JB/T 1265-2002 Technical requirements for rotor and main shaft forgings of 25MW to 200MW steam turbines
Some standard content:
ICS77.140.85
Machinery Industry Standard of the People's Republic of China
JB/T1265—2002
Replaces JB/T1265--1993
Specification for rotor and shaft forgings for25MW to200MW steamturbines
2002-12-27 Issued
2003-04-01 Implementation
Issued by the State Economic and Trade Commission of the People's Republic of China Foreword
Normative references
Ordering requirements
Technical requirements
Manufacturing process
Chemical composition.
Mechanical properties.
Non-destructive inspection
Thermal stability test
Metallographic inspection.
Residual stress.
Dimensions and surface roughness
Inspection rules and test methods
Chemical composition analysis,
Mechanical properties inspection
Hardness inspection.
Non-destructive testing
Metallographic testing.
Residual stress determination
Thermal stability test
Reheat treatment
Acceptance and certificate of conformity
7 Marking and packaging
Table Mass fraction of chemical composition
Table 2 Permissible deviation of mass fraction of chemical composition of finished productTable 3 Mechanical properties.
Table 4 High temperature endurance strength of 30Cr1Mo1V steel forgingsTable 5 Permissible number of defects
JB/T1265-2002
JB/T1265—2002
This standard replaces JB/T1265-1993 "Technical Conditions for Rotor Body and Main Shaft Forgings for 25~200MW Steam Turbines". Compared with JB/T1265-1993, the main changes of this standard are as follows: the chemical composition of 30Cr2Ni4MoV steel is changed, and the P and S contents are reduced (4.2 of the 1993 edition, 4.2 of this edition); - the mechanical properties of 30Cr2Ni4MoV steel forgings are changed according to 10325UC-UD, and the plasticity and toughness indicators are improved (4.3 of the 1993 edition, 4.3 of this edition);
For 30Cr1Mo1V steel forgings, the provision of "using the No. 6 specimen of ASTME292" is added for high temperature endurance strength test (5.2.2 of the 1993 edition, 5.2.3 of this edition);
- the provision of "according to JB/T8888" is added for measuring residual stress by ring core resistance strain method (see 5.6.3); the contents related to rotor forgings without center hole are supplemented. This standard is proposed by China Machinery Industry Federation. This standard is under the jurisdiction of Deyang Large Castings and Forgings Research Institute. The drafting unit of this standard is Shanghai Steam Turbine Co., Ltd. The main drafters of this standard are Wang Siyu and Shen Hongwei. This standard was first issued in 1972, revised for the first time in 1985, and revised for the second time in 1993. 1 Scope
JB/T1265—2002Www.bzxZ.net
Technical conditions for rotor bodies and main shaft forgings of 25MW~200MW steam turbines This standard specifies the technical requirements, inspection rules, test methods, certificates and marks of vacuum-treated alloy steel forgings for rotor bodies and main shafts of 25MW200MW steam turbines. This standard applies to the ordering, manufacturing and inspection of vacuum-treated alloy steel forgings for rotor bodies and main shafts of steam turbines with steam temperatures not exceeding 565℃.
2 Normative references
The clauses in the following documents become the clauses of this standard through reference in this standard. For any dated referenced document, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, parties to an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For any undated referenced document, the latest version applies to this standard. GB/T223.3~78 Chemical analysis methods for steel and alloys Metal tensile test method
GB/T228
GB/T229
GB/T 231
Metal Charpy notch impact test method (GB/T229--1994, eqvISO148:1983)Metal Brinell hardness test method
Metal tensile end deformation and endurance test method (GB/T2039--1997, eqvISO/DIS204:1997)GB/T2039
GB/T10561
JB/T1581
JB/T8468
JB/T8888
JB/T9021
YB/T5148
Method for microscopic evaluation of non-metallic inclusions in steel (GB/T10561-1 989, eqvISO4967:1979) Ultrasonic flaw detection method for turbine, turbine generator rotor and main shaft forgings Magnetic particle inspection method for forged steel parts
Test method for measuring residual stress of turbine and turbine generator rotor forgings by ring core method Test method for thermal stability of turbine main shaft and rotor forgings Method for determining average grain size of metal
ASTMA370
Mechanical property test method and definition of spiral products Metal tensile endurance test method
ASTME292
3 Ordering requirements
3.1 The purchaser shall specify the adopted standard, steel grade, corresponding technical requirements, inspection items and inspection items other than the requirements of this standard in the order contract.
3.2 The purchaser shall provide the order drawing of the satin parts indicating the sampling position for mechanical property test and the deep finishing size of the blade root groove. 3.3 The items that the purchaser requires to participate in on-site inspection shall be stated in the contract. 4 Technical requirements
4.1 Manufacturing process
4.1.1 Refining and pouring
4.1.1.1 Steel for forgings shall be smelted in electric furnaces, and ladle refining and electric remelting processes may be used. Other methods of smelting that ensure quality may also be used with the consent of the purchaser.
4.1.1.2 Molten steel shall be vacuum treated before or during pouring to remove harmful gases, especially hydrogen. During the vacuum treatment process, the capacity of the vacuum system must be large enough to reduce the initial increased pressure to a low value within 2 minutes after pouring, which should usually be lower than 133Pa. -
JB/T1265—2002
4.1.1.330Cr1Mo1V steel shall be silicon deoxidized: 30Cr2Ni4MoV steel shall be vacuum carbon deoxidized. Other deoxidation methods may be used after consultation between the two parties.
