JB/T 1267-2002 Technical Specifications for 50MW～200MW Steam Turbine Generator Rotor Forgings
Some standard content:
ICS77.140.85
Machinery Industry Standard of the People's Republic of China
JB/T1267—2002
Replaces JB/T12671993
50MW～200MW Steam Turbine Generator
Technical Conditions for Rotor Forgings
Specification for rotor forgings for 50MW to 200MW turbine generators2002-12-27 Issued
2003-04-01 Implementation
Issued by the State Economic and Trade Commission of the People's Republic of ChinaForeword
Normative Reference Documents
3 Ordering requirements
4 Technical requirements.
Manufacturing process
Chemical composition,
Mechanical properties
Residual stress
Magnetic properties,
Grain size
Non-destructive testing
Dimensions, tolerances and surface roughness
Inspection rules and test methods
Chemical composition analysis
Mechanical properties inspection,
Residual stress test
Magnetic properties determination
Grain size determination
Hardness inspection
Non-destructive testing.
Retest and reheat treatment
Acceptance and certificate of conformity:
Marking and packaging
Table! Mass fraction of chemical composition
Table 2 Permissible deviation of the mass fraction of chemical composition of finished products exceeding the upper and lower limits Table 3 Mechanical properties.
Table 4 Equivalent diameter and number of single and scattered defects JB/T1267-2002
This standard replaces JB/T1267-1993 (Technical conditions for 50~200MW steam turbine generator rotor forgings). The main changes of this standard compared with JB/T1267-1993 are as follows: - The standard adds a preface:
JB/T1267--2002
- The overall arrangement and structure of the standard are modified according to GB/T1.1-2000 "Guidelines for Standardization Work Part 1: Structure and Writing Rules of Standards":
- In the original standard Table 3 Mechanical properties In the original standard 4.5, the Axv of the III grade forgings is added: except for 25Cr2Ni4MoV, the impact energy value is Aku: In the original standard 4.5, the magnetic properties are changed from B≥2.04T to B≥2.0T: - In the original standard 5.2.4.3: a) Take two tensile specimens (one each) at the bottom of the groove of the two nesting rods, take a room temperature impact specimen and a specimen for measuring the brittle transition temperature at the outer end close to the tensile specimen, and b) The other two nesting rods should be taken in the opposite way, that is, take two tensile specimens (one each) at the outer end, take a room overflow impact specimen and a specimen for measuring the brittle transition temperature at the bottom of the groove. Now it is changed to 1) Take a tensile specimen and two room temperature impact specimens on a busbar. 2) Take a tensile test specimen and two test specimens for measuring the brittle transition temperature on another busbar that is symmetrical in diameter:
In the original standard 5.3.1, the ring core method for measuring residual stress standard JB/T8888 was added. This standard is proposed by the China Machinery Industry Federation. This standard is under the jurisdiction of Deyang Large Castings and Forgings Research Institute. The units that started this standard are Dongfang Electric Co., Ltd. and Harbin Large Electric Motor Research Institute. The main drafters of this standard are Xuan Pinfan and Guo Chenghai. This standard was first issued in 1972, revised for the first time in 1985, and revised for the second time in 1993. III
1 Scope
50MW200MW Steam Turbine Generator
Technical Conditions for Rotor Forgings
JB/T12672002
This standard specifies the technical requirements, inspection rules and test methods, certificates and marks of vacuum-treated alloy steel forgings for rotors of 50MW to 200MW steam turbine generators.
