Name D,× D,×8 Standard number JB/T6296.1-92 Outer diameter of small end Example: Reduction section 50×40×5JB/T6296.1-9224 Structural length Big end millimeter small end 50×40 4Material 4.1Material shall be selected as specified in Table 10. P,=4MPa JB/T6296.192 P,=6MPa P,=8MPa P,=10MPa P,=12MPa P,16MPa Butt-welding 45°elbow Butt-welding 90°elbow Sleeve-welding 45°elbow Sleeve-welding 90°elbow Sleeve-welding tee Butt-welding forged tee Note: The steel types in brackets are not recommended. 4.2 Chemical composition of steel JB/T6296.1-92 oCr19Ni9 15Cr1Mo 15Cr1Mo 12Cr2Mol (1Cr18Ni9Ti) 12Cr1MoVA 4.2.1 The chemical composition of 20 and 25# steels shall comply with the provisions of GB699. 4.2.2 The chemical composition of 15Cr1Mo, 12Cr2Mol, 12Cr1MoVA and 0Cr19Ni9 steels shall be as specified in Table 11. Table 11 15Cr1Mo 12Cr2Mol 12Cr1MoVA OCr19Ni9 4.2.3 The chemical analysis method shall be carried out in accordance with the provisions of GB223 and GB222. 4.3 The mechanical properties of steel shall conform to the provisions of Table 12. Table 12 123~167 Tip: This standard content only shows part of the intercepted content of the complete standard. 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