4.1.2 Forging
Sufficient removal shall be made on the upper and lower parts of the steel ingot to ensure that the finished forgings are free of shrinkage, looseness, severe segregation and other harmful defects. 4.1.2.1 Forging
4.1.2.2 The forging method adopted must make the entire forging have a uniform structure as much as possible. The forging press shall have sufficient tonnage to forge the entire cross section of the forging, and the axis of the forging shall be kept as close to the center line of the steel as possible. Unless otherwise specified in the order contract, the better end of the steel ingot shall be the end close to the generator
4.1.3 Heat treatment
4.1.3.1 The heat treatment after forging shall be normalizing and tempering. 4.1.3.2 After the first rough machining, the forgings shall be subjected to performance heat treatment. Forgings made of steel for high and medium pressure rotor bodies shall be subjected to normalizing and tempering. Normalizing cooling shall be blast cooling. Other cooling methods may be adopted upon agreement between the two parties. Forgings made of steel for low pressure rotor bodies shall be subjected to rate tempering and tempering. The rotor body forgings shall be in a vertical state during heat treatment. The normalizing or rate tempering temperature shall be higher than the phase change temperature, but lower than the normalizing temperature of the post-forging heat treatment. al
b) The tempering temperature should be as high as possible while ensuring that the mechanical properties meet the requirements. The tempering temperature of high and medium pressure rotor steel should not be lower than 660℃, and the tempering temperature of low pressure rotor steel should not be lower than 580℃ (30Cr2Ni4MoV steel should not be lower than 570℃) 4.1.3.3 After performance heat treatment and subsequent rough machining (after the center hole of the perforated rotor is punched), the forging should be stress-removed within the range of 15℃~50℃ below the final tempering temperature, but should not be lower than 550℃ (for 30Cr2Ni4MoV steel, it should not be lower than 540℃). After obtaining the consent of the purchaser, the stress removal temperature may be higher than the upper limit specified in this standard. At this time, the center hole specimen of the perforated rotor should be returned to its original corresponding position. After stress removal treatment, a supplementary tensile test must be carried out. 4.1.4 Machining
4.1.4.1 Before the performance heat treatment, all surfaces of the forgings shall be subjected to the first rough machining. Without the consent of the purchaser, no groove cutting or impeller step machining between the integral impellers shall be carried out before the performance heat treatment and formal ultrasonic flaw detection. 4.1.4.2 After the performance heat treatment, the forgings shall be subjected to the second rough machining.4.1.4.3 For forgings with holes, the center hole shall be drilled according to the size and tolerance requirements specified in the order drawing of the purchaser, and the center hole core rod shall be inserted. In order to remove the unacceptable central defects detected by ultrasonic detection, the center hole may be enlarged within the limit range indicated in the order drawing or agreed by the purchaser, and its surface roughness R value shall not be greater than 1.6 m4.1.4.4 For forgings with holes, the center hole shall be finely bored after stress relief treatment, and polished or polished by a method that will not cover defects. 4.1.5 Welding
During the manufacturing and packaging process, the rotor body and the main shaft forgings shall not be welded. 4.2 Chemical composition
4.2.1 The supplier shall conduct smelting analysis on each batch of molten steel, and the mass fraction of its chemical composition shall comply with the provisions of Table 1. Table 1 Mass fraction of chemical composition
3aCaMol
crtMolv
34CtNi3Mo
28GMONiV
X0606V
0.30~0.38
0.25~0.30
0.40~0.70
0.70~1.00
0.20~0.40
When vacuum carbon deoxidation is adopted,
0.17~0.37
0.20 ~0.35
0.17~0.37
0.70~1.20
≤0010
Silicon content should not be greater than 0.10%.
0.70~1.10
L.10~0.40
1.50~2.00
2.75~3.25
0.50~0.75
3.25~3.75
1.00~1.30
0.89~1.00
0.25~0.35
0.07~0.15
JB/T12652002
The supplier shall conduct finished product analysis for each forging. The mass fraction of the chemical composition shall comply with the provisions of Table 1, but deviations specified in Table 2 are allowed.
Allowable deviation
Mechanical properties
Upper limit of Mn composition
Allowable deviation of mass fraction of chemical composition of finished product%
The mechanical properties of forgings shall comply with the provisions of Table 3. +0.005
Table 3 Mechanical properties
S,(6,)
Sampling position
Longitudinal direction of shaft end
Radial direction of body
Longitudinal direction of center hole
Longitudinal direction of shaft end
Radial direction of body
Longitudinal direction of center hole
Longitudinal direction of shaft end
Radial direction of body
Longitudinal direction of center hole
Longitudinal direction of shaft end
Longitudinal direction of shaft end
Longitudinal direction of body
Longitudinal direction of center hole
Longitudinal direction of shaft end
Body radial
Center hole longitudinal
Axle carbon longitudinal
Body radial
Center hole longitudinal
Recommended steel
≥(345)
≥(345)
≥(14)
≥(40)
34CrMo1
≥490
≥490
≥640
≥640
≥600
≥(15)
≥ (13)
》(45)
≥(40)
28CrMoNiV
590~690
590690
≥550
≥720
≥690
≤116
30Cr1Mo1V
Ni component upper limit
degree level
690~790
690~790
≥660
》790
≥760
≥18 (14)
≥18 (12)
≥18(12)
≥56(40)
≥56(35)
≥53(35)
≥95 (50)
≥95 (45)
≥61 (35)
30Cr2Ni4MoV
34CrNi3Mo
Note 1: For forgings with center hole, only the longitudinal performance of the shaft end and the center hole are measured, and the tangential performance is taken for those without center hole. Note 2: The data in brackets for strength levels 690 and 735 are the properties of 34CrNI3Mo steel Mo
±0.01! +0.02
735~835
735~835
≥685
≥855
≥(11)
≥(10)
30Cr2Ni4MoV
34CrNi3Mo
760860
760~860
≥860
≥830
30CY2Ni4MoV
Note 3: 34CrNi3Mo steel forgings can provide body radial and center hole longitudinal FATT data, which are not subject to assessment. When the purchaser has requirements, 30Cr1Mo1V steel forgings should use smooth-notched composite specimens for high temperature endurance strength test, and the results 4.3.2
should meet the requirements listed in Table 4.
Humidity ℃
High temperature endurance strength stress of 30Cr1Mo1V steel forgings MPa
Test requirements
New time more than 100h
Elongation ≥15%
Fracture shall not be on the V-notch
JB/T1265—2002
4.4 Hardness
Forgings shall be inspected for uniformity of hardness after heat treatment, and the absolute value of hardness is for reference. The hardness difference between points on the same circumference shall not exceed 30HBS, and the hardness difference on the same busbar shall not exceed 40HBS. 4.5 Nondestructive inspection
4.5.1 General requirements
Forgings shall not have cracks, white spots, shrinkage cavities, folds, excessive segregation, and inclusions and looseness exceeding the allowable level. 4.5.2 Magnetic Particle Inspection
After the outer cylindrical surface of the forging is finely processed, the purchaser shall conduct magnetic particle inspection on the bearing surface, the outer end faces of the two shaft bodies and the transition zone (the entire outer cylindrical surface may be inspected if necessary). The supplier shall ensure that the inspection results meet the following requirements: a) No defects greater than 1.5mm in length are allowed on the bearing part of the outer cylindrical surface of the rotor body, and no defects greater than 3mm in length are allowed in other parts.