This standard applies to the ordering, manufacturing and inspection of vacuum-treated alloy steel forgings for 50MW200MW steam turbine generator rotors 2 Normative reference documents
The clauses in the following documents become the clauses of this standard through reference in this standard. For all dated referenced documents, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, all parties who reach an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For all undated referenced documents, the latest versions are applicable to this standard. GB/T223.3～78 Chemical analysis methods for steel and alloys GB/T228 Metal tensile test method
GB/T229 Metal Charpy notch impact test method (GB/T229—1994, eqvISO148:1983) GB/T231 Metal Brinell hardness test method
JB/T1581-1996 Ultrasonic flaw detection method for turbine, turbo-generator rotor and main shaft forgings JB/T8468 Magnetic particle inspection method for forged steel parts
JB/T8888 Test method for measuring residual stress of turbine and turbo-generator rotor forgings by ring core method Test method YB/T5148
Method for determination of average grain size of metal
Test methods and definitions for mechanical properties of steel productsASTMA370
ASTMA341
Test method for determining DC magnetic properties of materials by DC impact methodMacro corrosion test method for steel products (including bars, square bars, large square bars and forgings)ASTME381
3 Ordering requirements
3.1 The purchaser shall specify the adopted standards, forging grades, steel grades, corresponding technical requirements and inspection items, as well as other additional instructions in the order contract or technical agreement.
The forging grade and steel number shall be marked on the drawing as follows: Steel number
Forging grade×Number of this standard
3.2 The purchaser shall provide a rough machining drawing indicating the location of the mechanical properties test specimen (provide the finishing dimensions if necessary). 4 Technical requirements
4.1. Manufacturing process
4.1.1 Smelting and pouring
4.1.1.1 Steel for forgings shall be smelted in an alkaline electric furnace. With the consent of the purchaser, other methods of smelting to ensure quality may also be used. 4.1.1.2 Before or during ingot casting, the molten steel shall be vacuum degassed. During the vacuum treatment process, the ultimate pressure of the vacuum system is usually lower than 133Pa. 4.1.2 Forging
4.1.2.1 The upper and lower ends of the ingot shall have sufficient removal to ensure that the forging has no shrinkage cavities and unacceptable segregation. 1
JB/T1267--2002
4.1.2.2 Forging should be done on a forging press with sufficient capacity so that the entire cross section of the forging is fully forged. The axial centerline of the forging and the ingot should roughly coincide. The end of the ingot with better quality should be the turbine end of the forging. 4.1.3 Fillet
At each manufacturing stage, the different step transitions of the forging diameter change should maintain corresponding fillets. 4.1.4 Heat treatment
4.1.4.1 Post-forging heat treatment is normalizing and tempering. 4.1.4.2 Performance heat treatment is quenching and tempering. Normalizing and tempering can also be used with the consent of the belt party. Performance heat treatment should be carried out in a vertical state. The quenching cooling rate on the circumference and the entire length of the forging should be as consistent as possible. 4.1.4.3 After heat treatment and rough machining, the forgings should be subjected to stress relief treatment. The stress relief temperature should be 30℃~55℃ lower than the performance tempering temperature of the forgings.
4.1.5 Machining
The supplier should punch the center hole of the forging before stress relief treatment. 4.1.5.1
4.1.5.2 Take the center hole core rod sample after performance heat treatment. 4.1.5.3
After stress relief treatment, the center hole is finely polished or polished by a method that does not cover defects. The surface roughness R, value is 1.6um. The shipped forgings should meet the size, tolerance and surface roughness requirements specified in the purchaser's order drawings. Chemical composition
The analysis of molten steel should meet the requirements of Table 1. The analysis of finished forgings should meet the requirements of Table 1, but the deviation specified in Table 2 is allowed. The hydrogen content of 200MW rotor forgings is not allowed to exceed 1.5×10-6. Table
Mass fraction of chemical composition
34CrMolA
34CrNiIMo
34CrNi3Mo
25CrNilMoV
25Cr2Ni4MoV
Note: When vacuum carbon deoxidation is used, the silicon content should not be greater than 0.10%. The mass fraction of the chemical composition of the finished product exceeds the maximum range specified by the upper and lower limits of the allowable deviation. Note: When vacuum carbon deoxidation is used, the silicon deviation is 0.02%2
Maximum diameter of rough-machined silver parts mm
571~810
811~1150
4.3 Mechanical properties
4.3.1 The mechanical properties of forgings shall comply with the requirements of Table 3. Item
Recommended steel
Sampling position
Longitudinal, tangential
Longitudinal of center hole
Longitudinal, tangential
Longitudinal of center hole
Longitudinal, tangential
Longitudinal of center hole
Pick, tangential
Longitudinal of center hole
Notch, tangential
Longitudinal of center hole
34CrMo1A
≥440
≥585
25C rNiIMoV
34CrNi1Mo
Table 3 Mechanical properties
≥490
≥640
Forging grade
≥540
≥450
≥640
≥690
34CrNi3Mo
25CrNiiMoV
25Cr2Ni4MoV
The data of grade II forgings in the table are. , 5s, and Axr. >540
≥490
≥665
≥715
≥615
JB/T1267—2002
≥690
≥735
≥640
25Cr2Ni4MoV
For Grade II forgings, except for 25Cr2Ni4MoV, the impact energy data is the value of Aku: When 34CrNi3Mo steel is used for manufacturing, FATTso performance is not required.
