Specification for rotor and shaft forgings for 25MW to 200MW steam turbines
1 Scope
This standard specifies the technical requirements, testing rules, test methods, quality certificate and marking of vacuum-treated alloy steel forgings for rotors and shafts for 25MW to 200MW steam turbines.
It is applicable to the order, manufacturing and testing of vacuum-treated alloy steel forgings for rotors and shafts for steam turbines with steam temperature not exceeding 565℃.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections), or revisions, of any of these publications do not apply to this standard. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition applies.
GB/T 223.3~78 Methods for chemical analysis of iron, steel and alloy
GB/T 228 Metallic materials - Tensile testing
GB/T 229 Metallic materials - Charpy notch impact test (GB/T 229-1994, eqv ISO 148:1983)
GB/T 231 Metallic materials - Brinell hardness test
GB/T 2039 Metallic materials - Creep and stress-rupture test in tension (GB/T 2039-1997, eqv ISO/DIS 204:1997)
GB/T 10561 Steel - Determination of content of non-metallic inclusion - Micrographic method using standard diagrams (GB/T 10561-1989, eqv ISO 4967:1979)
JB/T 1581 Ultrasonic testing method for rotor and shaft forgings of steam turbine and turbine generator
JB/T 8468 Magnetic particle testing for steel forgings
JB/T 8888 Test method for measuring residual stresses by the ring-core method in rotor forgings for turbine and generator
JB/T 9021 Thermal stability test method of stream turbine main shafts and rotor forgings
YB/T 5148 Metal - Methods for estimating the average grain size
ASTM A370 Standard test methods and definitions for mechanical testing of steel products
ASTM E292 Standard test methods for conducting time-for-rupture notch tension tests of materials
3 Order requirements
3 1 The purchaser shall indicate the adopted standard, steel grade, corresponding technical requirements, testing items as well as those testing items beyond this standard in the order contract.
3.2 The purchaser shall provide the order drawing of forgings with marked sampling position for mechanical performance test and finish machining dimension of blade groove depth.
3.3 Items to be inspected on site as required by the purchaser shall be indicated in the contract.
4 Technical requirements
4.1 Manufacturing process
4.1.1 Smelting and pouring
Contents
Foreword i
1 Scope
2 Normative references
3 Order requirements
4 Technical requirements
4.1 Manufacturing process
4.2 Chemical component
4.3 Mechanical performance
4.4 Hardness
4.5 Non-destructive testing (NDT)
4.6 Heat stability test
4.7 Metallographic testing
4.8 Residual stress
4.9 Dimension and surface roughness
5 Testing rules and test methods
5.1 Chemical component analysis
5.2 Mechanical performance testing
5.3 Hardness testing
5.4 Non-destructive testing
5.5 Metallographic testing
5.6 Measurement of residual stress
5.7 Heat stability test
5.8 Retest
5.9 Re-heat treatment
6 Acceptance and quality certificate
7 Marking and packaging
Table 1 Mass fraction of chemical component
Table 2 Permissible deviation of mass fraction of finished product chemical component
Table 3 Mechanical performance
Table 4 High temperature endurance strength of 30Cr1Mo1V steel forgings
Table 5 Quantity of permissible defects