During the final inspection of the rotor body, except for the bearing part, if defects greater than 1.5mm are found in other parts, local b)
grinding and polishing are allowed. The polishing depth should not exceed 1.6mm and should have a smooth transition with the surrounding surface. c) When the distance between two defects on the same busbar is less than five times the length of the larger defect, it shall be treated as a continuous defect. 4.5.3 Ultrasonic testing
4.5.3.1 Single scattered defect signals with an equivalent diameter of less than 2mm are not counted, but the noise height should be less than 50% of the amplitude of the equivalent diameter of 2mm. Note: Single scattered defects refer to defects where the distance between two adjacent defects is greater than 10 times the equivalent diameter of the larger defect. 4.5.3.2 The axial, radial and circumferential positions of all defects with an equivalent diameter of 2mm to 5mm should be recorded and reported to the purchaser. No defects with an equivalent diameter greater than 5mm are allowed. The equivalent diameter and number of single scattered defects in different parts of the forging should not exceed those specified in Table 5.
Table 5 Allowable number of defects
Equivalent range
> $4 ~±5
Allowable number of defects in different parts
Transmission end
Non-transmission end
Note: Both ends of the medium-pressure rotor body and the low-pressure rotor body are transmission ends, so the allowable number of defects at both ends is in accordance with the provisions of the transmission end, and the total number of allowable defects
4.5.3.3 Within 30mm from the center hole surface of the shaft body (within 75mm from the axis of the rotor without center hole) and within 25mm of the outer circle planting depth, there should be no dense signal defects with an equivalent diameter of 1.6mm. Single scattered defects with an equivalent diameter of less than 3mm are allowed. If dense defects are detected in other areas, the size of the dense defect area and its axial, radial and circumferential positions should be recorded and reported to the purchaser for review. 4.5.3.4 When the bottom wave attenuation loss caused by defects reaches 3dB, it should be recorded and reported to the purchaser. 4.5.3.5 No wandering signals or strip defect signals are allowed. 4.5.3.6 The supplier shall provide the buyer with the material attenuation data measured at the two ends and three locations in the middle of the rotor body with the maximum diameter at 2MHz~2.5MHz and 4MHz~5MHz.
4.5.3.7 When the ultrasonic flaw detection results of the forgings exceed the above provisions, the supplier and the buyer shall conduct re-inspection and discussion, but whether the forgings can be judged as qualified shall be determined by the buyer.
4.5.4 Center hole inspection
After the center hole of the forging with holes is finely polished or ground to a surface roughness of R≤1.6um, the center hole inspection shall be carried out. The acceptance criteria are as follows:
The axial and circumferential positions of defects equal to or greater than 1.5mm in length shall be recorded and reported to the buyer: a)
JB/T1265—2002
b) Within the range of 60cm\, three visible defects with a length greater than 1.5mm or nine visible defects with a length less than 1.5mm are not allowed:||tt| |c) The total length of all defects on the same generatrix on the inner hole surface should not be greater than 50mm: d) No tear-like bifurcation defects are allowed: e) When the distance between two defects on the same generatrix is less than 5 times the length of the larger defect, it shall be treated as a continuous defect: f) Visible defects with a length greater than 3mm and dense areas composed of non-metallic inclusions are not allowed; g) For defects that do not meet the requirements of 4.5.4, local grinding and polishing of the defects are allowed with the consent of the purchaser, but the depth of grinding and polishing should not exceed 1.6mm, and there should be a smooth transition with the surrounding surface. 4.6 Thermal stability test
The thermal stability test can be done by the purchaser, but the supplier shall be responsible for the test results. 4.7 Metallographic inspection
4.7.1 Average grain size of forgings: 30Cr1Mo1V steel should not be coarser than grade 2.0, and other steel types should not be coarser than grade 3.0. 4.7.2 The four types of inclusions A, B, C, and D of forgings should not exceed grade 3.0. 4.8 Residual stress
The residual stress of forgings should be measured, and its value should not be greater than 8% of the lower limit of radial compressive strength in Table 3. If the residual stress exceeds the above provisions, the forgings should still be supplemented with stress relief tempering in accordance with the provisions of 4.1.3.3, and the residual stress and hardness value should be re-measured. 4.9 Size and surface roughness | |tt||4.9.1 The processed forgings shall meet the requirements of size, tolerance and surface roughness specified in the order drawing. 4.9.2 If the order drawing does not specify, the straightness tolerance of the center hole axis is $3mm: the roundness tolerance of the center hole is 0.3mm, and the coaxiality tolerance of the center hole and the outer ring of the forging is 1.0mm.
5 Inspection rules and test methods
5.1 Chemical composition analysis
5.1.1 Chemical composition analysis shall be carried out in accordance with the methods specified in GB/T223.3~78 or other methods that can ensure the quality of analysis. 5.1.2 Each furnace (each package) of molten steel can be sampled during pouring to determine the chemical composition of the molten steel: when multiple furnaces are poured together, the weighted average analysis results shall also be reported. When smelting analysis is not possible, finished product analysis is allowed to replace smelting analysis. When sampling is taken from forgings, the analysis results shall meet the requirements of finished product analysis.
5.1.3 The finished product analysis specimen can be taken from the extended part of the forging at 1/3 of the surface, or from the radial performance acceptance test. 5.2 Mechanical performance inspection
5.2.1 Tensile performance inspection
Perform according to the methods specified in GB/T228 and ASTMA370. 5.2.2 Impact test
Perform according to the methods specified in GB/T229
5.2.3 High temperature endurance strength test
Perform according to GB/T2039, using No. 6 specimen of ASTME292. The test can be carried out at the purchaser, but the supplier shall ensure that the test results meet the requirements of Table 4.
5.2.4 Sampling for mechanical performance inspection
5.2.4.1 The specimens used for mechanical performance inspection shall be cut after performance heat treatment and before stress relief treatment. 5.2.4.2 Longitudinal specimens: Take one tensile specimen and three impact specimens at each end of the forging. The sampling position is 1/3 away from the surface. 5.2.4.3 Radial specimens: For rotors with a weight less than or equal to 6t after rough machining, take one tensile specimen and three impact specimens on the impeller body near the motor end; for rotors weighing more than 6t, take one tensile specimen and three impact specimens on the impeller body at both ends of the rotor body at 180° intervals (a total of four tensile specimens and 12 impact specimens), and take a group of FATTso specimens as required. FATTs can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. JB/T12652002
5.2.4.4 Center hole specimens: For forgings with a center hole greater than Φ90mm, take one tensile specimen, three impact specimens and a group of FATTso specimens from the center hole bar in the middle of the shaft body, and take one tensile specimen and three impact specimens from the shaft body near the motor end. FATTso can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. 5.3 Hardness test
One point shall be measured every 90° on the outer surface of the two journals and the shaft of each forging (a total of 12 points). The hardness test shall be carried out in accordance with the method specified in GB/T231.