4.3.2【, the longitudinal tensile test and the longitudinal transition temperature test of the center hole of Grade II forgings are only carried out when required by the purchaser and are not used as the basis for acceptance.
The fluctuation value of the radial tensile strength or yield strength of the forging shaft is not allowed to exceed 70MPa. 4.3.3
4.4 Residual stress
The residual stress of forgings shall not be greater than 10% of the yield strength value specified in Table 3. 4.5 Magnetic propertiesbzxz.net
Magnetic properties shall meet the following requirements:
H=2.5×10°A/m, then B≥1.44T:
H=5.0×10°A/m, then B≥1.60T:H=10.0×10A/m, then B≥1.72T:
H=15.0×10°A/m, then B≥1.80T:H=20.0×10°A/m, then B1.87T;
H=50.0×10°A/m, then B≥2.0T. Where H is the magnetic field intensity and B is the magnetic induction intensity. 4.6 Grain size
JB/T1267-2002
The inspection results shall be reported to the purchaser, but shall not be used as the basis for acceptance. 4.7 Hardness
Inspect the uniformity of hardness, and the absolute value of hardness is for reference. The hardness deviation shall not exceed 30 Brinell hardness units on the surface of a circular arc, and shall not exceed 40 Brinell hardness units on the same busbar. 4.8 Nondestructive inspection
4.8.1 Magnetic powder or pickling
4.8.1.1 Forgings shall be free of white spots, cracks, folds and other defects. The purchaser reserves the right to use various tests, including pickling or magnetic powder inspection. The purchaser shall carry out pickling or magnetic powder inspection on the R transition zone (one at each end) 200mm outward from both ends of the forging shaft and two bearing parts.
4.8.1.3 The pickling or magnetic particle inspection of the bearing parts and the transition areas at both ends of the shaft body shall meet the following requirements: On an area of 25cm2 (a rectangle with a maximum side length of 15cm), five single defects with a length of 0.5mm1mm are allowed to be displayed, and two single defects with a length greater than 1mm to 1.5mm are allowed to be displayed. No more than 15 single defects are allowed to be displayed in each bearing part. No more than 20 single defects are allowed to be displayed in each transition area.
If the above requirements are exceeded, the supply and demand parties shall negotiate to deal with it. Ultrasonic flaw detection
The outer surface of forgings is subjected to ultrasonic flaw detection, and the results shall meet the following requirements: a) Cracks, white spots and shrinkage holes are not allowed; b) Continuous defect signals and floating defect signals with an equivalent diameter equal to or greater than 2.0 mm are not allowed; c)
Defects with an equivalent diameter less than 2.0 mm are not counted, and scattered defects of 2 mm to 4 mm are allowed, but the distance between two adjacent defects shall not be less than 7 times the diameter of the larger defect;
The equivalent diameter and number of single and scattered defects are not allowed. It is not allowed to exceed the provisions of Table 4: d)
In the area with greater stress (within the range of center hole diameter plus 60mm, and outer groove depth plus 25mm), no single defect with an equivalent diameter greater than 3.0mm (for rotor forgings below 100MW, no equivalent diameter greater than 3.5mm) and no dense defect signal greater than or equal to an equivalent diameter of 2mm are allowed. f)
When using 2MHz~2.5MHz frequency for flaw detection, the attenuation coefficient of the forging material is less than or equal to 4dB/m. Table 4 Equivalent diameter and number of single and scattered defects Equivalent diameter Fantian
4.8.3 Center hole
Allowed number of each part (pieces)
Transmission end
Non-transmission end
4.8.3.1 During the film penetration instrument inspection, the inner surface of the center hole is not allowed to have cracks, shrinkage residual parts, pores, slag inclusions, harmful scratches, defects longer than 5mm and small defects concentrated in a large area. The total number of various defects is not allowed to exceed 30. The specific regulations are as follows: a) The number of defects with a length of 0.5mm1.5mm gathered in an area of 60cm2 shall not exceed 10: b) The number of scattered defects with a length of 1.5mm~3.0mm shall not exceed 10; c) The number of defects with a length of 3mm~5mm shall not exceed five: On the entire surface of the center hole, the number of point defects with a length of 0.5mm~1.5mm shall not exceed 25, and defects with a chain distribution of d
are not allowed.
4.8.3.2 If it is necessary to locally trim or expand the center hole to remove larger inclusions, the purchaser's consent must be obtained in advance. 4.8.3.3 If the purchaser requires magnetic particle inspection of the center hole, it can be carried out by the purchaser. In the event of objections to the magnetic particle inspection, the supply and demand parties shall negotiate to deal with it. 4.9 Dimensions, tolerances and surface roughness
4.9.1 The processing of plated parts shall comply with the dimensions, tolerances and surface roughness requirements specified in the purchaser's order drawings. JB/T1267—2002
4.9.2 The roundness error of the center hole is not allowed to exceed 0.3mm. The surface roughness R of the center hole is 1.6um. The coaxiality error between the center hole and the outer circle shall not exceed 1.0mm. The straightness of the center hole axis shall comply with the following provisions: a) When the delivery length of the forging is less than or equal to 10m, the straightness tolerance value of the center hole axis is within the cylinder with a diameter of 4mm: b) When the delivery length of the forging is greater than 10m, the straightness tolerance value of the center hole axis is within the cylinder with a diameter of 6mm. 5 Inspection rules and test methods
5.1 Chemical composition analysis
5.1.1 Melting analysis
5.1.1.1 The supplier shall take samples for melting analysis when casting each furnace of molten steel and report the analysis results. When multiple furnaces are cast together, the weight analysis results shall also be reported.
5.1.1.2 If the sample is not suitable for smelting analysis, the supplier can take a substitute sample from a suitable position near the surface of the ingot or forging, and inform the buyer of the analysis results and sampling location.
5.1.2 Finished product analysis
The supplier shall conduct finished product analysis for each forging. The sample is taken from the longitudinal sample of the mechanical properties of the forging, and can also be taken from the radial performance sample. The hydrogen content is taken from the radial sample.
5.1.3 Analysis method
Perform in accordance with GB/T223.3~78 and related methods. 5.2 Mechanical property inspection
5.2.1 Perform after performance heat treatment or stress relief treatment. 5.2.2 [, II grade forging tensile test is carried out according to GB/T228 method, and impact test is carried out according to GB/T229 method. The mechanical property inspection of forgings above II grade is carried out according to ASTMA370 method, and the impact test is carried out according to the provisions of V-notch test specimen in ASTMA370. 5.2.3 The notch direction of the radial impact specimen should be as shown in 5.2.4 Sampling location and number of specimens shall comply with the following provisions if there are no special requirements: a) Longitudinal specimens: The supplier and the buyer shall take two tensile specimens and two impact specimens at each end of the forging. Forgings with center holes shall be sampled at 1/2 of the wall thickness: Forgings without center holes shall be sampled at 1/3 of the radius from the surface. Tangential specimens: Tangential specimens shall be cut from test rings cut as close as possible to the 1/3 radius of the shaft surface at both ends of the shaft body. The supplier shall cut the shaft ring at the end of the shaft body with poor quality, and the buyer shall cut the ring at the other end. The cutting of the specimens shall comply with the following requirements 1) For grade II forgings, two tensile specimens and two impact specimens shall be taken at each end of the test ring: 2) For grade IIII and above forgings, four tensile specimens and two impact specimens shall be taken at each end of the test ring, and they shall be cut at the same relative position of the test ring.