5.4 Nondestructive testing
5.4.1 The magnetic particle test of the outer surface shall be carried out in accordance with JB/T8468, and the ultrasonic test of the outer surface shall be carried out in accordance with JB/T1581. 5.4.2 The ultrasonic test shall be carried out at least twice, the first test shall be carried out before quenching and tempering (before the center hole is punched for forgings with holes), and the second test shall be carried out after quenching and tempering (before the center hole is punched for forgings with holes). The results of both tests shall be provided to the buyer. If the buyer deems it necessary, the center hole ultrasonic test may be carried out. The center hole ultrasonic test shall be carried out in accordance with the method agreed upon by both parties. The supplier shall ensure that the center hole ultrasonic test results meet the requirements of the relevant provisions of this standard. 5.4.3 The center hole test shall be observed by a magic bore instrument, and if necessary, the center hole magnetic particle test shall be combined with a barrier instrument for observation. 5.5 Metallographic inspection
5.5.1 Grain size inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and conduct according to the provisions of YB/T5148. 5.5.2 Inclusion inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and evaluate according to the rating diagram I in Appendix A of GB10561. 5.6 Determination of residual stress
5.6.1 The residual stress is determined by the ring cutting method or the ring core resistance strain method. 5.6.2 The ring cutting method is to cut a 25mmx25mm ring at one end of the shaft, and calculate the residual stress by measuring the average deformation of the ring before and after cutting. The calculation formula is:
0=E6/D
Where:
\-residual stress, unit is MPa:
E--elastic modulus of the material, unit is MPa. 8 Algebraic value of diameter increment, in mm
D---outer diameter of the ring before cutting, in mm: 5.6.3 When the residual stress is determined by the ring core resistance strain method, it shall be carried out in accordance with the provisions of JB/T8888. 5.7 Thermal stability test
The thermal stability test shall be carried out in accordance with the provisions of JB/T9021. 5.8 Retest
5.8.1 If a test result in the tensile test is unqualified, two specimens can be taken from the forging adjacent to the original specimen for retest, and the retest results of the two specimens shall meet the specified requirements. 5.8.2 In the impact test, if the average value of a group of three impact specimens is not lower than the specified requirements, and one of the values is not lower than 70% of the specified requirements, no retest is required: When the above requirements are not met, another group of three impact specimens shall be taken from the adjacent parts of the same product for retest, and the average value of the six specimens in the two groups before and after shall not be lower than the specified requirements, and there shall be no more than two single values lower than the specified value, and only one single value can be lower than 70% of the specified value.
5.8.3 If the mechanical property test fails due to white spots and cracks, retesting is not allowed. 5.9 Re-tempering
5.9.1 If the re-test result of any mechanical property of the forging is still unqualified, when the strength of the specimen is high but the plasticity, toughness or FATT does not meet the requirements, it is necessary to re-temper. For forgings with holes, the center hole specimen should be re-inserted into the hole and re-tempered together with the forging. After tempering, it should be inspected according to the provisions of 5.2. The sampling position of the center hole specimen of the forging with holes after re-tempering should be agreed upon with the purchaser. 5.9.2 If the mechanical property test results show that the forging cannot be re-tempered, the further heat treatment and processing of the forging must be agreed upon by the supply and demand parties.6um, the center hole inspection is carried out, and the acceptance criteria are as follows:
The axial and circumferential positions of defects equal to or greater than 1.5mm should be recorded and reported to the purchaser: a)
JB/T1265—2002
b) Within the range of 60cm\, three visible defects with a length greater than 1.5mm or nine visible defects with a length less than 1.5mm are not allowed:
c) The total length of all defects on the same generatrix on the inner hole surface should not be greater than 50mm: d) No tear-like bifurcation defects are allowed: e) When the distance between two defects on the same generatrix is less than 5 times the length of the larger defect, it shall be treated as a continuous defect: f) Visible defects with a length greater than 3mm and dense areas composed of non-metallic inclusions are not allowed; g) For defects that do not meet the requirements of 4.5.4, local grinding and polishing of the defects are allowed with the consent of the purchaser, but the depth of grinding and polishing should not exceed 1.6mm, and it should have a smooth transition with the surrounding surface. 4.6 Thermal stability test
The thermal stability test can be done by the purchaser, but the supplier shall be responsible for the test results. 4.7 Metallographic inspection
4.7.1 Average grain size of forgings: 30Cr1Mo1V steel should not be coarser than grade 2.0, and other steel types should not be coarser than grade 3.0. 4.7.2 The four types of inclusions A, B, C, and D of forgings should not exceed grade 3.0. 4.8 Residual stress
The residual stress of forgings should be measured, and its value should not be greater than 8% of the lower limit of radial compressive strength in Table 3. If the residual stress exceeds the above provisions, the forgings should still be supplemented with stress relief tempering in accordance with the provisions of 4.1.3.3, and the residual stress and hardness value should be re-measured. 4.9 Size and surface roughness | |tt||4.9.1 The processed forgings shall meet the requirements of size, tolerance and surface roughness specified in the order drawing. 4.9.2 If the order drawing does not specify, the straightness tolerance of the center hole axis is $3mm: the roundness tolerance of the center hole is 0.3mm, and the coaxiality tolerance of the center hole and the outer ring of the forging is 1.0mm.
5 Inspection rules and test methods
5.1 Chemical composition analysis
5.1.1 Chemical composition analysis shall be carried out in accordance with the methods specified in GB/T223.3~78 or other methods that can ensure the quality of analysis. 5.1.2 Each furnace (each package) of molten steel can be sampled during pouring to determine the chemical composition of the molten steel: when multiple furnaces are poured together, the weighted average analysis results shall also be reported. When smelting analysis is not possible, finished product analysis is allowed to replace smelting analysis. When sampling is taken from forgings, the analysis results shall meet the requirements of finished product analysis.
5.1.3 The finished product analysis specimen can be taken from the extended part of the forging at 1/3 of the surface, or from the radial performance acceptance test. 5.2 Mechanical performance inspection
5.2.1 Tensile performance inspection
Perform according to the methods specified in GB/T228 and ASTMA370. 5.2.2 Impact test
Perform according to the methods specified in GB/T229
5.2.3 High temperature endurance strength test
Perform according to GB/T2039, using No. 6 specimen of ASTME292. The test can be carried out at the purchaser, but the supplier shall ensure that the test results meet the requirements of Table 4.