c) Radial specimens: Radial material bars should be placed along the radial direction and parallel to the axis. The distance from the two ends of the shaft body shall not be less than 200mm. The hole diameter and hole depth after placing the material should comply with the requirements of the order drawing. The cutting of the specimens should meet the following requirements: 1) Place a tensile specimen and two room temperature impact specimens on one busbar: 2) Place a tensile specimen and two specimens for measuring the brittle transition temperature on another busbar symmetrical in diameter: 3) If the forging groove is narrow or it is not allowed to place radial specimens at other locations, the supplier and the buyer can take two tensile specimens and two room temperature impact specimens on their respective tangential test rings. 4) The impact test specimens for determining the brittle transition temperature shall be carried out at the temperature specified in Table 3, and both specimens shall show at least 50% of the plastic fracture surface:
5) The radial tensile test specimens may be specimens with a diameter of not less than 5mm, and the radial impact test specimens may be 10mm×10mm×55mm (V-notch) specimens,
d) Center hole test specimens: a tensile test specimen shall be taken on the core rod at both ends and the middle of the shaft, and at least four impact test specimens shall be taken on the core rod in the middle of the shaft to determine the value of the brittle transition temperature. 5
JB/T12672002
5.3 Residual stress test
5.3.1 The residual stress shall be determined by the ring cutting method or the ring core method according to JB/T8888. 5.3.2 The supplier and the buyer shall take a 25mm×25mm ring at one end of the forged shaft respectively, and calculate the residual stress by measuring the average deformation of the ring before and after cutting. The calculation formula is: oE6ID
Where:
o, residual stress, unit is MPa:
E--elastic modulus of the material, unit is MPa. 5--algebraic value of diameter increment, unit is mm: D--outer diameter of the ring before cutting, unit is mm: 5.3.3 When the residual stress is unqualified, the forging can be supplemented with tempering. The residual stress inspection results after supplementary tempering shall comply with the provisions of 4.4. 5.4 Magnetic property measurement
The buyer shall measure the magnetic properties of the forgings according to the ASTMA341 method unless otherwise specified by the buyer. Take a magnetic property sample on the tangential test ring of the shaft, and its size shall be determined according to the equipment of each factory. 5.5 Determination of product size
The radial specimen of the shaft body is close to the bottom of the plum and the end surface of the core specimen of the center hole is carried out according to the YB/T5148 method. 5.6 Hardness inspection
After the heat treatment, the supplier shall measure four points (a total of 20 points) at equal distances along the longitudinal direction of the forging at the two shaft necks and three parts of the shaft body, 90 degrees apart on the outer surface: refer to GB/T231 to check the hardness with a hammer hardness tester or other hardness tester. 5.7 Nondestructive inspection
5.7.1 Powder or pickling inspection
5.7.1.1 The purchaser shall pickle the parts specified in the order drawing after semi-finishing, leaving a 2mm margin on one side, and the surface roughness R value is 0.8um.
Pickling is carried out according to the ASTME381 method
If the purchaser requires magnetic particle inspection, it shall be carried out according to the JB/T8468 method. 5.7.1.3
5.7.2 Ultrasonic flaw detection
After rough machining and heat treatment, perform the inspection according to JB/T1581-1996. 5.7.3 Center hole inspection
After the center hole surface roughness R, reaches 1.6μm, use a bore peep tester or magnetic particle inspection, and combine the peep tester to inspect the entire inner hole surface. The magnetic particle inspection is performed according to JB/T8468.
5.8 Retest and reheat treatment
5.8.1 Retest is allowed when the mechanical property test results do not meet the requirements. Retest is not allowed when the test results are unqualified due to cracks or white spots. 5.8.2 When the test results of any sample are unqualified, select two samples at adjacent positions for retest, and the test results of both samples must meet the requirements.
5.8.3 When the retest results of the mechanical property test are still unqualified, the supplier can reheat the forging. Without the consent of the purchaser, the number of re-heat treatments is not allowed to exceed three times. Re-heat treated forgings shall be inspected in accordance with the provisions of 5.2. 5.8.4 When re-heat treating forgings, the remaining center hole core rod shall be put back into the center hole. 6 Acceptance and certificate of conformity
6.1 The supplier shall provide the necessary convenience to the purchaser's inspector so that the purchaser's inspector can carry out his work. The purchaser's inspector shall not cause unnecessary obstruction to the supplier. Unless otherwise specified, all inspections shall be carried out at the supplier. 6.2 Forgings shall be accepted by the supplier's quality inspection department in accordance with this standard, and the purchaser may re-inspect in accordance with this standard. 6.3 The supplier shall provide the purchaser with a certificate of conformity, including the following contents: 62 Ultrasonic flaw detection inspection
After rough machining and performance heat treatment, it is carried out according to JB/T1581-1996 method. 5.7.3 Center hole inspection
After the value of the center hole surface roughness R, reaches 1.6μm, use a bore peep tester or magnetic particle inspection, and combine the peep tester to inspect the entire inner hole surface. The magnetic particle inspection is carried out according to the JB/T8468 method.
5.8 Retest and reheat treatment
5.8.1 Retest is allowed when the mechanical property test results do not meet the requirements. Retest is not allowed when the test results are unqualified due to cracks or white spots. 5.8.2 When the test results of any sample are unqualified, two samples at adjacent positions are selected for retest, and the test results of both samples must meet the requirements.
5.8.3 When the retest results of the mechanical property test are still unqualified, the supplier can reheat treat the forging. Without the consent of the buyer, the number of reheat treatments is not allowed to exceed three times. Reheat treated forgings shall be inspected in accordance with the provisions of 5.2. 5.8.4 When forgings are reheat treated, the remaining center hole core rod shall be put back into the center hole. 6 Acceptance and Certificate of Qualification
6.1 The supplier shall provide the necessary convenience to the buyer's inspector so that the buyer's inspector can carry out his work. The buyer's inspector shall not cause unnecessary obstruction to the supplier. Unless otherwise specified, all inspections shall be carried out at the supplier. 6.2 Forgings shall be accepted by the supplier's quality inspection department in accordance with this standard, and the buyer may re-inspect in accordance with this standard. 6.3 The supplier shall provide the buyer with a certificate of qualification, including the following: 62 Ultrasonic flaw detection inspection
After rough machining and performance heat treatment, it is carried out according to JB/T1581-1996 method. 5.7.3 Center hole inspection
After the value of the center hole surface roughness R, reaches 1.6μm, use a bore peep tester or magnetic particle inspection, and combine the peep tester to inspect the entire inner hole surface. The magnetic particle inspection is carried out according to the JB/T8468 method.
5.8 Retest and reheat treatment
5.8.1 Retest is allowed when the mechanical property test results do not meet the requirements. Retest is not allowed when the test results are unqualified due to cracks or white spots. 5.8.2 When the test results of any sample are unqualified, two samples at adjacent positions are selected for retest, and the test results of both samples must meet the requirements.
5.8.3 When the retest results of the mechanical property test are still unqualified, the supplier can reheat treat the forging. Without the consent of the buyer, the number of reheat treatments is not allowed to exceed three times. Reheat treated forgings shall be inspected in accordance with the provisions of 5.2. 5.8.4 When forgings are reheat treated, the remaining center hole core rod shall be put back into the center hole. 6 Acceptance and Certificate of Qualification
6.1 The supplier shall provide the necessary convenience to the buyer's inspector so that the buyer's inspector can carry out his work. The buyer's inspector shall not cause unnecessary obstruction to the supplier. Unless otherwise specified, all inspections shall be carried out at the supplier. 6.2 Forgings shall be accepted by the supplier's quality inspection department in accordance with this standard, and the buyer may re-inspect in accordance with this standard. 6.3 The supplier shall provide the buyer with a certificate of qualification, including the following: 6
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