5.2.4 Sampling for mechanical performance inspection
5.2.4.1 The specimens used for mechanical performance inspection shall be cut after performance heat treatment and before stress relief treatment. 5.2.4.2 Longitudinal specimens: Take one tensile specimen and three impact specimens at each end of the forging. The sampling position is 1/3 away from the surface. 5.2.4.3 Radial specimens: For rotors with a weight less than or equal to 6t after rough machining, take one tensile specimen and three impact specimens on the impeller body near the motor end; for rotors weighing more than 6t, take one tensile specimen and three impact specimens on the impeller body at both ends of the rotor body at 180° intervals (a total of four tensile specimens and 12 impact specimens), and take a group of FATTso specimens as required. FATTs can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. JB/T12652002
5.2.4.4 Center hole specimens: For forgings with a center hole greater than Φ90mm, take one tensile specimen, three impact specimens and a group of FATTso specimens from the center hole bar in the middle of the shaft body, and take one tensile specimen and three impact specimens from the shaft body near the motor end. FATTso can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. 5.3 Hardness test
One point shall be measured every 90° on the outer surface of the two journals and the shaft of each forging (a total of 12 points). The hardness test shall be carried out in accordance with the method specified in GB/T231.
5.4 Nondestructive testing
5.4.1 The magnetic particle test of the outer surface shall be carried out in accordance with JB/T8468, and the ultrasonic test of the outer surface shall be carried out in accordance with JB/T1581. 5.4.2 The ultrasonic test shall be carried out at least twice, the first test shall be carried out before quenching and tempering (before the center hole is punched for forgings with holes), and the second test shall be carried out after quenching and tempering (before the center hole is punched for forgings with holes). The results of both tests shall be provided to the buyer. If the buyer deems it necessary, the center hole ultrasonic test may be carried out. The center hole ultrasonic test shall be carried out in accordance with the method agreed upon by both parties. The supplier shall ensure that the center hole ultrasonic test results meet the provisions of the relevant provisions of this standard. 5.4.3 The center hole test shall be observed by a magic bore instrument, and if necessary, the center hole magnetic particle test shall be combined with the obstacle instrument for observation. 5.5 Metallographic inspection
5.5.1 Grain size inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and conduct according to the provisions of YB/T5148. 5.5.2 Inclusion inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and evaluate according to the rating diagram I in Appendix A of GB10561. 5.6 Determination of residual stress
5.6.1 The residual stress is determined by the ring cutting method or the ring core resistance strain method. 5.6.2 The ring cutting method is to cut a 25mmx25mm ring at one end of the shaft, and calculate the residual stress by measuring the average deformation of the ring before and after cutting. The calculation formula is:
0=E6/D
Where:
\-residual stress, unit is MPa:
E--elastic modulus of the material, unit is MPa. 8 Algebraic value of diameter increment, in mm
D---outer diameter of the ring before cutting, in mm: 5.6.3 When the residual stress is determined by the ring core resistance strain method, it shall be carried out in accordance with the provisions of JB/T8888. 5.7 Thermal stability test
The thermal stability test shall be carried out in accordance with the provisions of JB/T9021. 5.8 Retest
5.8.1 If a test result in the tensile test is unqualified, two specimens can be taken from the forging adjacent to the original specimen for retest, and the retest results of the two specimens shall meet the specified requirements. 5.8.2 In the impact test, if the average value of a group of three impact specimens is not lower than the specified requirements, and one of the values is not lower than 70% of the specified requirements, no retest is required: When the above requirements are not met, another group of three impact specimens shall be taken from the adjacent parts of the same product for retest, and the average value of the six specimens in the two groups before and after shall not be lower than the specified requirements, and there shall be no more than two single values lower than the specified value, and only one single value can be lower than 70% of the specified value.
5.8.3 If the mechanical property test fails due to white spots and cracks, retesting is not allowed. 5.9 Re-tempering
5.9.1 If the re-test result of any mechanical property of the forging is still unqualified, when the strength of the specimen is high but the plasticity, toughness or FATT does not meet the requirements, it is necessary to re-temper. For forgings with holes, the center hole specimen should be re-inserted into the hole and re-tempered together with the forging. After tempering, it should be inspected according to the provisions of 5.2. The sampling position of the center hole specimen of the forging with holes after re-tempering should be agreed upon with the purchaser. 5.9.2 If the mechanical property test results show that the forging cannot be re-tempered, the further heat treatment and processing of the forging must be agreed upon by the supply and demand parties.6um, the center hole inspection is carried out, and the acceptance criteria are as follows:
The axial and circumferential positions of defects equal to or greater than 1.5mm should be recorded and reported to the purchaser: a)
JB/T1265—2002
b) Within the range of 60cm\, three visible defects with a length greater than 1.5mm or nine visible defects with a length less than 1.5mm are not allowed:
c) The total length of all defects on the same generatrix on the inner hole surface should not be greater than 50mm: d) No tear-like bifurcation defects are allowed: e) When the distance between two defects on the same generatrix is less than 5 times the length of the larger defect, it shall be treated as a continuous defect: f) Visible defects with a length greater than 3mm and dense areas composed of non-metallic inclusions are not allowed; g) For defects that do not meet the requirements of 4.5.4, local grinding and polishing of the defects are allowed with the consent of the purchaser, but the depth of grinding and polishing should not exceed 1.6mm, and it should have a smooth transition with the surrounding surface. 4.6 Thermal stability test
The thermal stability test can be done by the purchaser, but the supplier shall be responsible for the test results. 4.7 Metallographic inspection
4.7.1 Average grain size of forgings: 30Cr1Mo1V steel should not be coarser than grade 2.0, and other steel types should not be coarser than grade 3.0. 4.7.2 The four types of inclusions A, B, C, and D of forgings should not exceed grade 3.0. 4.8 Residual stress
The residual stress of forgings should be measured, and its value should not be greater than 8% of the lower limit of radial compressive strength in Table 3. If the residual stress exceeds the above provisions, the forgings should still be supplemented with stress relief tempering in accordance with the provisions of 4.1.3.3, and the residual stress and hardness value should be re-measured. 4.9 Size and surface roughness | |tt||4.9.1 The processed forgings shall meet the requirements of size, tolerance and surface roughness specified in the order drawing. 4.9.2 If the order drawing does not specify, the straightness tolerance of the center hole axis is $3mm: the roundness tolerance of the center hole is 0.3mm, and the coaxiality tolerance of the center hole and the outer ring of the forging is 1.0mm.
5 Inspection rules and test methods
5.1 Chemical composition analysis
5.1.1 Chemical composition analysis shall be carried out in accordance with the methods specified in GB/T223.3~78 or other methods that can ensure the quality of analysis. 5.1.2 Each furnace (each package) of molten steel can be sampled during pouring to determine the chemical composition of the molten steel: when multiple furnaces are poured together, the weighted average analysis results shall also be reported. When smelting analysis is not possible, finished product analysis is allowed to replace smelting analysis. When sampling is taken from forgings, the analysis results shall meet the requirements of finished product analysis.
5.1.3 The finished product analysis specimen can be taken from the extended part of the forging at 1/3 of the surface, or from the radial performance acceptance test. 5.2 Mechanical performance inspection
5.2.1 Tensile performance inspection
Perform according to the methods specified in GB/T228 and ASTMA370. 5.2.2 Impact test
Perform according to the methods specified in GB/T229
5.2.3 High temperature endurance strength test
Perform according to GB/T2039, using No. 6 specimen of ASTME292. The test can be carried out at the purchaser, but the supplier shall ensure that the test results meet the requirements of Table 4.
5.2.4 Sampling for mechanical performance inspection
5.2.4.1 The specimens used for mechanical performance inspection shall be cut after performance heat treatment and before stress relief treatment. 5.2.4.2 Longitudinal specimens: Take one tensile specimen and three impact specimens at each end of the forging. The sampling position is 1/3 away from the surface. 5.2.4.3 Radial specimens: For rotors with a weight less than or equal to 6t after rough machining, take one tensile specimen and three impact specimens on the impeller body near the motor end; for rotors weighing more than 6t, take one tensile specimen and three impact specimens on the impeller body at both ends of the rotor body at 180° intervals (a total of four tensile specimens and 12 impact specimens), and take a group of FATTso specimens as required. FATTs can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. JB/T12652002
5.2.4.4 Center hole specimens: For forgings with a center hole greater than Φ90mm, take one tensile specimen, three impact specimens and a group of FATTso specimens from the center hole bar in the middle of the shaft body, and take one tensile specimen and three impact specimens from the shaft body near the motor end. FATTso can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. 5.3 Hardness test
One point shall be measured every 90° on the outer surface of the two journals and the shaft of each forging (a total of 12 points). The hardness test shall be carried out in accordance with the method specified in GB/T231.
5.4 Nondestructive testing
5.4.1 The magnetic particle test of the outer surface shall be carried out in accordance with JB/T8468, and the ultrasonic test of the outer surface shall be carried out in accordance with JB/T1581. 5.4.2 The ultrasonic test shall be carried out at least twice, the first test shall be carried out before quenching and tempering (before the center hole is punched for forgings with holes), and the second test shall be carried out after quenching and tempering (before the center hole is punched for forgings with holes). The results of both tests shall be provided to the buyer. If the buyer deems it necessary, the center hole ultrasonic test may be carried out. The center hole ultrasonic test shall be carried out in accordance with the method agreed upon by both parties. The supplier shall ensure that the center hole ultrasonic test results meet the provisions of the relevant provisions of this standard. 5.4.3 The center hole test shall be observed by a magic bore instrument, and if necessary, the center hole magnetic particle test shall be combined with the obstacle instrument for observation. 5.5 Metallographic inspection
5.5.1 Grain size inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and conduct according to the provisions of YB/T5148. 5.5.2 Inclusion inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and evaluate according to the rating diagram I in Appendix A of GB10561. 5.6 Determination of residual stress
5.6.1 The residual stress is determined by the ring cutting method or the ring core resistance strain method. 5.6.2 The ring cutting method is to cut a 25mmx25mm ring at one end of the shaft, and calculate the residual stress by measuring the average deformation of the ring before and after cutting. The calculation formula is:
0=E6/D
Where:
\-residual stress, unit is MPa:
E--elastic modulus of the material, unit is MPa. 8 Algebraic value of diameter increment, in mm
D---outer diameter of the ring before cutting, in mm: 5.6.3 When the residual stress is determined by the ring core resistance strain method, it shall be carried out in accordance with the provisions of JB/T8888. 5.7 Thermal stability test
The thermal stability test shall be carried out in accordance with the provisions of JB/T9021. 5.8 Retest
5.8.1 If a test result in the tensile test is unqualified, two specimens can be taken from the forging adjacent to the original specimen for retest, and the retest results of the two specimens shall meet the specified requirements. 5.8.2 In the impact test, if the average value of a group of three impact specimens is not lower than the specified requirements, and one of the values is not lower than 70% of the specified requirements, no retest is required: When the above requirements are not met, another group of three impact specimens shall be taken from the adjacent parts of the same product for retest, and the average value of the six specimens in the two groups before and after shall not be lower than the specified requirements, and there shall be no more than two single values lower than the specified value, and only one single value can be lower than 70% of the specified value.
5.8.3 If the mechanical property test fails due to white spots and cracks, retesting is not allowed. 5.9 Re-tempering
5.9.1 If the re-test result of any mechanical property of the forging is still unqualified, when the strength of the specimen is high but the plasticity, toughness or FATT does not meet the requirements, it is necessary to re-temper. For forgings with holes, the center hole specimen should be re-inserted into the hole and re-tempered together with the forging. After tempering, it should be inspected according to the provisions of 5.2. The sampling position of the center hole specimen of the forging with holes after re-tempering should be agreed upon with the purchaser. 5.9.2 If the mechanical property test results show that the forging cannot be re-tempered, the further heat treatment and processing of the forging must be agreed upon by the supply and demand parties.7 Metallographic inspection
4.7.1 Average grain size of forgings: 30Cr1Mo1V steel should not be coarser than grade 2.0, and other steel types should not be coarser than grade 3.0. 4.7.2 The four types of inclusions A, B, C, and D of forgings should not exceed grade 3.0. 4.8 Residual stress
The residual stress of forgings should be measured, and its value should not be greater than 8% of the lower limit of radial compressive strength in Table 3. If the residual stress exceeds the above provisions, the forgings should still be supplemented with stress relief tempering in accordance with the provisions of 4.1.3.3, and the residual stress and hardness value should be re-measured. 4.9 Dimensions and surface roughness
4.9.1 The processed forgings should meet the requirements of the order. 4.9.2 If the order drawing does not specify, the center hole axis straightness tolerance is $3mm: center hole roundness tolerance is 0.3mm, center hole and forging outer ring coaxiality tolerance is 1.0mm
5 Inspection rules and test methods
5.1 Chemical composition analysis
5.1.1 Chemical composition analysis shall be carried out in accordance with the methods specified in GB/T223.3~78 or other methods that can ensure the quality of analysis. 5.1.2 Each furnace (each package) of molten steel can be sampled during pouring to determine the chemical composition of the molten steel: when multiple furnaces are poured together, the weighted average analysis results shall also be reported. When smelting analysis is not possible, finished product analysis is allowed to replace smelting analysis. When sampling is taken from forgings, the analysis results shall meet the requirements of finished product analysis.
5.1.3 The finished product analysis specimen can be taken from the extended part of the forging at 1/3 of the surface, or from the radial performance acceptance test. 5.2 Mechanical performance inspection
5.2.1 Tensile performance inspection
Perform according to the methods specified in GB/T228 and ASTMA370. 5.2.2 Impact test
Perform according to the methods specified in GB/T229
5.2.3 High temperature endurance strength test
Perform according to GB/T2039, using No. 6 specimen of ASTME292. The test can be carried out at the purchaser, but the supplier shall ensure that the test results meet the requirements of Table 4.
5.2.4 Sampling for mechanical performance inspection
5.2.4.1 The specimens used for mechanical performance inspection shall be cut after performance heat treatment and before stress relief treatment. 5.2.4.2 Longitudinal specimens: Take one tensile specimen and three impact specimens at each end of the forging. The sampling position is 1/3 away from the surface. 5.2.4.3 Radial specimens: For rotors with a weight less than or equal to 6t after rough machining, take one tensile specimen and three impact specimens on the impeller body near the motor end; for rotors weighing more than 6t, take one tensile specimen and three impact specimens on the impeller body at both ends of the rotor body at 180° intervals (a total of four tensile specimens and 12 impact specimens), and take a group of FATTso specimens as required. FATTs can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. JB/T12652002
5.2.4.4 Center hole specimens: For forgings with a center hole greater than Φ90mm, take one tensile specimen, three impact specimens and a group of FATTso specimens from the center hole bar in the middle of the shaft body, and take one tensile specimen and three impact specimens from the shaft body near the motor end. FATTso can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. 5.3 Hardness test
One point shall be measured every 90° on the outer surface of the two journals and the shaft of each forging (a total of 12 points). The hardness test shall be carried out in accordance with the method specified in GB/T231.
5.4 Nondestructive testing
5.4.1 The magnetic particle test of the outer surface shall be carried out in accordance with JB/T8468, and the ultrasonic test of the outer surface shall be carried out in accordance with JB/T1581. 5.4.2 The ultrasonic test shall be carried out at least twice, the first test shall be carried out before quenching and tempering (before the center hole is punched for forgings with holes), and the second test shall be carried out after quenching and tempering (before the center hole is punched for forgings with holes). The results of both tests shall be provided to the buyer. If the buyer deems it necessary, the center hole ultrasonic test may be carried out. The center hole ultrasonic test shall be carried out in accordance with the method agreed upon by both parties. The supplier shall ensure that the center hole ultrasonic test results meet the requirements of the relevant provisions of this standard. 5.4.3 The center hole test shall be observed by a magic bore instrument, and if necessary, the center hole magnetic particle test shall be combined with a barrier instrument for observation. 5.5 Metallographic inspection
5.5.1 Grain size inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and conduct according to the provisions of YB/T5148. 5.5.2 Inclusion inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and evaluate according to the rating diagram I in Appendix A of GB10561. 5.6 Determination of residual stress
5.6.1 The residual stress is determined by the ring cutting method or the ring core resistance strain method. 5.6.2 The ring cutting method is to cut a 25mmx25mm ring at one end of the shaft, and calculate the residual stress by measuring the average deformation of the ring before and after cutting. The calculation formula is:
0=E6/D
Where:
\-residual stress, unit is MPa:
E--elastic modulus of the material, unit is MPa. 8 Algebraic value of diameter increment, in mm
D---outer diameter of the ring before cutting, in mm: 5.6.3 When the residual stress is determined by the ring core resistance strain method, it shall be carried out in accordance with the provisions of JB/T8888. 5.7 Thermal stability test
The thermal stability test shall be carried out in accordance with the provisions of JB/T9021. 5.8 Retest
5.8.1 If a test result in the tensile test is unqualified, two specimens can be taken from the forging adjacent to the original specimen for retest, and the retest results of the two specimens shall meet the specified requirements. 5.8.2 In the impact test, if the average value of a group of three impact specimens is not lower than the specified requirements, and one of the values is not lower than 70% of the specified requirements, no retest is required: When the above requirements are not met, another group of three impact specimens shall be taken from the adjacent parts of the same product for retest, and the average value of the six specimens in the two groups before and after shall not be lower than the specified requirements, and there shall be no more than two single values lower than the specified value, and only one single value can be lower than 70% of the specified value.
5.8.3 If the mechanical property test fails due to white spots and cracks, retesting is not allowed. 5.9 Re-tempering
5.9.1 If the re-test result of any mechanical property of the forging is still unqualified, when the strength of the specimen is high but the plasticity, toughness or FATT does not meet the requirements, it is necessary to re-temper. For forgings with holes, the center hole specimen should be re-inserted into the hole and re-tempered together with the forging. After tempering, it should be inspected according to the provisions of 5.2. The sampling position of the center hole specimen of the forging with holes after re-tempering should be agreed upon with the purchaser. 5.9.2 If the mechanical property test results show that the forging cannot be re-tempered, the further heat treatment and processing of the forging must be agreed upon by the supply and demand parties.7 Metallographic inspection
4.7.1 Average grain size of forgings: 30Cr1Mo1V steel should not be coarser than grade 2.0, other steel types should not be coarser than grade 3.0. 4.7.2 The four types of inclusions A, B, C and D of forgings should not exceed grade 3.0. 4.8 Residual stress
The residual stress of forgings should be measured, and its value should not be greater than 8% of the lower limit of radial compressive strength in Table 3. If the residual stress exceeds the above provisions, the forgings should still be supplemented with stress relief tempering in accordance with the provisions of 4.1.3.3, and the residual stress and hardness value should be re-measured. 4.9 Dimensions and surface roughness
4.9.1 The processed forgings should meet the requirements of the order. 4.9.2 If the order drawing does not specify, the center hole axis straightness tolerance is $3mm: center hole roundness tolerance is 0.3mm, center hole and forging outer ring coaxiality tolerance is 1.0mm
5 Inspection rules and test methods
5.1 Chemical composition analysis
5.1.1 Chemical composition analysis shall be carried out in accordance with the methods specified in GB/T223.3~78 or other methods that can ensure the quality of analysis. 5.1.2 Each furnace (each package) of molten steel can be sampled during pouring to determine the chemical composition of the molten steel: when multiple furnaces are poured together, the weighted average analysis results shall also be reported. When smelting analysis is not possible, finished product analysis is allowed to replace smelting analysis. When sampling is taken from forgings, the analysis results shall meet the requirements of finished product analysis.
5.1.3 The finished product analysis specimen can be taken from the extended part of the forging at 1/3 of the surface, or from the radial performance acceptance test. 5.2 Mechanical performance inspection
5.2.1 Tensile performance inspection
Perform according to the methods specified in GB/T228 and ASTMA370. 5.2.2 Impact test
Perform according to the methods specified in GB/T229
5.2.3 High temperature endurance strength test
Perform according to GB/T2039, using No. 6 specimen of ASTME292. The test can be carried out at the purchaser, but the supplier shall ensure that the test results meet the requirements of Table 4.
5.2.4 Sampling for mechanical performance inspection
5.2.4.1 The specimens used for mechanical performance inspection shall be cut after performance heat treatment and before stress relief treatment. 5.2.4.2 Longitudinal specimens: Take one tensile specimen and three impact specimens at each end of the forging. The sampling position is 1/3 away from the surface. 5.2.4.3 Radial specimens: For rotors with a weight less than or equal to 6t after rough machining, take one tensile specimen and three impact specimens on the impeller body near the motor end; for rotors weighing more than 6t, take one tensile specimen and three impact specimens on the impeller body at both ends of the rotor body at 180° intervals (a total of four tensile specimens and 12 impact specimens), and take a group of FATTso specimens as required. FATTs can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. JB/T12652002
5.2.4.4 Center hole specimens: For forgings with a center hole greater than Φ90mm, take one tensile specimen, three impact specimens and a group of FATTso specimens from the center hole bar in the middle of the shaft body, and take one tensile specimen and three impact specimens from the shaft body near the motor end. FATTso can take three specimens and test them at the specified temperature. All three specimens should show at least 50% fibrous fracture. 5.3 Hardness test
One point shall be measured every 90° on the outer surface of the two journals and the shaft of each forging (a total of 12 points). The hardness test shall be carried out in accordance with the method specified in GB/T231.
5.4 Nondestructive testing
5.4.1 The magnetic particle test of the outer surface shall be carried out in accordance with JB/T8468, and the ultrasonic test of the outer surface shall be carried out in accordance with JB/T1581. 5.4.2 The ultrasonic test shall be carried out at least twice, the first test shall be carried out before quenching and tempering (before the center hole is punched for forgings with holes), and the second test shall be carried out after quenching and tempering (before the center hole is punched for forgings with holes). The results of both tests shall be provided to the buyer. If the buyer deems it necessary, the center hole ultrasonic test may be carried out. The center hole ultrasonic test shall be carried out in accordance with the method agreed upon by both parties. The supplier shall ensure that the center hole ultrasonic test results meet the provisions of the relevant provisions of this standard. 5.4.3 The center hole test shall be observed by a magic bore instrument, and if necessary, the center hole magnetic particle test shall be combined with the obstacle instrument for observation. 5.5 Metallographic inspection
5.5.1 Grain size inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and conduct according to the provisions of YB/T5148. 5.5.2 Inclusion inspection: Take samples from the motor end of the shaft and the middle of the center hole bar, and evaluate according to the rating diagram I in Appendix A of GB10561. 5.6 Determination of residual stress
5.6.1 The residual stress is determined by the ring cutting method or the ring core resistance strain method. 5.6.2 The ring cutting method is to cut a 25mmx25mm ring at one end of the shaft, and calculate the residual stress by measuring the average deformation of the ring before and after cutting. The calculation formula is:
0=E6/D
Where:
\-residual stress, unit is MPa:
E--elastic modulus of the material, unit is MPa. 8 Algebraic value of diameter increment, in mm
D---outer diameter of the ring before cutting, in mm: 5.6.3 When the residual stress is determined by the ring core resistance strain method, it shall be carried out in accordance with the provisions of JB/T8888. 5.7 Thermal stability test
The thermal stability test shall be carried out in accordance with the provisions of JB/T9021. 5.8 Retest
5.8.1 If a test result in the tensile test is unqualified, two specimens can be taken from the forging adjacent to the original specimen for retest, and the retest results of the two specimens shall meet the specified requirements. 5.8.2 In the impact test, if the average value of a group of three impact specimens is not lower than the specified requirements, and one of the values is not lower than 70% of the specified requirements, no retest is required: When the above requirements are not met, another group of three impact specimens shall be taken from the adjacent parts of the same product for retest, and the average value of the six specimens in the two groups before and after shall not be lower than the specified requirements, and there shall be no more than two single values lower than the specified value, and only one single value can be lower than 70% of the specified value.
5.8.3 If the mechanical property test fails due to white spots and cracks, retesting is not allowed. 5.9 Re-tempering
5.9.1 If the re-test result of any mechanical property of the forging is still unqualified, when the strength of the specimen is high but the plasticity, toughness or FATT does not meet the requirements, it is necessary to re-temper. For forgings with holes, the center hole specimen should be re-inserted into the hole and re-tempered together with the forging. After tempering, it should be inspected according to the provisions of 5.2. The sampling position of the center hole specimen of the forging with holes after re-tempering should be agreed upon with the purchaser. 5.9.2 If the mechanical property test results show that the forging cannot be re-tempered, the further heat treatment and processing of the forging must be agreed upon by the supply and demand parties.1 The specimens used for mechanical property inspection shall be cut after performance heat treatment and before stress relief treatment. 5.2.4.2 Longitudinal specimens: Take one tensile specimen and three impact specimens at each end of the forging. The sampling position is 1/3 away from the surface. 5.2.4.3 Radial specimens: For rotor bodies with a weight of less than or equal to 6t after rough machining, take one tensile specimen and three impact specimens on the impeller body close to the motor end; for rotor bodies weighing more than 6t, take one tensile specimen and three impact specimens at 180° intervals on the impeller bodies at both ends of the rotor body (a total of four tensile specimens and 12 impact specimens), and take a set of FATTso specimens as required. FATTs can take three specimens for testing at the specified temperature, and all three specimens should show at least 50% fibrous fracture. JB/T12652002
5.2.4.4 Center hole test specimen: For forgings with a center hole greater than Φ90mm, take a tensile test specimen, three impact test specimens and a set of FATTso test specimens from the center hole bar in the middle of the shaft body, and take a tensile test specimen and three impact test specimens from the shaft body near the motor end. FATTso can take three test specimens and test them at the specified temperature. All three test specimens should show at least 50% fibrous fracture. 5.3 Hardness test
Measure one point every 90° on the outer surface of the two journals and the shaft body of each forging (a total of 12 points). The hardness test is carried out in accordance with the method specified in GB/T231.
5.4 Non-destructive testing
5.4.1 The magnetic particle test of the outer surface is carried out in accordance with JB/T8468, and the ultrasonic test of the outer surface is carried out in accordance with JB/T1581
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.